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Campbell JS, Pearce JC, Bebes A, Pradhan A, Yuecel R, Brown AJP, Wakefield JG. Characterising phagocytes and measuring phagocytosis from live Galleria mellonella larvae. Virulence 2024; 15:2313413. [PMID: 38357909 PMCID: PMC10877982 DOI: 10.1080/21505594.2024.2313413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/29/2024] [Indexed: 02/16/2024] Open
Abstract
Over the last 20 years, the larva of the greater waxmoth, Galleria mellonella, has rapidly increased in popularity as an in vivo mammalian replacement model organism for the study of human pathogens. Experimental readouts of response to infection are most often limited to observing the melanization cascade and quantifying larval death and, whilst transcriptomic and proteomic approaches, and methods to determine microbial load are also used, a more comprehensive toolkit of profiling infection over time could transform the applicability of this model. As an invertebrate, Galleria harbour an innate immune system comprised of both humoral components and a repertoire of innate immune cells - termed haemocytes. Although information on subtypes of haemocytes exists, there are conflicting reports on their exact number and function. Flow cytometry has previously been used to assay Galleria haemocytes, but protocols include both centrifugation and fixation - physical methods which have the potential to affect haemocyte morphology prior to analysis. Here, we present a method for live haemocyte analysis by flow cytometry, revealing that Galleria haemocytes constitute only a single resolvable population, based on relative size or internal complexity. Using fluorescent zymosan particles, we extend our method to show that up to 80% of the Galleria haemocyte population display phagocytic capability. Finally, we demonstrate that the developed assay reliably replicates in vitro data, showing that cell wall β-1,3-glucan masking by Candida albicans subverts phagocytic responses. As such, our method provides a new tool with which to rapidly assess phagocytosis and understand live infection dynamics in Galleria.
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Affiliation(s)
| | | | - Attila Bebes
- Exeter Centre for Cytomics, Henry Wellcome Building for Biocatalysis, Biosciences, University of Exeter, Exeter, UK
| | - Arnab Pradhan
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Raif Yuecel
- Exeter Centre for Cytomics, Henry Wellcome Building for Biocatalysis, Biosciences, University of Exeter, Exeter, UK
| | - Alistair J P Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
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Sahu SR, Dutta A, Peroumal D, Kumari P, Utakalaja BG, Patel SK, Acharya N. Immunogenicity and efficacy of CNA25 as a potential whole-cell vaccine against systemic candidiasis. EMBO Mol Med 2024:10.1038/s44321-024-00080-8. [PMID: 38783167 DOI: 10.1038/s44321-024-00080-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
Disseminated fungal infections account for ~1.5 million deaths per year worldwide, and mortality may increase further due to a rise in the number of immunocompromised individuals and drug-resistance fungal species. Since an approved antifungal vaccine is yet to be available, this study explored the immunogenicity and vaccine efficacy of a DNA polymerase mutant strain of Candida albicans. CNA25 is a pol32ΔΔ strain that exhibits growth defects and does not cause systemic candidiasis in mice. Immunized mice with live CNA25 were fully protected against C. albicans and C. parapsilosis but partially against C. tropicalis and C. glabrata infections. CNA25 induced steady expression of TLR2 and Dectin-1 receptors leading to a faster recognition and clearance by the immune system associated with the activation of protective immune responses mostly mediated by neutrophils, macrophages, NK cells, B cells, and CD4+ and CD8+ T cells. Molecular blockade of Dectin-1, IL-17, IFNγ, and TNFα abolished resistance to reinfection. Altogether, this study suggested that CNA25 collectively activates innate, adaptive, and trained immunity to be a promising live whole-cell vaccine against systemic candidiasis.
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Affiliation(s)
- Satya Ranjan Sahu
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
- Regional Center for Biotechnology, Faridabad, Haryana, 751021, India
| | - Abinash Dutta
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
| | - Doureradjou Peroumal
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
| | - Premlata Kumari
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
- Regional Center for Biotechnology, Faridabad, Haryana, 751021, India
| | - Bhabasha Gyanadeep Utakalaja
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
- Regional Center for Biotechnology, Faridabad, Haryana, 751021, India
| | - Shraddheya Kumar Patel
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India
- Regional Center for Biotechnology, Faridabad, Haryana, 751021, India
| | - Narottam Acharya
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, 751023, India.
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McCrory C, Lenardon M, Traven A. Bacteria-derived short-chain fatty acids as potential regulators of fungal commensalism and pathogenesis. Trends Microbiol 2024:S0966-842X(24)00089-1. [PMID: 38729839 DOI: 10.1016/j.tim.2024.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/08/2024] [Accepted: 04/16/2024] [Indexed: 05/12/2024]
Abstract
The human gastrointestinal microbiome encompasses bacteria, fungi, and viruses forming complex bionetworks which, for organismal health, must be in a state of homeostasis. An important homeostatic mechanism derives from microbial competition, which maintains the relative abundance of microbial species in a healthy balance. Microbes compete for nutrients and secrete metabolites that inhibit other microbes. Short-chain fatty acids (SCFAs) are one such class of metabolites made by gut bacteria to very high levels. SCFAs are metabolised by microbes and host cells and have multiple roles in regulating cell physiology. Here, we review the mechanisms by which SCFAs regulate the fungal gut commensal Candida albicans. We discuss SCFA's ability to inhibit fungal growth, limit invasive behaviours and modulate cell surface antigens recognised by immune cells. We review the mechanisms underlying these roles: regulation of gene expression, metabolism, signalling and SCFA-driven post-translational protein modifications by acylation, which contribute to changes in acylome dynamics of C. albicans with potentially large consequences for cell physiology. Given that the gut mycobiome is a reservoir for systemic disease and has also been implicated in inflammatory bowel disease, understanding the mechanisms by which bacterial metabolites, such as SCFAs, control the mycobiome might provide therapeutic avenues.
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Affiliation(s)
- Christopher McCrory
- Department of Biochemistry and Molecular Biology, Infection Program, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia; Centre to Impact AMR, Monash University, Clayton 3800, Victoria, Australia
| | - Megan Lenardon
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Ana Traven
- Department of Biochemistry and Molecular Biology, Infection Program, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia; Centre to Impact AMR, Monash University, Clayton 3800, Victoria, Australia.
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Yang C, Li G, Zhang Q, Bai W, Li Q, Zhang P, Zhang J. Histone deacetylase Sir2 promotes the systemic Candida albicans infection by facilitating its immune escape via remodeling the cell wall and maintaining the metabolic activity. mBio 2024:e0044524. [PMID: 38682948 DOI: 10.1128/mbio.00445-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 03/26/2024] [Indexed: 05/01/2024] Open
Abstract
Histone deacetylation affects Candida albicans (C. albicans) pathogenicity by modulating virulence factor expression and DNA damage. The histone deacetylase Sir2 is associated with C. albicans plasticity and maintains genome stability to help C. albicans adapt to various environmental niches. However, whether Sir2-mediated chromatin modification affects C. albicans virulence is unclear. The purpose of our study was to investigate the effect of Sir2 on C. albicans pathogenicity and regulation. Here, we report that Sir2 is required for C. albicans pathogenicity, as its deletion affects the survival rate, fungal burden in different organs and the extent of tissue damage in a mouse model of disseminated candidiasis. We evaluated the impact of Sir2 on C. albicans virulence factors and revealed that the Sir2 null mutant had an impaired ability to adhere to host cells and was more easily recognized by the innate immune system. Comprehensive analysis revealed that the disruption of C. albicans adhesion was due to a decrease in cell surface hydrophobicity rather than the differential expression of adhesion genes on the cell wall. In addition, Sir2 affects the distribution and exposure of mannan and β-glucan on the cell wall, indicating that Sir2 plays a role in preventing the immune system from recognizing C. albicans. Interestingly, our results also indicated that Sir2 helps C. albicans maintain metabolic activity under hypoxic conditions, suggesting that Sir2 contributes to C. albicans colonization at hypoxic sites. In conclusion, our findings provide detailed insights into antifungal targets and a useful foundation for the development of antifungal drugs. IMPORTANCE Candida albicans (C. albicans) is the most common opportunistic fungal pathogen and can cause various superficial infections and even life-threatening systemic infections. To successfully propagate infection, this organism relies on the ability to express virulence-associated factors and escape host immunity. In this study, we demonstrated that the histone deacetylase Sir2 helps C. albicans adhere to host cells and escape host immunity by mediating cell wall remodeling; as a result, C. albicans successfully colonized and invaded the host in vivo. In addition, we found that Sir2 contributes to carbon utilization under hypoxic conditions, suggesting that Sir2 is important for C. albicans survival and the establishment of infection in hypoxic environments. In summary, we investigated the role of Sir2 in regulating C. albicans pathogenicity in detail; these findings provide a potential target for the development of antifungal drugs.
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Affiliation(s)
- Chen Yang
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Guanglin Li
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Qiyue Zhang
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Wenhui Bai
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Qingiqng Li
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Peipei Zhang
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Jiye Zhang
- School of Pharmacy, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Pharmaceutical Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China
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Kuo CY, Tay RJ, Lin HC, Juan SC, Vidal-Diez de Ulzurrun G, Chang YC, Hoki J, Schroeder FC, Hsueh YP. The nematode-trapping fungus Arthrobotrys oligospora detects prey pheromones via G protein-coupled receptors. Nat Microbiol 2024:10.1038/s41564-024-01679-w. [PMID: 38649409 DOI: 10.1038/s41564-024-01679-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 03/20/2024] [Indexed: 04/25/2024]
Abstract
The ability to sense prey-derived cues is essential for predatory lifestyles. Under low-nutrient conditions, Arthrobotrys oligospora and other nematode-trapping fungi develop dedicated structures for nematode capture when exposed to nematode-derived cues, including a conserved family of pheromones, the ascarosides. A. oligospora senses ascarosides via conserved MAPK and cAMP-PKA pathways; however, the upstream receptors remain unknown. Here, using genomic, transcriptomic and functional analyses, we identified two families of G protein-coupled receptors (GPCRs) involved in sensing distinct nematode-derived cues. GPCRs homologous to yeast glucose receptors are required for ascaroside sensing, whereas Pth11-like GPCRs contribute to ascaroside-independent nematode sensing. Both GPCR classes activate conserved cAMP-PKA signalling to trigger trap development. This work demonstrates that predatory fungi use multiple GPCRs to sense several distinct nematode-derived cues for prey recognition and to enable a switch to a predatory lifestyle. Identification of these receptors reveals the molecular mechanisms of cross-kingdom communication via conserved pheromones also sensed by plants and animals.
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Affiliation(s)
- Chih-Yen Kuo
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Rebecca J Tay
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Hung-Che Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Sheng-Chian Juan
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Yu-Chu Chang
- Department of Biochemistry and Molecular Cell Biology, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Jason Hoki
- Boyce Thompson Institute, Cornell University, Ithaca, NY, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Frank C Schroeder
- Boyce Thompson Institute, Cornell University, Ithaca, NY, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Yen-Ping Hsueh
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan.
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
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6
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Jin P, Wang L, Chen D, Chen Y. Unveiling the complexity of early childhood caries: Candida albicans and Streptococcus mutans cooperative strategies in carbohydrate metabolism and virulence. J Oral Microbiol 2024; 16:2339161. [PMID: 38606339 PMCID: PMC11008315 DOI: 10.1080/20002297.2024.2339161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 04/01/2024] [Indexed: 04/13/2024] Open
Abstract
Objective To explore the mechanisms underlying the virulence changes in early childhood caries (ECC) caused by Candida albicans (C. albicans) and Streptococcus mutans (S. mutans), with a focus on carbohydrate metabolism and environmental acidification. Methods A review of literature was conducted to understand the symbiotic relationship between C. albicans and S. mutans, and their role in the pathogenesis of ECC. The review also examined how their interactions influence carbohydrate metabolism and environmental acidification in the oral cavity. Results C. albicans and S. mutans play crucial roles in the onset and progression of ECC. C. albicans promotes the adhesion and accumulation of S. mutans, while S. mutans creates an environment favorable for the growth of C. albicans. Their interactions, especially through carbohydrate metabolism, strengthen their pathogenic potential. The review highlights the importance of understanding these mechanisms for the development of effective management and treatment protocols for ECC. Conclusion The symbiotic relationship between C. albicans and S. mutans, and their interactions through carbohydrate metabolism and environmental acidification, are key factors in the pathogenesis of ECC. A comprehensive understanding of these mechanisms is crucial for developing effective strategies to manage and treat ECC.
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Affiliation(s)
- Pingping Jin
- Wuxi Maternal and Child Health Hospital, Wuxi School of Medicine, Jiangnan University, Jiangsu, China
| | - Lu Wang
- Wuxi Maternal and Child Health Hospital, Wuxi School of Medicine, Jiangnan University, Jiangsu, China
| | - Daozhen Chen
- Wuxi Maternal and Child Health Hospital, Wuxi School of Medicine, Jiangnan University, Jiangsu, China
| | - Yu Chen
- Wuxi Maternal and Child Health Hospital, Wuxi School of Medicine, Jiangnan University, Jiangsu, China
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Pedro NA, Mira NP. A molecular view on the interference established between vaginal Lactobacilli and pathogenic Candida species: Challenges and opportunities for the development of new therapies. Microbiol Res 2024; 281:127628. [PMID: 38246122 DOI: 10.1016/j.micres.2024.127628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/03/2024] [Accepted: 01/15/2024] [Indexed: 01/23/2024]
Abstract
Vaginal infectious diseases caused by viruses and bacteria have been linked to the occurrence of dysbiosis, that is, a reduction in the abundance of the normally dominating vaginal Lactobacillus species. Mucosal infections in the vagina and/or vulva caused by Candida species, usually known as vulvovaginal candidiasis (or VVC), are among the leading causes of diseases in the vaginal tract. The existence of a clear link between the occurrence of dysbiosis and the development of VVC is still unclear, although multiple observations point in that direction. Based on the idea that vaginal health is linked to a microbiota dominated by lactobacilli, several probiotics have been used in management of VVC, either alone or in combination with antifungals, having obtained different degrees of success. In most cases, the undertaken trials resorted to lactobacilli species other than those indigenous to the vaginal tract, although in vitro these vaginal species were shown to reduce growth, viability and virulence of Candida. In this paper we overview the role of lactobacilli and Candida in the vaginal micro- and myco-biomes, while discussing the results obtained in what concerns the establishment of interference mechanisms in vivo and the environmental factors that could determine that. We also overview the molecular mechanisms by which lactobacilli species have been shown to inhibit pathophysiology of Candida, including the description of the genes and pathways determining their ability to thrive in the presence of each other. In a time where concerns are increasing with the emergence of antifungal resistance and the slow pace of discovery of new antifungals, a thorough understanding of the molecular mechanisms underneath the anti-Candida effect prompted by vaginal lactobacilli is of utmost importance to assure a knowledge-based design of what can be a new generation of pharmaceuticals, eventually focusing therapeutic targets other than the usual ones.
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Affiliation(s)
- Nuno A Pedro
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico - Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Nuno P Mira
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico - Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
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Cohen S, Ost KS, Doran KS. Impact of interkingdom microbial interactions in the vaginal tract. PLoS Pathog 2024; 20:e1012018. [PMID: 38457371 PMCID: PMC10923463 DOI: 10.1371/journal.ppat.1012018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2024] Open
Affiliation(s)
- Shirli Cohen
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
| | - Kyla S. Ost
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
| | - Kelly S. Doran
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
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Devi KS, R A, Kizhakkoottu S. Clinico-Demographic Parameters of Oral Fungal Infections: An Institutional Retrospective Study. Cureus 2024; 16:e55386. [PMID: 38562320 PMCID: PMC10983061 DOI: 10.7759/cureus.55386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 03/02/2024] [Indexed: 04/04/2024] Open
Abstract
Introduction Most fungal infections are responsive to antifungal therapy. However, failure to diagnose the same can significantly affect the quality of lives of patients. Timely identification of fungal infections and their association with varied demographic and clinical parameters will help in improving the prognosis of the patient. The present study aims to evaluate the prevalence of fungal infections among various age groups and genders and also to evaluate the association of fungal infections with demographic parameters. Methods This study included a sample size of n = 600. The demographic and clinical details were compiled and transferred to IBM SPSS Version 23 software (IBM Corp., Armonk, NY) for statistical analysis. Descriptive and Pearson chi-square tests were used to analyze the association of the type of fungal infection with gender, age, and comorbidities. A p-value of less than 0.05 is considered statistically significant. Results Angular cheilitis (40%, 240), followed by denture stomatitis (37.5%, 225), were the most common type of fungal infection among the sample population, and the elderly age group (51-72 years) was the most affected. Angular cheilitis was the most common infection among both males (21.4%, 128) and females (18.6%, 112), but candidiasis was reported more in females (18%, 108) than males (3%, 18) (p = 0.00). Angular cheilitis (32%, 192) and candidiasis (18%, 108) were more observed in association with anemia; however, denture stomatitis (34%, 204) was significantly higher among diabetics (p = 0.00). Conclusion The identification of associated systemic and demographic factors is as important as the treatment of fungal infection itself. The recognition of fungal infections and the role of parameters like age, gender, and systemic comorbidities in the development of fungal infections will have valuable implications for public health. Future research is required for a clear understanding of the same.
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Affiliation(s)
- Kamala S Devi
- Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Abilasha R
- Oral Pathology and Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Suvarna Kizhakkoottu
- Oral Pathology and Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
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Ye F, Kang Z, Kou H, Yang Y, Chen W, Wang S, Sun J, Liu F. G-Protein Coupled Receptor Gpr-1 Is Important for the Growth and Nutritional Metabolism of an Invasive Bark Beetle Symbiont Fungi Leptographium procerum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:3354-3362. [PMID: 38230891 DOI: 10.1021/acs.jafc.3c07547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Leptographium procerum has been demonstrated to play important roles in the invasive success of red turpentine beetle (RTB), one of the most destructive invasive pests in China. Our previous studies found that bacterial volatile ammonia plays an important role in the maintenance of the RTB-L. procerum invasive complex. In this study, we found a GPCR gene Gpr-1 that was a response to ammonia but not involved in the ammonia-induced carbohydrate metabolism. Deletion of Gpr-1 significantly inhibited the growth and pathogenicity but thickened the cell wall of L. procerum, resulting in more resistance to cell wall-perturbing agents. Further analyses suggested that Gpr-1 deletion caused growth defects that might be due to the dysregulation of the amino acid and lipid metabolisms. The thicker cell wall in the ΔGpr-1 mutant was induced through the cell wall remodeling process. Our results indicated that Gpr-1 is essential for the growth of L. procerum by regulating the nutritional metabolism, which can be further explored for potential applications in the management of RTB.
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Affiliation(s)
- Fangyuan Ye
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiwei Kang
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Hongru Kou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunwen Yang
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Wei Chen
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Saige Wang
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Jianghua Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Fanghua Liu
- College of Life Science/Hebei Basic Science Center for Biotic Interactions, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
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Avelar GM, Pradhan A, Ma Q, Hickey E, Leaves I, Liddle C, Rodriguez Rondon AV, Kaune AK, Shaw S, Maufrais C, Sertour N, Bain JM, Larcombe DE, de Assis LJ, Netea MG, Munro CA, Childers DS, Erwig LP, Brown GD, Gow NAR, Bougnoux ME, d'Enfert C, Brown AJP. A CO 2 sensing module modulates β-1,3-glucan exposure in Candida albicans. mBio 2024; 15:e0189823. [PMID: 38259065 PMCID: PMC10865862 DOI: 10.1128/mbio.01898-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Microbial species capable of co-existing with healthy individuals, such as the commensal fungus Candida albicans, exploit multifarious strategies to evade our immune defenses. These strategies include the masking of immunoinflammatory pathogen-associated molecular patterns (PAMPs) at their cell surface. We reported previously that C. albicans actively reduces the exposure of the proinflammatory PAMP, β-1,3-glucan, at its cell surface in response to host-related signals such as lactate and hypoxia. Here, we show that clinical isolates of C. albicans display phenotypic variability with respect to their lactate- and hypoxia-induced β-1,3-glucan masking. We have exploited this variability to identify responsive and non-responsive clinical isolates. We then performed RNA sequencing on these isolates to reveal genes whose expression patterns suggested potential association with lactate- or hypoxia-induced β-1,3-glucan masking. The deletion of two such genes attenuated masking: PHO84 and NCE103. We examined NCE103-related signaling further because NCE103 has been shown previously to encode carbonic anhydrase, which promotes adenylyl cyclase-protein kinase A (PKA) signaling at low CO2 levels. We show that while CO2 does not trigger β-1,3-glucan masking in C. albicans, the Sch9-Rca1-Nce103 signaling module strongly influences β-1,3-glucan exposure in response to hypoxia and lactate. In addition to identifying a new regulatory module that controls PAMP exposure in C. albicans, our data imply that this module is important for PKA signaling in response to environmental inputs other than CO2.IMPORTANCEOur innate immune defenses have evolved to protect us against microbial infection in part via receptor-mediated detection of "pathogen-associated molecular patterns" (PAMPs) expressed by invading microbes, which then triggers their immune clearance. Despite this surveillance, many microbial species are able to colonize healthy, immune-competent individuals, without causing infection. To do so, these microbes must evade immunity. The commensal fungus Candida albicans exploits a variety of strategies to evade immunity, one of which involves reducing the exposure of a proinflammatory PAMP (β-1,3-glucan) at its cell surface. Most of the β-1,3-glucan is located in the inner layer of the C. albicans cell wall, hidden by an outer layer of mannan fibrils. Nevertheless, some β-1,3-glucan can become exposed at the fungal cell surface. However, in response to certain specific host signals, such as lactate or hypoxia, C. albicans activates an anticipatory protective response that decreases β-1,3-glucan exposure, thereby reducing the susceptibility of the fungus to impending innate immune attack. Here, we exploited the natural phenotypic variability of C. albicans clinical isolates to identify strains that do not display the response to β-1,3-glucan masking signals observed for the reference isolate, SC5314. Then, using genome-wide transcriptional profiling, we compared these non-responsive isolates with responsive controls to identify genes potentially involved in β-1,3-glucan masking. Mutational analysis of these genes revealed that a sensing module that was previously associated with CO2 sensing also modulates β-1,3-glucan exposure in response to hypoxia and lactate in this major fungal pathogen of humans.
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Affiliation(s)
- Gabriela M. Avelar
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Arnab Pradhan
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Qinxi Ma
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Emer Hickey
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Corin Liddle
- Bioimaging Unit, University of Exeter, Exeter, United Kingdom
| | - Alejandra V. Rodriguez Rondon
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Ann-Kristin Kaune
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Sophie Shaw
- Centre for Genome Enabled Biology and Medicine, University of Aberdeen, Aberdeen, United Kingdom
| | - Corinne Maufrais
- Institut Pasteur, Université Paris Cité, INRAe USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Natacha Sertour
- Institut Pasteur, Université Paris Cité, INRAe USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Judith M. Bain
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Daniel E. Larcombe
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Leandro J. de Assis
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Carol A. Munro
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Delma S. Childers
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Lars P. Erwig
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Johnson-Johnson Innovation, EMEA Innovation Centre, London, United Kingdom
| | - Gordon D. Brown
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Neil A. R. Gow
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Marie-Elisabeth Bougnoux
- Institut Pasteur, Université Paris Cité, INRAe USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
- Unité de Parasitologie-Mycologie, Service de Microbiologie Clinique, Hôpital Necker-Enfants-Malades, Assistance Publique des Hôpitaux de Paris (APHP), Paris, France
- Université Paris Cité, Paris, France
| | - Christophe d'Enfert
- Institut Pasteur, Université Paris Cité, INRAe USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Alistair J. P. Brown
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, United Kingdom
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12
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Kadakia P, Valentin JDP, Hong L, Watts S, Hameed OA, Walch M, Salentinig S. Biocompatible Rhamnolipid Self-Assemblies with pH-Responsive Antimicrobial Activity. Adv Healthc Mater 2024; 13:e2302596. [PMID: 37935580 DOI: 10.1002/adhm.202302596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/23/2023] [Indexed: 11/09/2023]
Abstract
There is an urgent need for alternative antimicrobial materials due to the growing challenge of bacteria becoming resistant to conventional antibiotics. This study demonstrates the creation of a biocompatible pH-switchable antimicrobial material by combining bacteria-derived rhamnolipids (RL) and food-grade glycerol monooleate (GMO). The integration of RL into dispersed GMO particles, with an inverse-type liquid crystalline cubic structure in the core, leads to colloidally stable supramolecular materials. The composition and pH-triggered structural transformations are studied with small-angle X-ray scattering, cryogenic transmission electron microscopy, and dynamic light scattering. The composition-structure-activity relationship is analyzed and optimized to target bacteria at acidic pH values of acute wounds. The new RL/GMO dispersions reduce Staphylococcus aureus (S. aureus) populations by 7-log after 24 h of treatment with 64 µg mL-1 of RL and prevent biofilm formation at pH = 5.0, but have no activity at pH = 7.0. Additionally, the system is active against methicillin-resistant S. aureus (MRSA) with minimum inhibitory concentration of 128 µg mL-1 at pH 5.0. No activity is found against several Gram-negative bacteria at pH 5.0 and 7.0. The results provide a fundamental understanding of lipid self-assembly and the design of lipid-based biomaterials, which can further guide the development of alternative bio-based solutions to combat bacteria.
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Affiliation(s)
- Parth Kadakia
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Jules D P Valentin
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Samuel Watts
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Owais Abdul Hameed
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, 1700, Switzerland
| | - Michael Walch
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, 1700, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
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13
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Lim SJ, Muhd Noor ND, Sabri S, Mohamad Ali MS, Salleh AB, Oslan SN. Bibliometric analysis and thematic review of Candida pathogenesis: Fundamental omics to applications as potential antifungal drugs and vaccines. Med Mycol 2024; 62:myad126. [PMID: 38061839 DOI: 10.1093/mmy/myad126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/21/2023] [Accepted: 12/06/2023] [Indexed: 01/11/2024] Open
Abstract
Invasive candidiasis caused by the pathogenic Candida yeast species has resulted in elevating global mortality. The pathogenicity of Candida spp. is not only originated from its primary invasive yeast-to-hyphal transition; virulence factors (transcription factors, adhesins, invasins, and enzymes), biofilm, antifungal drug resistance, stress tolerance, and metabolic adaptation have also contributed to a greater clinical burden. However, the current research theme in fungal pathogenicity could hardly be delineated with the increasing research output. Therefore, our study analysed the research trends in Candida pathogenesis over the past 37 years via a bibliometric approach against the Scopus and Web of Science databases. Based on the 3993 unique documents retrieved, significant international collaborations among researchers were observed, especially between Germany (Bernhard Hube) and the UK (Julian Naglik), whose focuses are on Candida proteinases, adhesins, and candidalysin. The prominent researchers (Neils Gow, Alistair Brown, and Frank Odds) at the University of Exeter and the University of Aberdeen (second top performing affiliation) UK contribute significantly to the mechanisms of Candida adaptation, tolerance, and stress response. However, the science mapping of co-citation analysis performed herein could not identify a hub representative of subsequent work since the clusters were semi-redundant. The co-word analysis that was otherwise adopted, revealed three research clusters; the cluster-based thematic analyses indicated the severeness of Candida biofilm and antifungal resistance as well as the elevating trend on molecular mechanism elucidation for drug screening and repurposing. Importantly, the in vivo pathogen adaptation and interactions with hosts are crucial for potential vaccine development.
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Affiliation(s)
- Si Jie Lim
- Enzyme Technology and X-ray Crystallography Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Noor Dina Muhd Noor
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Suriana Sabri
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Mohd Shukuri Mohamad Ali
- Enzyme Technology and X-ray Crystallography Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Abu Bakar Salleh
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Siti Nurbaya Oslan
- Enzyme Technology and X-ray Crystallography Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
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14
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Navale AM. Glucose Transporter and Sensor Mechanisms in Fungal Pathogens as Potential Drug Targets. Curr Rev Clin Exp Pharmacol 2024; 19:250-258. [PMID: 37861001 DOI: 10.2174/0127724328263050230923154326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/02/2023] [Accepted: 08/25/2023] [Indexed: 10/21/2023]
Abstract
Fungal infections are emerging as major health challenges in recent years. The development of resistance against existing antifungal agents needs urgent attention and action. The limited classes of antifungal drugs available, their tendency to cause adverse effects, lack of effectiveness, etc., are the major limitations of current therapy. Thus, there is a pressing demand for new antifungal drug classes to cope with the present circumstances. Glucose is the key source of energy for all organisms, including fungi. Glucose plays a crucial role as a source of carbon and energy for processes like virulence, growth, invasion, biofilm formation, and resistance development. The glucose transport and sensing mechanisms are well developed in these organisms as an important strategy to sustain survival. Modulating these transport or sensor mechanisms may serve as an important strategy to inhibit fungal growth. Moreover, the structural difference between human and fungal glucose transporters makes them more appealing as drug targets. Limited literature is available for fungal glucose entry mechanisms. This review provides a comprehensive account of sugar transport mechanisms in common fungal pathogens.
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Affiliation(s)
- Archana Mohit Navale
- Department of Pharmacology, Parul Institute of Pharmacy, Parul University, Limda, India
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15
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Sah SK, Yadav A, Kruppa MD, Rustchenko E. Identification of 10 genes on Candida albicans chromosome 5 that control surface exposure of the immunogenic cell wall epitope β-glucan and cell wall remodeling in caspofungin-adapted mutants. Microbiol Spectr 2023; 11:e0329523. [PMID: 37966256 PMCID: PMC10714753 DOI: 10.1128/spectrum.03295-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/10/2023] [Indexed: 11/16/2023] Open
Abstract
IMPORTANCE Candida infections are often fatal in immuno-compromised individuals, resulting in many thousands of deaths per year. Caspofungin has proven to be an excellent anti-Candida drug and is now the frontline treatment for infections. However, as expected, the number of resistant cases is increasing; therefore, new treatment modalities are needed. We are determining metabolic pathways leading to decreased drug susceptibility in order to identify mechanisms facilitating evolution of clinical resistance. This study expands the understanding of genes that modulate drug susceptibility and reveals new targets for the development of novel antifungal drugs.
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Affiliation(s)
- Sudisht K. Sah
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York, USA
| | - Anshuman Yadav
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York, USA
| | - Michael D. Kruppa
- Department of Biomedical Sciences, Center of Excellence in Inflammation, Infectious Disease and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, USA
| | - Elena Rustchenko
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York, USA
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16
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Mohamed SH, Fu MS, Hain S, Alselami A, Vanhoffelen E, Li Y, Bojang E, Lukande R, Ballou ER, May RC, Ding C, Velde GV, Drummond RA. Microglia are not protective against cryptococcal meningitis. Nat Commun 2023; 14:7202. [PMID: 37938547 PMCID: PMC10632471 DOI: 10.1038/s41467-023-43061-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 10/30/2023] [Indexed: 11/09/2023] Open
Abstract
Microglia provide protection against a range of brain infections including bacteria, viruses and parasites, but how these glial cells respond to fungal brain infections is poorly understood. We investigated the role of microglia in the context of cryptococcal meningitis, the most common cause of fungal meningitis in humans. Using a series of transgenic- and chemical-based microglia depletion methods we found that, contrary to their protective role during other infections, loss of microglia did not affect control of Cryptococcus neoformans brain infection which was replicated with several fungal strains. At early time points post-infection, we found that microglia depletion lowered fungal brain burdens, which was related to intracellular residence of C. neoformans within microglia. Further examination of extracellular and intracellular fungal populations revealed that C. neoformans residing in microglia were protected from copper starvation, whereas extracellular yeast upregulated copper transporter CTR4. However, the degree of copper starvation did not equate to fungal survival or abundance of metals within different intracellular niches. Taken together, these data show how tissue-resident myeloid cells may influence fungal phenotype in the brain but do not provide protection against this infection, and instead may act as an early infection reservoir.
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Affiliation(s)
- Sally H Mohamed
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK
| | - Man Shun Fu
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK
| | - Sofia Hain
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK
| | - Alanoud Alselami
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK
| | - Eliane Vanhoffelen
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium
| | - Yanjian Li
- College of Life and Health Sciences, Northeastern University, Shenyang, 110015, Liaoning, China
| | - Ebrima Bojang
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK
| | - Robert Lukande
- Department of Pathology, College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - Robin C May
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Birmingham, UK
| | - Chen Ding
- College of Life and Health Sciences, Northeastern University, Shenyang, 110015, Liaoning, China
| | - Greetje Vande Velde
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium
| | - Rebecca A Drummond
- Institute of Immunology & Immunotherapy, University of Birmingham, Birmingham, UK.
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Birmingham, UK.
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17
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Child HT, Deeks MJ, Rudd JJ, Bates S. Comparison of the impact of two key fungal signalling pathways on Zymoseptoria tritici infection reveals divergent contribution to invasive growth through distinct regulation of infection-associated genes. MOLECULAR PLANT PATHOLOGY 2023; 24:1220-1237. [PMID: 37306534 PMCID: PMC10502814 DOI: 10.1111/mpp.13365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 06/13/2023]
Abstract
The lifecycle of Zymoseptoria tritici requires a carefully regulated asymptomatic phase within the wheat leaf following penetration of the mesophyll via stomata. Here we compare the roles in this process of two key fungal signalling pathways, mutants of which were identified through forward genetics due to their avirulence on wheat. Whole-genome resequencing of avirulent Z. tritici T-DNA transformants identified disruptive mutations in ZtBCK1 from the kinase cascade of the cell wall integrity (CWI) pathway, and the adenylate cyclase gene ZtCYR1. Targeted deletion of these genes abolished the pathogenicity of the fungus and led to similar in vitro phenotypes to those associated with disruption of putative downstream kinases, both supporting previous studies and confirming the importance of these pathways in virulence. RNA sequencing was used to investigate the effect of ZtBCK1 and ZtCYR1 deletion on gene expression in both the pathogen and host during infection. ZtBCK1 was found to be required for the adaptation to the host environment, controlling expression of infection-associated secreted proteins, including known virulence factors. Meanwhile, ZtCYR1 is implicated in controlling the switch to necrotrophy, regulating expression of effectors associated with this transition. This represents the first study to compare the influence of CWI and cAMP signalling on in planta transcription of a fungal plant pathogen, providing insights into their differential regulation of candidate effectors during invasive growth.
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Affiliation(s)
| | | | - Jason J. Rudd
- Department of Protecting Crops and the EnvironmentRothamsted ResearchHarpendenUK
| | - Steven Bates
- Department of BiosciencesUniversity of ExeterExeterUK
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Novy E, Esposito M, Birckener J, Germain A, Losser MR, Machouart MC, Guerci P. Reappraisal of intra-abdominal candidiasis: insights from peritoneal fluid analysis. Intensive Care Med Exp 2023; 11:67. [PMID: 37776390 PMCID: PMC10542081 DOI: 10.1186/s40635-023-00552-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/22/2023] [Indexed: 10/02/2023] Open
Abstract
BACKGROUND The understanding of high mortality associated with intra-abdominal candidiasis (IAC) remains limited. While Candida is considered a harmless colonizer in the digestive tract, its role as a true pathogen in IAC is still debated. Evidence regarding Candida virulence in the human peritoneal fluid are lacking. We hypothesized that during IAC, Candida albicans develops virulence factors to survive to new environmental conditions. The objective of this observational exploratory monocentric study is to investigate the influence of peritoneal fluid (PF) on the expression of C. albicans virulence using a multimodal approach. MATERIALS AND METHODS A standardized inoculum of a C. albicans (3.106 UFC/mL) reference strain (SC5314) was introduced in vitro into various PF samples obtained from critically ill patients with intra-abdominal infection. Ascitic fluids (AFs) and Sabouraud medium (SBD) were used as control groups. Optical microscopy and conventional culture techniques were employed to assess the morphological changes and growth of C. albicans. Reverse transcriptase qPCR was utilized to quantify the expression levels of five virulence genes. The metabolic production of C. albicans was measured using the calScreener™ technology. RESULTS A total of 26 PF samples from patients with secondary peritonitis were included in the study. Critically ill patients were mostly male (73%) with a median age of 58 years admitted for urgent surgery (78%). Peritonitis was mostly hospital-acquired (81%), including 13 post-operative peritonitis (50%). The infected PF samples predominantly exhibited polymicrobial composition. The findings revealed substantial variability in C. albicans growth and morphological changes in the PF compared to ascitic fluid. Virulence gene expression and metabolic production were dependent on the specific PF sample and the presence of bacterial coinfection. CONCLUSIONS This study provides evidence of C. albicans virulence expression in the peritoneal fluid. The observed variability in virulence expression suggests that it is influenced by the composition of PF and the presence of bacterial coinfection. These findings contribute to a better understanding of the complex dynamics of intra-abdominal candidiasis and advocate for personalized approach for IAC patients. Trial registration https://clinicaltrials.gov/ (NCT05264571; February 22, 2022).
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Affiliation(s)
- Emmanuel Novy
- Service d'anesthésie-Réanimation et Médecine Péri-Opératoire, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France.
- SIMPA, UR7300, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France.
| | - Mathieu Esposito
- Service d'anesthésie-Réanimation et Médecine Péri-Opératoire, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
- SIMPA, UR7300, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France
| | - Julien Birckener
- Service d'anesthésie-Réanimation et Médecine Péri-Opératoire, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
| | - Adeline Germain
- Service de Chirurgie Digestive, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
- NGERE, U1256, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France
| | - Marie-Reine Losser
- Service d'anesthésie-Réanimation et Médecine Péri-Opératoire, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
- DCAC, INSERM 1116, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France
| | - Marie-Claire Machouart
- SIMPA, UR7300, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France
- Service de Mycologie et Parasitologie, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
| | - Philippe Guerci
- Service d'anesthésie-Réanimation et Médecine Péri-Opératoire, CHRU Nancy, Hôpitaux de Brabois, 54500, Vandœuvre-Lès-Nancy, France
- DCAC, INSERM 1116, Université de Lorraine, 54500, Vandœuvre-Lès-Nancy, France
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19
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Anaya EU, Amin AE, Wester MJ, Danielson ME, Michel KS, Neumann AK. Dectin-1 multimerization and signaling depends on fungal β-glucan structure and exposure. Biophys J 2023; 122:3749-3767. [PMID: 37515324 PMCID: PMC10541497 DOI: 10.1016/j.bpj.2023.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 06/30/2023] [Accepted: 07/25/2023] [Indexed: 07/30/2023] Open
Abstract
Dectin-1A is a C-type lectin innate immunoreceptor that recognizes β-(1,3;1,6)-glucan, a structural component of Candida species cell walls. β-Glucans can adopt solution structures ranging from random coil to insoluble fiber due to tertiary (helical) and quaternary structure. Fungal β-glucans of medium and high molecular weight are highly structured, but low molecular weight glucan is much less structured. Despite similar affinity for Dectin-1, the ability of glucans to induce Dectin-1A-mediated signaling correlates with degree of structure. Glucan denaturation experiments showed that glucan structure determines agonistic potential, but not receptor binding affinity. We explored the impact of glucan structure on molecular aggregation of Dectin-1A. Stimulation with glucan signaling decreased Dectin-1A diffusion coefficient. Fluorescence measurements provided direct evidence of ligation-induced Dectin-1A aggregation, which positively correlated with increasing glucan structure content. In contrast, Dectin-1A is predominantly in a low aggregation state in resting cells. Molecular aggregates formed during interaction with highly structured, agonistic glucans did not exceed relatively small (<15 nm) clusters of a few engaged receptors. Finally, we observed increased molecular aggregation of Dectin-1A at fungal particle contact sites in a manner that positively correlated with the degree of exposed glucan on the particle surface. These results indicate that Dectin-1A senses the solution conformation of β-glucans through their varying ability to drive receptor dimer/oligomer formation and activation of membrane proximal signaling events.
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Affiliation(s)
- Eduardo U Anaya
- Department of Pathology, University of New Mexico, School of Medicine, Albuquerque, New Mexico
| | - Akram Etemadi Amin
- Department of Pathology, University of New Mexico, School of Medicine, Albuquerque, New Mexico; Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico
| | - Michael J Wester
- Department of Mathematics and Statistics, University of New Mexico, Albuquerque, New Mexico
| | | | | | - Aaron K Neumann
- Department of Pathology, University of New Mexico, School of Medicine, Albuquerque, New Mexico.
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20
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Wagner AS, Lumsdaine SW, Mangrum MM, Reynolds TB. Caspofungin-induced β(1,3)-glucan exposure in Candida albicans is driven by increased chitin levels. mBio 2023; 14:e0007423. [PMID: 37377417 PMCID: PMC10470516 DOI: 10.1128/mbio.00074-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 05/04/2023] [Indexed: 06/29/2023] Open
Abstract
To successfully induce disease, Candida albicans must effectively evade the host immune system. One mechanism used by C. albicans to achieve this is to mask immunogenic β(1,3)-glucan epitopes within its cell wall under an outer layer of mannosylated glycoproteins. Consequently, induction of β(1,3)-glucan exposure (unmasking) via genetic or chemical manipulation increases fungal recognition by host immune cells in vitro and attenuates disease during systemic infection in mice. Treatment with the echinocandin caspofungin is one of the most potent drivers of β(1,3)-glucan exposure. Several reports using murine infection models suggest a role for the immune system, and specifically host β(1,3)-glucan receptors, in mediating the efficacy of echinocandin treatment in vivo. However, the mechanism by which caspofungin-induced unmasking occurs is not well understood. In this report, we show that foci of unmasking co-localize with areas of increased chitin within the yeast cell wall in response to caspofungin, and that inhibition of chitin synthesis via nikkomycin Z attenuates caspofungin-induced β(1,3)-glucan exposure. Furthermore, we find that both the calcineurin and Mkc1 mitogen-activated protein kinase pathways work synergistically to regulate β(1,3)-glucan exposure and chitin synthesis in response to drug treatment. When either of these pathways are interrupted, it results in a bimodal population of cells containing either high or low chitin content. Importantly, increased unmasking correlates with increased chitin content within these cells. Microscopy further indicates that caspofungin-induced unmasking correlates with actively growing cells. Collectively, our work presents a model in which chitin synthesis induces unmasking within the cell wall in response to caspofungin in growing cells. IMPORTANCE Systemic candidiasis has reported mortality rates ranging from 20% to 40%. The echinocandins, including caspofungin, are first-line antifungals used to treat systemic candidiasis. However, studies in mice have shown that echinocandin efficacy relies on both its cidal impacts on Candida albicans, as well as a functional immune system to successfully clear invading fungi. In addition to direct C. albicans killing, caspofungin increases exposure (unmasking) of immunogenic β(1,3)-glucan moieties. To evade immune detection, β(1,3)-glucan is normally masked within the C. albicans cell wall. Consequently, unmasked β(1,3)-glucan renders these cells more visible to the host immune system and attenuates disease progression. Therefore, discovery of how caspofungin-induced unmasking occurs is needed to elucidate how the drug facilitates host immune system-mediated clearance in vivo. We report a strong and consistent correlation between chitin deposition and unmasking in response to caspofungin and propose a model in which altered chitin synthesis drives increased unmasking during drug exposure.
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Affiliation(s)
- Andrew S. Wagner
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | | | - Mikayla M. Mangrum
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Todd B. Reynolds
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
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21
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Corrêa-Junior D, de Andrade IB, Alves V, Avellar-Moura I, Rodrigues-Alves T, de Souza Rabello VB, de S Araújo GR, Borba-Santos LP, Zancopé-Oliveira RM, Almeida-Paes R, Frases S. Metabolic Plasticity and Virulence-Associated Factors of Sporothrix brasiliensis Strains Related to Familiar Outbreaks of Cat-to-Human Transmitted Sporotrichosis. J Fungi (Basel) 2023; 9:724. [PMID: 37504713 PMCID: PMC10381138 DOI: 10.3390/jof9070724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 06/30/2023] [Accepted: 06/30/2023] [Indexed: 07/29/2023] Open
Abstract
Sporothrix brasiliensis is the main agent of zoonotic sporotrichosis transmitted by domestic cats in South America. In humans, sporotrichosis commonly presents with cutaneous or lymphocutaneous lesions, and in cats, with multiple ulcerated skin lesions associated with enlarged lymph nodes and respiratory signs. Fungal virulence factors may affect the clinical presentation of the mycoses. Sporothrix spp. present some virulence factors. This study aims to compare 24 S. brasiliensis strains from 12 familiar outbreaks of cat-to-human transmitted sporotrichosis. Fungal growth in different substrates, thermotolerance, resistance to oxidative stress, and production of enzymes were evaluated. An invertebrate model of experimental infection was used to compare the virulence of the strains. The strains grew well on glucose and N-acetyl-D-glucosamine but poorly on lactate. Their thermotolerance was moderate to high. All strains were susceptible to hydrogen peroxide, and the majority produced hemolysins but not phospholipase and esterase. There was no significant difference in the putative virulence-associated factors studied among the different hosts. Moreover, strains isolated from a human and a cat from four familiar outbreaks presented a very similar profile of expression of these factors, reinforcing the zoonotic transmission of S. brasiliensis in Brazil and demonstrating the plasticity of this species in the production of virulence factors.
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Affiliation(s)
- Dario Corrêa-Junior
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Iara Bastos de Andrade
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Vinicius Alves
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Igor Avellar-Moura
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Tânia Rodrigues-Alves
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Vanessa Brito de Souza Rabello
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 24020-141, Brazil
| | - Glauber R de S Araújo
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Luana Pereira Borba-Santos
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 24020-141, Brazil
| | - Rosely Maria Zancopé-Oliveira
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro 21041-210, Brazil
| | - Rodrigo Almeida-Paes
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro 21041-210, Brazil
- Rede Micologia RJ, FAPERJ, Rio de Janeiro 20020-000, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Rede Micologia RJ, FAPERJ, Rio de Janeiro 20020-000, Brazil
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22
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Larcombe DE, Bohovych IM, Pradhan A, Ma Q, Hickey E, Leaves I, Cameron G, Avelar GM, de Assis LJ, Childers DS, Bain JM, Lagree K, Mitchell AP, Netea MG, Erwig LP, Gow NAR, Brown AJP. Glucose-enhanced oxidative stress resistance-A protective anticipatory response that enhances the fitness of Candida albicans during systemic infection. PLoS Pathog 2023; 19:e1011505. [PMID: 37428810 PMCID: PMC10358912 DOI: 10.1371/journal.ppat.1011505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 07/20/2023] [Accepted: 06/22/2023] [Indexed: 07/12/2023] Open
Abstract
Most microbes have developed responses that protect them against stresses relevant to their niches. Some that inhabit reasonably predictable environments have evolved anticipatory responses that protect against impending stresses that are likely to be encountered in their niches-termed "adaptive prediction". Unlike yeasts such as Saccharomyces cerevisiae, Kluyveromyces lactis and Yarrowia lipolytica and other pathogenic Candida species we examined, the major fungal pathogen of humans, Candida albicans, activates an oxidative stress response following exposure to physiological glucose levels before an oxidative stress is even encountered. Why? Using competition assays with isogenic barcoded strains, we show that "glucose-enhanced oxidative stress resistance" phenotype enhances the fitness of C. albicans during neutrophil attack and during systemic infection in mice. This anticipatory response is dependent on glucose signalling rather than glucose metabolism. Our analysis of C. albicans signalling mutants reveals that the phenotype is not dependent on the sugar receptor repressor pathway, but is modulated by the glucose repression pathway and down-regulated by the cyclic AMP-protein kinase A pathway. Changes in catalase or glutathione levels do not correlate with the phenotype, but resistance to hydrogen peroxide is dependent on glucose-enhanced trehalose accumulation. The data suggest that the evolution of this anticipatory response has involved the recruitment of conserved signalling pathways and downstream cellular responses, and that this phenotype protects C. albicans from innate immune killing, thereby promoting the fitness of C. albicans in host niches.
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Affiliation(s)
- Daniel E. Larcombe
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Iryna M. Bohovych
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Arnab Pradhan
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Qinxi Ma
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Emer Hickey
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Gary Cameron
- Rowett Institute, School of Medicine Medical Sciences & Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Gabriela M. Avelar
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Leandro J. de Assis
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Delma S. Childers
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Judith M. Bain
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Katherine Lagree
- Department of Microbiology, Biosciences Building, University of Georgia, Athens, Georgia, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, Biosciences Building, University of Georgia, Athens, Georgia, United States of America
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - Lars P. Erwig
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Johnson-Johnson Innovation, EMEA Innovation Centre, One Chapel Place, London, United Kingdom
| | - Neil A. R. Gow
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Alistair J. P. Brown
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
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23
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Wu H, Wang L, Wang W, Shao Z, Jia X, Xiao H, Chen J. The secretory Candida effector Sce1 licenses fungal virulence by masking the immunogenic β-1,3-glucan and promoting apoptosis of the host cells. MLIFE 2023; 2:159-177. [PMID: 38817625 PMCID: PMC10989805 DOI: 10.1002/mlf2.12066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/28/2023] [Accepted: 04/05/2023] [Indexed: 06/01/2024]
Abstract
Candida albicans deploys a variety of mechanisms such as morphological switch and elicitor release to promote virulence. However, the intricate interactions between the fungus and the host remain poorly understood, and a comprehensive inventory of fungal virulence factors has yet to be established. In this study, we identified a C. albicans secretory effector protein Sce1, whose induction and secretion are associated with vagina-simulative conditions and chlamydospore formation. Sequence alignment showed that Sce1 belongs to a Pir family in C. albicans, which is conserved across several fungi and primarily characterized as a β-glucan binding protein in the Saccharomyces cerevisiae. Mechanically, Sce1 is primarily localized to the cell wall in a cleaved form as an alkali-labile β-1,3-glucan binding protein and plays a role in masking β-glucan in acidic environments and chlamydospores, a feature that might underline C. albicans' ability to evade host immunity. Further, a cleaved short form of Sce1 protein could be released into extracellular compartments and presented in bone marrow-derived macrophages infected with chlamydospores. This cleaved short form of Sce1 also demonstrated a unique ability to trigger the caspases-8/9-dependent apoptosis in various host cells. Correspondingly, genetic deletion of SCE1 led to dampened vaginal colonization of C. albicans and diminished fungal virulence during systemic infection. The discovery of Sce1 as a versatile virulence effector that executes at various compartments sheds light on the fungus-host interactions and C. albicans pathogenesis.
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Affiliation(s)
- Hongyu Wu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
| | - Li Wang
- The Center for Microbes, Development and Health, Institut Pasteur of Shanghai, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
- Clinical Medicine Scientific and Technical Innovation Center, Shanghai Tenth People's HospitalTongji University School of MedicineShanghaiChina
| | - Wenjuan Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
| | - Zhugui Shao
- The Center for Microbes, Development and Health, Institut Pasteur of Shanghai, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical SciencesShandong UniversityJinanChina
| | - Xin‐Ming Jia
- Clinical Medicine Scientific and Technical Innovation Center, Shanghai Tenth People's HospitalTongji University School of MedicineShanghaiChina
| | - Hui Xiao
- The Center for Microbes, Development and Health, Institut Pasteur of Shanghai, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
| | - Jiangye Chen
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina
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24
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Seelbinder B, Lohinai Z, Vazquez-Uribe R, Brunke S, Chen X, Mirhakkak M, Lopez-Escalera S, Dome B, Megyesfalvi Z, Berta J, Galffy G, Dulka E, Wellejus A, Weiss GJ, Bauer M, Hube B, Sommer MOA, Panagiotou G. Candida expansion in the gut of lung cancer patients associates with an ecological signature that supports growth under dysbiotic conditions. Nat Commun 2023; 14:2673. [PMID: 37160893 PMCID: PMC10169812 DOI: 10.1038/s41467-023-38058-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 04/11/2023] [Indexed: 05/11/2023] Open
Abstract
Candida species overgrowth in the human gut is considered a prerequisite for invasive candidiasis, but our understanding of gut bacteria promoting or restricting this overgrowth is still limited. By integrating cross-sectional mycobiome and shotgun metagenomics data from the stool of 75 male and female cancer patients at risk but without systemic candidiasis, bacterial communities in high Candida samples display higher metabolic flexibility yet lower contributional diversity than those in low Candida samples. We develop machine learning models that use only bacterial taxa or functional relative abundances to predict the levels of Candida genus and species in an external validation cohort with an AUC of 78.6-81.1%. We propose a mechanism for intestinal Candida overgrowth based on an increase in lactate-producing bacteria, which coincides with a decrease in bacteria that regulate short chain fatty acid and oxygen levels. Under these conditions, the ability of Candida to harness lactate as a nutrient source may enable Candida to outcompete other fungi in the gut.
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Affiliation(s)
- Bastian Seelbinder
- Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology- Hans Knöll Institute, Jena, Germany
| | - Zoltan Lohinai
- National Koranyi Institute of Pulmonology, Budapest, Hungary
- Translational Medicine Institute, Semmelweis University, Budapest, Hungary
| | - Ruben Vazquez-Uribe
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Sascha Brunke
- Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Jena, Germany
| | - Xiuqiang Chen
- Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology- Hans Knöll Institute, Jena, Germany
| | - Mohammad Mirhakkak
- Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology- Hans Knöll Institute, Jena, Germany
| | - Silvia Lopez-Escalera
- Chr. Hansen A/S, Human Health Innovation, Hoersholm, Denmark
- Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Balazs Dome
- National Koranyi Institute of Pulmonology, Budapest, Hungary
- Department of Thoracic Surgery, Medical University of Vienna, Vienna, Austria
- Department of Thoracic Surgery, National Institute of Oncology-Semmelweis University, Budapest, Hungary
| | - Zsolt Megyesfalvi
- National Koranyi Institute of Pulmonology, Budapest, Hungary
- Department of Thoracic Surgery, Medical University of Vienna, Vienna, Austria
- Department of Thoracic Surgery, National Institute of Oncology-Semmelweis University, Budapest, Hungary
| | - Judit Berta
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | | | - Edit Dulka
- County Hospital of Torokbalint, Torokbalint, Hungary
| | - Anja Wellejus
- Chr. Hansen A/S, Human Health Innovation, Hoersholm, Denmark
| | - Glen J Weiss
- Department of Medicine, UMass Chan Medical School, Worcester, MA, USA
| | - Michael Bauer
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Bernhard Hube
- Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Jena, Germany
- Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Morten O A Sommer
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Gianni Panagiotou
- Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology- Hans Knöll Institute, Jena, Germany.
- Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany.
- Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China.
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25
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MacAlpine J, Robbins N, Cowen LE. Bacterial-fungal interactions and their impact on microbial pathogenesis. Mol Ecol 2023; 32:2565-2581. [PMID: 35231147 PMCID: PMC11032213 DOI: 10.1111/mec.16411] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/14/2022] [Accepted: 02/18/2022] [Indexed: 11/27/2022]
Abstract
Microbial communities of the human microbiota exhibit diverse effects on human health and disease. Microbial homeostasis is important for normal physiological functions and changes to the microbiota are associated with many human diseases including diabetes, cancer, and colitis. In addition, there are many microorganisms that are either commensal or acquired from environmental reservoirs that can cause diverse pathologies. Importantly, the balance between health and disease is intricately connected to how members of the microbiota interact and affect one another's growth and pathogenicity. However, the mechanisms that govern these interactions are only beginning to be understood. In this review, we outline bacterial-fungal interactions in the human body, including examining the mechanisms by which bacteria govern fungal growth and virulence, as well as how fungi regulate bacterial pathogenesis. We summarize advances in the understanding of chemical, physical, and protein-based interactions, and their role in exacerbating or impeding human disease. We focus on the three fungal species responsible for the majority of systemic fungal infections in humans: Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus. We conclude by summarizing recent studies that have mined microbes for novel antimicrobials and antivirulence factors, highlighting the potential of the human microbiota as a rich resource for small molecule discovery.
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Affiliation(s)
- Jessie MacAlpine
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
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26
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Pedro NA, Fontebasso G, Pinto SN, Alves M, Mira NP. Acetate modulates the inhibitory effect of Lactobacillus gasseri against the pathogenic yeasts Candida albicans and Candida glabrata. MICROBIAL CELL (GRAZ, AUSTRIA) 2023; 10:88-102. [PMID: 37009625 PMCID: PMC10054710 DOI: 10.15698/mic2023.04.795] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/10/2023] [Accepted: 03/16/2023] [Indexed: 04/04/2023]
Abstract
The exploration of the interference prompted by commensal bacteria over fungal pathogens is an interesting alternative to develop new therapies. In this work we scrutinized how the presence of the poorly studied vaginal species Lactobacillus gasseri affects relevant pathophysiological traits of Candida albicans and Candida glabrata. L. gasseri was found to form mixed biofilms with C. albicans and C. glabrata resulting in pronounced death of the yeast cells, while bacterial viability was not affected. Reduced viability of the two yeasts was also observed upon co-cultivation with L. gasseri under planktonic conditions. Either in planktonic cultures or in biofilms, the anti-Candida effect of L. gasseri was augmented by acetate in a concentration-dependent manner. During planktonic co-cultivation the two Candida species counteracted the acidification prompted by L. gasseri thus impacting the balance between dissociated and undissociated organic acids. This feature couldn't be phenocopied in single-cultures of L. gasseri resulting in a broth enriched in acetic acid, while in the co-culture the non-toxic acetate prevailed. Altogether the results herein described advance the design of new anti-Candida therapies based on probiotics, in particular, those based on vaginal lactobacilli species, helping to reduce the significant burden that infections caused by Candida have today in human health.
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Affiliation(s)
- Nuno A. Pedro
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico – Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Gabriela Fontebasso
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico – Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Sandra N. Pinto
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico – Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Marta Alves
- CQE-Centro Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Nuno P. Mira
- iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico – Department of Bioengineering, Universidade de Lisboa, 1049-001 Lisboa, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- * Corresponding Author: Nuno P Mira, Instituto Superior Técnico, Department of Bioengineering, University of Lisbon, Portugal; E-mail:
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27
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Abstract
The fungal cell wall is essential for growth and survival, and is a key target for antifungal drugs and the immune system. The cell wall must be robust but flexible, protective and shielding yet porous to nutrients and membrane vesicles and receptive to exogenous signals. Most fungi have a common inner wall skeleton of chitin and β-glucans that functions as a flexible viscoelastic frame to which a more diverse set of outer cell wall polymers and glycosylated proteins are attached. Whereas the inner wall largely determines shape and strength, the outer wall confers properties of hydrophobicity, adhesiveness, and chemical and immunological heterogeneity. The spatial organization and dynamic regulation of the wall in response to prevailing growth conditions enable fungi to thrive within changing, diverse and often hostile environments. Understanding this architecture provides opportunities to develop diagnostics and drugs to combat life-threatening fungal infections.
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Affiliation(s)
- Neil A R Gow
- Medical Research Council Centre for Medical Mycology, School of Biosciences, University of Exeter, Exeter, UK.
| | - Megan D Lenardon
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
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Velazhahan V, McCann BL, Bignell E, Tate CG. Developing novel antifungals: lessons from G protein-coupled receptors. Trends Pharmacol Sci 2023; 44:162-174. [PMID: 36801017 DOI: 10.1016/j.tips.2022.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/15/2022] [Accepted: 12/15/2022] [Indexed: 02/18/2023]
Abstract
Up to 1.5 million people die yearly from fungal disease, but the repertoire of antifungal drug classes is minimal and the incidence of drug resistance is rising rapidly. This dilemma was recently declared by the World Health Organization as a global health emergency, but the discovery of new antifungal drug classes remains excruciatingly slow. This process could be accelerated by focusing on novel targets, such as G protein-coupled receptor (GPCR)-like proteins, that have a high likelihood of being druggable and have well-defined biology and roles in disease. We discuss recent successes in understanding the biology of virulence and in structure determination of yeast GPCRs, and highlight new approaches that might pay significant dividends in the urgent search for novel antifungal drugs.
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Affiliation(s)
- Vaithish Velazhahan
- Medical Research Council (MRC) Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Bethany L McCann
- MRC Centre for Medical Mycology, Stocker Road, University of Exeter, Exeter EX4 4QD, UK
| | - Elaine Bignell
- MRC Centre for Medical Mycology, Stocker Road, University of Exeter, Exeter EX4 4QD, UK.
| | - Christopher G Tate
- Medical Research Council (MRC) Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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Lange T, Kasper L, Gresnigt MS, Brunke S, Hube B. "Under Pressure" - How fungi evade, exploit, and modulate cells of the innate immune system. Semin Immunol 2023; 66:101738. [PMID: 36878023 PMCID: PMC10109127 DOI: 10.1016/j.smim.2023.101738] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Indexed: 03/06/2023]
Abstract
The human immune system uses an arsenal of effector mechanisms to prevent and counteract infections. Yet, some fungal species are extremely successful as human pathogens, which can be attributed to a wide variety of strategies by which these fungi evade, exploit, and modulate the immune system. These fungal pathogens normally are either harmless commensals or environmental fungi. In this review we discuss how commensalism, but also life in an environmental niche without human contact, can drive the evolution of diverse and specialized immune evasion mechanisms. Correspondingly, we discuss the mechanisms contributing to the ability of these fungi to cause superficial to life-threatening infections.
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Affiliation(s)
- Theresa Lange
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Lydia Kasper
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Mark S Gresnigt
- Junior Research Group Adaptive Pathogenicity Strategies, Hans Knoell Institute, Jena, Germany
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany; Institute of Microbiology, Friedrich Schiller University, Jena, Germany.
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The adaptive response to alternative carbon sources in the pathogen Candida albicans involves a remodeling of thiol- and glutathione-dependent redox status. Biochem J 2023; 480:197-217. [PMID: 36625375 DOI: 10.1042/bcj20220505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 01/03/2023] [Accepted: 01/10/2023] [Indexed: 01/11/2023]
Abstract
Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases known as candidiasis. During infection in vivo, Candida albicans must adapt to host microenvironments and this adaptive response is crucial for the survival of this organism, as it facilitates the effective assimilation of alternative carbon sources others than glucose. We performed a global proteomic analysis on the global changes in protein abundance in response to changes in micronutrient levels, and, in parallel, explored changes in the intracellular redox and metabolic status of the cells. We show here that each of the carbon sources considered - glucose, acetate and lactate - induces a unique pattern of response in C. albicans cells, and that some conditions trigger an original and specific adaptive response involving the adaptation of metabolic pathways, but also a complete remodeling of thiol-dependent antioxidant defenses. Protein S-thiolation and the overproduction of reduced glutathione are two components of the response to high glucose concentration. In the presence of acetate, glutathione-dependent oxidative stress occurs, reduced thiol groups bind to proteins, and glutathione is exported out of the cells, these changes probably being triggered by an increase in glutathione-S-transferases. Overall, our results suggest that the role of cellular redox status regulation and defenses against oxidative stress, including the thiol- and glutathione-dependent response, in the adaptive response of C. albicans to alternative carbon sources should be reconsidered.
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The Candida glabrata Parent Strain Trap: How Phenotypic Diversity Affects Metabolic Fitness and Host Interactions. Microbiol Spectr 2023; 11:e0372422. [PMID: 36633405 PMCID: PMC9927409 DOI: 10.1128/spectrum.03724-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Reference strains improve reproducibility by standardizing observations and methodology, which has ultimately led to important insights into fungal pathogenesis. However, recent investigations have highlighted significant genotypic and phenotypic heterogeneity across isolates that influence genetic circuitry and virulence within a species. Candida glabrata is the second leading cause of candidiasis, a life-threatening infection, and undergoes extensive karyotype and phenotypic changes in response to stress. Much of the work conducted on this pathogen has focused on two sequenced strains, CBS138 (ATCC 2001) and BG2. Few studies have compared these strains in detail, but key differences include mating type and altered patterns of expression of EPA adhesins. In fact, most C. glabrata isolates and BG2 are MATa, while CBS138 is MATα. However, it is not known if other phenotypic differences between these strains play a role in our understanding of C. glabrata pathogenesis. Thus, we set out to characterize metabolic, cell wall, and host-interaction attributes for CBS138 and BG2. We found that BG2 utilized a broader range of nitrogen sources and had reduced cell wall size and carbohydrate exposure than CBS138, which we hypothesized results in differences in innate immune interactions and virulence. We observed that, although both strains were phagocytosed to a similar extent, BG2 replicated to higher numbers in macrophages and was more virulent during Galleria mellonella infection than CBS138 in a dose-dependent manner. Interestingly, deletion of SNF3, a major nutrient sensor, did not affect virulence in G. mellonella for BG2, but significantly enhanced larval killing in the CBS138 background compared to the parent strain. Understanding these fundamental differences in metabolism and host interactions will allow more robust conclusions to be drawn in future studies of C. glabrata pathogenesis. IMPORTANCE Reference strains provide essential insights into the mechanisms underlying virulence in fungal pathogens. However, recent studies in Candida albicans and other species have revealed significant genotypic and phenotypic diversity within clinical isolates that are challenging paradigms regarding key virulence factors and their regulation. Candida glabrata is the second leading cause of candidiasis, and many studies use BG2 or CBS138 for their investigations. Therefore, we aimed to characterize important virulence-related phenotypes for both strains that might alter conclusions about C. glabrata pathogenesis. Our study provides context for metabolic and cell wall changes and how these may influence host interaction phenotypes. Understanding these differences is necessary to support robust conclusions about how virulence factors may function in these and other very different strain backgrounds.
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Wang M, Zhang Z, Dong X, Zhu B. Targeting β-glucans, vital components of the Pneumocystis cell wall. Front Immunol 2023; 14:1094464. [PMID: 36845149 PMCID: PMC9947646 DOI: 10.3389/fimmu.2023.1094464] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/16/2023] [Indexed: 02/11/2023] Open
Abstract
β-glucan is the most abundant polysaccharide in the cell wall of Pneumocystis jirovecii, which has attracted extensive attention because of its unique immunobiological characteristics. β-glucan binds to various cell surface receptors, which produces an inflammatory response and accounts for its immune effects. A deeper comprehension of the processes by Pneumocystis β-glucan recognizes its receptors, activates related signaling pathways, and regulates immunity as required. Such understanding will provide a basis for developing new therapies against Pneumocystis. Herein, we briefly review the structural composition of β-glucans as a vital component of the Pneumocystis cell wall, the host immunity mediated by β-glucans after their recognition, and discuss opportunities for the development of new strategies to combat Pneumocystis.
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Affiliation(s)
- Mengyan Wang
- Department II of Infectious Diseases, Xixi Hospital of Hangzhou, Hangzhou, China,Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhongdong Zhang
- Department II of Infectious Diseases, Xixi Hospital of Hangzhou, Hangzhou, China
| | - Xiaotian Dong
- Department of Clinical Laboratory, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Biao Zhu
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China,*Correspondence: Biao Zhu,
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Sun X, Yu J, Zhu C, Mo X, Sun Q, Yang D, Su C, Lu Y. Recognition of galactose by a scaffold protein recruits a transcriptional activator for the GAL regulon induction in Candida albicans. eLife 2023; 12:84155. [PMID: 36723430 PMCID: PMC9925049 DOI: 10.7554/elife.84155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 01/31/2023] [Indexed: 02/02/2023] Open
Abstract
The GAL pathway of yeasts has long served as a model system for understanding of how regulatory mode of eukaryotic metabolic pathways evolves. While Gal4 mode has been well-characterized in Saccharomycetaceae clade, little is known about the regulation of the GAL pathway in other yeasts. Here, we find that Rep1, a Ndt80-like family transcription factor, serves as a galactose sensor in the commensal-pathogenic fungus Candida albicans. It is presented at the GAL gene promoters independent of the presence of galactose. Rep1 recognizes galactose via a direct physical interaction. The net result of this interaction is the recruitment of a transcriptional activator Cga1 (Candida galactose gene activator, orf19.4959) and transcription of the GAL genes proceeds. Rep1 and Cga1 are conserved across the CTG species. Rep1 itself does not possess transcriptional activity. Instead, it provides a scaffold to recruit different factors for transcriptional regulation. Rep1-Cga1 mode of regulation represents a new example of network rewiring in fungi, which provides insight into how C. albicans evolves transcriptional programs to colonize diverse host niches.
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Affiliation(s)
- Xun Sun
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan UniversityWuhanChina
| | - Jing Yu
- Hubei Key Laboratory of Cell Homeostasis, Wuhan UniversityWuhanChina
| | - Cheng Zhu
- Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, Tianjin UniversityTianjinChina
| | - Xinreng Mo
- Hubei Key Laboratory of Cell Homeostasis, Wuhan UniversityWuhanChina
| | - Qiangqiang Sun
- Hubei Key Laboratory of Cell Homeostasis, Wuhan UniversityWuhanChina
| | - Dandan Yang
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan UniversityWuhanChina
| | - Chang Su
- Hubei Key Laboratory of Cell Homeostasis, Wuhan UniversityWuhanChina
| | - Yang Lu
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan UniversityWuhanChina
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Brown AJP. Fungal resilience and host-pathogen interactions: Future perspectives and opportunities. Parasite Immunol 2023; 45:e12946. [PMID: 35962618 PMCID: PMC10078341 DOI: 10.1111/pim.12946] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 01/31/2023]
Abstract
We are constantly exposed to the threat of fungal infection. The outcome-clearance, commensalism or infection-depends largely on the ability of our innate immune defences to clear infecting fungal cells versus the success of the fungus in mounting compensatory adaptive responses. As each seeks to gain advantage during these skirmishes, the interactions between host and fungal pathogen are complex and dynamic. Nevertheless, simply compromising the physiological robustness of fungal pathogens reduces their ability to evade antifungal immunity, their virulence, and their tolerance against antifungal therapy. In this article I argue that this physiological robustness is based on a 'Resilience Network' which mechanistically links and controls fungal growth, metabolism, stress resistance and drug tolerance. The elasticity of this network probably underlies the phenotypic variability of fungal isolates and the heterogeneity of individual cells within clonal populations. Consequently, I suggest that the definition of the fungal Resilience Network represents an important goal for the future which offers the clear potential to reveal drug targets that compromise drug tolerance and synergise with current antifungal therapies.
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Affiliation(s)
- Alistair J P Brown
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, UK
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35
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Wang Z, Qu S, Gao D, Shao Q, Nie C, Xing C. A Strategy of On-Demand Immune Activation for Antifungal Treatment Using Near-Infrared Responsive Conjugated Polymer Nanoparticles. NANO LETTERS 2023; 23:326-335. [PMID: 36548213 DOI: 10.1021/acs.nanolett.2c04484] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Pathogenic fungal infection is a major clinical threat because pathogenic fungi have developed resistant mechanisms to evade the innate immune response, especially interactions with macrophages. Herein, a strategy to activate immune responses of macrophages to fungi based on near-infrared (NIR) responsive conjugated polymer nanoparticles (CPNs-M) is reported for antifungal immunotherapy. Under NIR light irradiation, CPNs-M exposes β-glucan on the surface of fungal conidia by photothermal damage and drug released from CPNs-M. The exposed β-glucan elicits macrophage recognition and subsequently activates calcium-calmodulin (Ca2+-CaM) signaling followed by the LC3-associated phagocytosis (LAP) pathway to kill fungal conidia. Consequently, a remarkable elimination of intracellular fugal conidia and successful treatment of fungal pneumonia are achieved. This remote regulation strategy to restore pathogen-immune cell interaction on demand provides a new insight into combatting intractable intracellular infections.
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Affiliation(s)
- Zijuan Wang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Shuyi Qu
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Zhejiang 325035, China
| | - Dong Gao
- Key Laboratory of Hebei Province for Molecular Biophysics, Hebei University of Technology, Tianjin 300130, China
| | - Qi Shao
- Key Laboratory of Hebei Province for Molecular Biophysics, Hebei University of Technology, Tianjin 300130, China
| | - Chenyao Nie
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Zhejiang 325035, China
| | - Chengfen Xing
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
- Key Laboratory of Hebei Province for Molecular Biophysics, Hebei University of Technology, Tianjin 300130, China
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Sun Q, Dong B, Yang D, Yu J, Ren T, Wang T, Yang L, Lu Y, Su C. Zcf24, a zinc-finger transcription factor, is required for lactate catabolism and inhibits commensalism in Candida albicans. Mol Microbiol 2023; 119:112-125. [PMID: 36545847 DOI: 10.1111/mmi.15015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 12/03/2022] [Accepted: 12/03/2022] [Indexed: 12/24/2022]
Abstract
Candida albicans is a normal resident of humans and also a prevalent fungal pathogen. Lactate, a nonfermentative carbon source available in numerous anatomical niches, can be used by C. albicans as a carbon source. However, the key regulator(s) involved in this process remain unknown. Here, through a genetic screen, we report the identification of a transcription factor Zcf24 that is specifically required for lactate utilization in C. albicans. Zcf24 is responsible for the induction of CYB2, a gene encoding lactate dehydrogenase that is essential for lactate catabolism, in response to lactate. Chromatin immunoprecipitation showed a significantly higher signal of Zcf24 on the CYB2 promoter in lactate-grown cells than that in glucose-grown cells. Genome-wide transcription profiling indicates that, in addition to CYB2, Zcf24 regulates genes involved in the β-oxidation of fatty acids, iron transport, and drug transport. Surprisingly, deleting ZCF24 confers enhanced commensal fitness. This could be attributed to Crz1-activated β-glucan masking in the zcf24 mutant. The orthologs of Zcf24 are distributed in species most closely to C. albicans and some filamentous fungal species. Altogether, Zcf24 is the first transcription factor identified to date that regulates lactate catabolism in C. albicans and it is also involved in the regulation of commensalism.
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Affiliation(s)
- Qiangqiang Sun
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bin Dong
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Dandan Yang
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Jing Yu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Tianhao Ren
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Tianxu Wang
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Lianjuan Yang
- Shanghai Dermatology Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yang Lu
- College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Chang Su
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
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de Jongh CA, de Vries TJ, Bikker FJ, Gibbs S, Krom BP. Mechanisms of Porphyromonas gingivalis to translocate over the oral mucosa and other tissue barriers. J Oral Microbiol 2023; 15:2205291. [PMID: 37124549 PMCID: PMC10134951 DOI: 10.1080/20002297.2023.2205291] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
Introduction The oral pathogen Porphyromonas gingivalis is not only associated with periodontitis but also with systemic diseases elsewhere in the body. The mechanisms by which P. gingivalis travels from the oral cavity to other organs in the body are largely unknown. This review describes the four putative mechanisms supported by experimental evidence, which enable translocation of P. gingivalis over the oral mucosa, endothelial barriers and subsequent dissemination into the bloodstream. Mechanisms The first mechanism: proteolytic enzymes secreted by P. gingivalis degrade adhesion molecules between tissue cells, and the extracellular matrix. This weakens the structural integrity of the mucosa and allows P. gingivalis to penetrate the tissue. The second is transcytosis: bacteria actively enter tissue cells and transfer to the next layer or the extracellular space. By travelling from cell to cell, P. gingivalis reaches deeper structures. Thirdly, professional phagocytes take up P. gingivalis and travel to the bloodstream where P. gingivalis is released. Lastly, P. gingivalis can adhere to the hyphae forming Candida albicans. These hyphae can penetrate the mucosal tissue, which may allow P. gingivalis to reach deeper structures. Conclusion More research could elucidate targets to inhibit P. gingivalis dissemination and prevent the onset of various systemic diseases.
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Affiliation(s)
- Caroline A. de Jongh
- Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Teun J. de Vries
- Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Floris J. Bikker
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Susan Gibbs
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Bastiaan P. Krom
- Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- CONTACT Bastiaan P. Krom Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
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González K, Gangapurwala G, Alex J, Vollrath A, Cseresnyés Z, Weber C, Czaplewska JA, Hoeppener S, Svensson CM, Orasch T, Heinekamp T, Guerrero-Sánchez C, Figge MT, Schubert US, Brakhage AA. Targeting of phagolysosomes containing conidia of the fungus Aspergillus fumigatus with polymeric particles. Appl Microbiol Biotechnol 2023; 107:819-834. [PMID: 36480041 PMCID: PMC9842589 DOI: 10.1007/s00253-022-12287-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 12/13/2022]
Abstract
Conidia of the airborne human-pathogenic fungus Aspergillus fumigatus are inhaled by humans. In the lung, they are phagocytosed by alveolar macrophages and intracellularly processed. In macrophages, however, conidia can interfere with the maturation of phagolysosomes to avoid their elimination. To investigate whether polymeric particles (PPs) can reach this intracellular pathogen in macrophages, we formulated dye-labeled PPs with a size allowing for their phagocytosis. PPs were efficiently taken up by RAW 264.7 macrophages and were found in phagolysosomes. When macrophages were infected with conidia prior to the addition of PPs, we found that they co-localized in the same phagolysosomes. Mechanistically, the fusion of phagolysosomes containing PPs with phagolysosomes containing conidia was observed. Increasing concentrations of PPs increased fusion events, resulting in 14% of phagolysosomes containing both conidia and PPs. We demonstrate that PPs can reach conidia-containing phagolysosomes, making these particles a promising carrier system for antimicrobial drugs to target intracellular pathogens. KEY POINTS: • Polymer particles of a size larger than 500 nm are internalized by macrophages and localized in phagolysosomes. • These particles can be delivered to Aspergillus fumigatus conidia-containing phagolysosomes of macrophages. • Enhanced phagolysosome fusion by the use of vacuolin1 can increase particle delivery.
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Affiliation(s)
- Katherine González
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07745 Jena, Germany
| | - Gauri Gangapurwala
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Julien Alex
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Antje Vollrath
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Zoltán Cseresnyés
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - Christine Weber
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Justyna A. Czaplewska
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Stephanie Hoeppener
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Carl-Magnus Svensson
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - Thomas Orasch
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - Thorsten Heinekamp
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - Carlos Guerrero-Sánchez
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Marc Thilo Figge
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07745 Jena, Germany
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - Ulrich S. Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Axel A. Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (Leibniz-HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07745 Jena, Germany
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de Assis LJ, Bain JM, Liddle C, Leaves I, Hacker C, Peres da Silva R, Yuecel R, Bebes A, Stead D, Childers DS, Pradhan A, Mackenzie K, Lagree K, Larcombe DE, Ma Q, Avelar GM, Netea MG, Erwig LP, Mitchell AP, Brown GD, Gow NAR, Brown AJP. Nature of β-1,3-Glucan-Exposing Features on Candida albicans Cell Wall and Their Modulation. mBio 2022; 13:e0260522. [PMID: 36218369 PMCID: PMC9765427 DOI: 10.1128/mbio.02605-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 01/15/2023] Open
Abstract
Candida albicans exists as a commensal of mucosal surfaces and the gastrointestinal tract without causing pathology. However, this fungus is also a common cause of mucosal and systemic infections when antifungal immune defenses become compromised. The activation of antifungal host defenses depends on the recognition of fungal pathogen-associated molecular patterns (PAMPs), such as β-1,3-glucan. In C. albicans, most β-1,3-glucan is present in the inner cell wall, concealed by the outer mannan layer, but some β-1,3-glucan becomes exposed at the cell surface. In response to host signals, such as lactate, C. albicans induces the Xog1 exoglucanase, which shaves exposed β-1,3-glucan from the cell surface, thereby reducing phagocytic recognition. We show here that β-1,3-glucan is exposed at bud scars and punctate foci on the lateral wall of yeast cells, that this exposed β-1,3-glucan is targeted during phagocytic attack, and that lactate-induced masking reduces β-1,3-glucan exposure at bud scars and at punctate foci. β-1,3-Glucan masking depends upon protein kinase A (PKA) signaling. We reveal that inactivating PKA, or its conserved downstream effectors, Sin3 and Mig1/Mig2, affects the amounts of the Xog1 and Eng1 glucanases in the C. albicans secretome and modulates β-1,3-glucan exposure. Furthermore, perturbing PKA, Sin3, or Mig1/Mig2 attenuates the virulence of lactate-exposed C. albicans cells in Galleria. Taken together, the data are consistent with the idea that β-1,3-glucan masking contributes to Candida pathogenicity. IMPORTANCE Microbes that coexist with humans have evolved ways of avoiding or evading our immunological defenses. These include the masking by these microbes of their "pathogen-associated molecular patterns" (PAMPs), which are recognized as "foreign" and used to activate protective immunity. The commensal fungus Candida albicans masks the proinflammatory PAMP β-1,3-glucan, which is an essential component of its cell wall. Most of this β-1,3-glucan is hidden beneath an outer layer of the cell wall on these microbes, but some can become exposed at the fungal cell surface. Using high-resolution confocal microscopy, we examine the nature of the exposed β-1,3-glucan at C. albicans bud scars and at punctate foci on the lateral cell wall, and we show that these features are targeted by innate immune cells. We also reveal that downstream effectors of protein kinase A (Mig1/Mig2, Sin3) regulate the secretion of major glucanases, modulate the levels of β-1,3-glucan exposure, and influence the virulence of C. albicans in an invertebrate model of systemic infection. Our data support the view that β-1,3-glucan masking contributes to immune evasion and the virulence of a major fungal pathogen of humans.
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Affiliation(s)
- Leandro José de Assis
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Judith M. Bain
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Corin Liddle
- Bioimaging Unit, University of Exeter, Exeter, United Kingdom
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | | | - Roberta Peres da Silva
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Raif Yuecel
- Exeter Centre for Cytomics, University of Exeter, Exeter, United Kingdom
| | - Attila Bebes
- Exeter Centre for Cytomics, University of Exeter, Exeter, United Kingdom
| | - David Stead
- Aberdeen Proteomics Facility, Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | - Delma S. Childers
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Arnab Pradhan
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Kevin Mackenzie
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Katherine Lagree
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Daniel E. Larcombe
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Qinxi Ma
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Gabriela Mol Avelar
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Mihai G. Netea
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, Netherlands
- Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Lars P. Erwig
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Johnson-Johnson Innovation, EMEA Innovation Centre, London, United Kingdom
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Gordon D. Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Neil A. R. Gow
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Alistair J. P. Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
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Chang W, Zhang M, Jin X, Zhang H, Zheng H, Zheng S, Qiao Y, Yu H, Sun B, Hou X, Lou H. Inhibition of fungal pathogenicity by targeting the H 2S-synthesizing enzyme cystathionine β-synthase. SCIENCE ADVANCES 2022; 8:eadd5366. [PMID: 36525499 PMCID: PMC9757746 DOI: 10.1126/sciadv.add5366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/16/2022] [Indexed: 06/17/2023]
Abstract
The global emergence of antifungal resistance threatens the limited arsenal of available treatments and emphasizes the urgent need for alternative antifungal agents. Targeting fungal pathogenic functions is an appealing alternative therapeutic strategy. Here, we show that cystathionine β-synthase (CBS), compared with cystathionine γ-lyase, is the major enzyme that synthesizes hydrogen sulfide in the pathogenic fungus Candida albicans. Deletion of CBS leads to deficiencies in resistance to oxidative stress, retarded cell growth, defective hyphal growth, and increased β-glucan exposure, which, together, reduce the pathogenicity of C. albicans. By high-throughput screening, we identified protolichesterinic acid, a natural molecule obtained from a lichen, as an inhibitor of CBS that neutralizes the virulence of C. albicans and exhibits therapeutic efficacy in a murine candidiasis model. These findings support the application of CBS as a potential therapeutic target to fight fungal infections.
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Affiliation(s)
- Wenqiang Chang
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Ming Zhang
- Institute of Medical Science, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Xueyang Jin
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Haijuan Zhang
- School of Pharmacy, Linyi University, Linyi, Shandong Province, China
| | - Hongbo Zheng
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Sha Zheng
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
- The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
| | - Yanan Qiao
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Haina Yu
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Bin Sun
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong Province, China
| | - Xuben Hou
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Hongxiang Lou
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
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Duszenko N, van Willigen DM, Bunschoten A, Velders AH, Roestenberg M, van Leeuwen FWB. Chemically Enhanced Immunogenicity of Bacteria by Supramolecular Functionalization with an Adjuvant. Chembiochem 2022; 23:e202200434. [PMID: 36177993 PMCID: PMC10098600 DOI: 10.1002/cbic.202200434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/29/2022] [Indexed: 01/25/2023]
Abstract
Many pathogens blunt immune responses because they lack immunogenic structural features, which typically results in disease. Here, we show evidence suggesting that pathogen immunogenicity can be chemically enhanced. Using supramolecular host-guest chemistry, we complexed onto the surface of a poorly immunogenic bacterium (Staphylococcus aureus) a TLR7 agonist-based adjuvant. "Adjuvanted" bacteria were readily recognized by macrophages and induced a more pro-inflammatory immunophenotype. Future applications of this concept could yield treatment modalities that bolster the immune system's response to pathogenic microbes.
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Affiliation(s)
- Nikolas Duszenko
- Interventional Molecular Imaging (IMI) Laboratory, Departments of Radiology & Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 RC, Leiden (The, Netherlands
| | - Danny M van Willigen
- Interventional Molecular Imaging (IMI) Laboratory, Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 RC, Leiden (The, Netherlands
| | - Anton Bunschoten
- Laboratory of BioNanoTechnology, Wageningen University & Research, Bornse Weilanden 9, 6708 WG, Wageningen (The, Netherlands
| | - Aldrik H Velders
- Laboratory of BioNanoTechnology, Wageningen University & Research, Bornse Weilanden 9, 6708 WG, Wageningen (The, Netherlands
| | - Meta Roestenberg
- Departments of Parasitology & Infectious Diseases, Leiden University Medical Center, Albinusdreef 2, 2333 RC, Leiden (The, Netherlands
| | - Fijs W B van Leeuwen
- Interventional Molecular Imaging (IMI) Laboratory, Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 RC, Leiden, The Netherlands
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Alonso MF, Bain JM, Rudkin FM, Erwig LP, Brown AJ, Gow NA. The nature of the fungal cargo induces significantly different temporal programmes of macrophage phagocytosis. Cell Surf 2022; 8:100082. [PMID: 36299405 PMCID: PMC9589029 DOI: 10.1016/j.tcsw.2022.100082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/12/2022] [Accepted: 10/12/2022] [Indexed: 11/05/2022] Open
Abstract
Phagocytosis is an essential component of our immune defence against fungal pathogens. Differences in the dynamics of phagocyte migration, recognition, uptake and phagolysosome maturation are dependent on the characteristics of the fungal cargo, and in particular to differences in cell wall composition and cellular morphology. However, studies that have focused on phagocyte interactions with individual fungal species have not enabled comparisons in the kinetics of these interactions to be made between these different species. We therefore used live cell video microscopy to examine the temporal dynamics of phagocytosis for a range of fungal cargoes by thioglycollate-elicited peritoneal macrophages from C57BL/6 mice. Uniform populations of macrophages were challenged at the same time with yeast cells of Candida albicans, Candida glabrata, Saccharomyces cerevisiae and Cryptococcus neoformans (wild-type and an acapsular mutant, cap59Δ), and spores of Aspergillus fumigatus and Mucor circinelloides to enable standardized comparative interactions to be quantified from different stages of phagocytosis. Differences in the rate of uptake of fungal cells varied by up to 26-fold, whilst differences in time to induce phagosome acidification varied by as much as 29-fold. Heat-killing or opsonizing the fungal targets markedly affected the kinetics of the interaction in a species-specific manner. Fungal and macrophage killing assays further revealed cargo-specific differences in phagocytosis and diversity in fungal evasion mechanisms. Therefore, simultaneous assessment of the interaction of macrophages with different fungal pathogens highlighted major differences in the kinetics and growth responses during fungus-phagocyte interactions that are likely to impact on pathogenesis and virulence.
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Affiliation(s)
- María Fernanda Alonso
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Judith M. Bain
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Fiona M. Rudkin
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Lars P. Erwig
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Alistair J.P. Brown
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Neil A.R. Gow
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
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Hall RA, Wallace EW. Post-transcriptional control of fungal cell wall synthesis. Cell Surf 2022; 8:100074. [PMID: 35097244 PMCID: PMC8783092 DOI: 10.1016/j.tcsw.2022.100074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/10/2022] [Accepted: 01/10/2022] [Indexed: 12/21/2022] Open
Abstract
Pathogenic fungi hide from their hosts by camouflage, obscuring immunogenic cell wall components such as beta-glucan with innocuous coverings such as mannoproteins and alpha-glucan that are less readily recognised by the host. Attempts to understand how such processes are regulated have met with varying success. Typically studies focus on understanding the transcriptional response of fungi to either their reservoir environment or the host. However, such approaches do not fully address this research question, due to the layers of post-transcriptional and post-translational regulation that occur within a cell. Although in animals the impact of post-transcriptional and post-translational regulation has been well characterised, our knowledge of these processes in the fungal kingdom is more limited. Mutations in RNA-binding proteins, like Ssd1 and Candida albicans Slr1, affect cell wall composition and fungal virulence indicating that post-transcriptional regulation plays a key role in these processes. Here, we review the current state of knowledge of fungal post-transcriptional regulation, and link this to potential mechanisms of immune evasion by drawing on studies from model yeast and plant pathogenic fungi. We highlight several RNA-binding proteins that regulate cell wall synthesis and could be involved in local translation of cell wall components. Expanding our knowledge on post-transcriptional regulation in human fungal pathogens is essential to fully comprehend fungal virulence strategies and for the design of novel antifungal therapies.
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Affiliation(s)
- Rebecca A. Hall
- Kent Fungal Group, Division of Natural Sciences, School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom
| | - Edward W.J. Wallace
- Institute for Cell Biology and SynthSys, School of Biological Sciences, University of Edinburgh, EH9 3FF, United Kingdom
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Somiah T, Gebremariam HG, Zuo F, Smirnova K, Jonsson AB. Lactate causes downregulation of Helicobacter pylori adhesin genes sabA and labA while dampening the production of proinflammatory cytokines. Sci Rep 2022; 12:20064. [PMID: 36414643 PMCID: PMC9681763 DOI: 10.1038/s41598-022-24311-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/14/2022] [Indexed: 11/24/2022] Open
Abstract
Chronic inflammation induced by Helicobacter pylori is strongly associated with gastric cancer development, which is influenced by both bacterial virulence and host genetics. The sialic acid-binding adhesin SabA and the MUC5AC-binding adhesin LabA are important H. pylori virulence factors that facilitate adhesion of the bacterium, which is a crucial step in colonization. Lactate utilization has been reported to play a key role in the pathogenicity of different bacterial species. However, this is poorly understood in H. pylori. In this study, we investigated the effect of lactate on H. pylori adhesin gene expression and the regulation of host inflammatory cytokines. We show that the bacterial adhesins SabA and LabA were downregulated at the transcriptional level during incubation of H. pylori with lactate. Downregulation of sabA required the involvement of the two-component system ArsRS, while labA was regulated via the CheA/CheY system, indicating differences in the regulation of these genes in response to lactate. The levels of the proinflammatory cytokines TNF and IL-6 in H. pylori-stimulated macrophages were reduced when lactate was present. Interestingly, glucose did not prevent the secretion of these cytokines. Taken together, our data suggest that lactate affects H. pylori adhesin gene expression and the host response upon infection.
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Affiliation(s)
- Tanvi Somiah
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Hanna G. Gebremariam
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Fanglei Zuo
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Ksenija Smirnova
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Ann-Beth Jonsson
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
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Fan F, Liu Y, Liu Y, Lv R, Sun W, Ding W, Cai Y, Li W, Liu X, Qu W. Candida albicans biofilms: antifungal resistance, immune evasion, and emerging therapeutic strategies. Int J Antimicrob Agents 2022; 60:106673. [PMID: 36103915 DOI: 10.1016/j.ijantimicag.2022.106673] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/24/2022] [Accepted: 09/09/2022] [Indexed: 12/14/2022]
Abstract
Candida albicans is a fungal pathogen that can form biofilms on medical devices and host tissue, resulting in serious, life-threatening infections. These fungal biofilms are inherently resistant to traditional antifungal therapies and the host immune system; therefore, biofilm-associated infections are a huge clinical challenge. This review summarizes the most important insights into C. albicans biofilm-associated antifungal drug resistance mechanisms and immune evasion strategies. In addtion, this review also discusses the strategies for antifungal drug use to combat these processes, providing further evidence for novel drugs research and clinical therapies.
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Affiliation(s)
- FangMei Fan
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - Yi Liu
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - YiQing Liu
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - RuiXue Lv
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - Wei Sun
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - WenJing Ding
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - YanXing Cai
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - WeiWei Li
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - Xing Liu
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China
| | - Wei Qu
- Department of Laboratory Medicine, Guiyang Maternity & Child Health Hospital, Guiyang, 550003, China.
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Avelar GM, Dambuza IM, Ricci L, Yuecel R, Mackenzie K, Childers DS, Bain JM, Pradhan A, Larcombe DE, Netea MG, Erwig LP, Brown GD, Duncan SH, Gow NA, Walker AW, Brown AJ. Impact of changes at the Candida albicans cell surface upon immunogenicity and colonisation in the gastrointestinal tract. CELL SURFACE (AMSTERDAM, NETHERLANDS) 2022; 8:100084. [PMID: 36299406 PMCID: PMC9589014 DOI: 10.1016/j.tcsw.2022.100084] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022]
Abstract
The immunogenicity of Candida albicans cells is influenced by changes in the exposure of microbe-associated molecular patterns (MAMPs) on the fungal cell surface. Previously, the degree of exposure on the C. albicans cell surface of the immunoinflammatory MAMP β-(1,3)-glucan was shown to correlate inversely with colonisation levels in the gastrointestinal (GI) tract. This is important because life-threatening systemic candidiasis in critically ill patients often arises from translocation of C. albicans strains present in the patient's GI tract. Therefore, using a murine model, we have examined the impact of gut-related factors upon β-glucan exposure and colonisation levels in the GI tract. The degree of β-glucan exposure was examined by imaging flow cytometry of C. albicans cells taken directly from GI compartments, and compared with colonisation levels. Fungal β-glucan exposure was lower in the cecum than the small intestine, and fungal burdens were correspondingly higher in the cecum. This inverse correlation did not hold for the large intestine. The gut fermentation acid, lactate, triggers β-glucan masking in vitro, leading to attenuated anti-Candida immune responses. Additional fermentation acids are present in the GI tract, including acetate, propionate, and butyrate. We show that these acids also influence β-glucan exposure on C. albicans cells in vitro and, like lactate, they influence β-glucan exposure via Gpr1/Gpa2-mediated signalling. Significantly, C. albicans gpr1Δ gpa2Δ cells displayed elevated β-glucan exposure in the large intestine and a corresponding decrease in fungal burden, consistent with the idea that Gpr1/Gpa2-mediated β-glucan masking influences colonisation of this GI compartment. Finally, extracts from the murine gut and culture supernatants from the mannan grazing gut anaerobe Bacteroides thetaiotaomicron promote β-glucan exposure at the C. albicans cell surface. Therefore, the local microbiota influences β-glucan exposure levels directly (via mannan grazing) and indirectly (via fermentation acids), whilst β-glucan masking appears to promote C. albicans colonisation of the murine large intestine.
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Affiliation(s)
- Gabriela M. Avelar
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Ivy M. Dambuza
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Liviana Ricci
- Microbiome, Food Innovation and Food Security Research Theme, Rowett Institute, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Raif Yuecel
- Iain Fraser Cytometry Centre, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Kevin Mackenzie
- Microscopy & Histology Facility, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Delma S. Childers
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Judith M. Bain
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Arnab Pradhan
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Daniel E. Larcombe
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute (LIMES), University of Bonn, 53115 Bonn, Germany
| | - Lars P. Erwig
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Johnson-Johnson Innovation, EMEA Innovation Centre, One Chapel Place, London W1G 0BG, UK
| | - Gordon D. Brown
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Sylvia H. Duncan
- Microbiome, Food Innovation and Food Security Research Theme, Rowett Institute, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Neil A.R. Gow
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Alan W. Walker
- Microbiome, Food Innovation and Food Security Research Theme, Rowett Institute, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Alistair J.P. Brown
- Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
- Corresponding author at: Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK.
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Denham ST, Brammer B, Chung KY, Wambaugh MA, Bednarek JM, Guo L, Moreau CT, Brown JCS. A dissemination-prone morphotype enhances extrapulmonary organ entry by Cryptococcus neoformans. Cell Host Microbe 2022; 30:1382-1400.e8. [PMID: 36099922 PMCID: PMC9588642 DOI: 10.1016/j.chom.2022.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/01/2022] [Accepted: 08/18/2022] [Indexed: 01/08/2023]
Abstract
Environmental pathogens move from ecological niches to mammalian hosts, requiring adaptation to dramatically different environments. Microbes that disseminate farther, including the fungal meningitis pathogen Cryptococcus neoformans, require additional adaptation to diverse tissues. We demonstrate that the formation of a small C. neoformans morphotype-called "seed" cells due to their colonizing ability-is critical for extrapulmonary organ entry. Seed cells exhibit changes in fungal cell size and surface expression that result in an enhanced macrophage update. Seed cell formation is triggered by environmental factors, including C. neoformans' environmental niche, and pigeon guano with phosphate plays a central role. Seed cells show the enhanced expression of phosphate acquisition genes, and mutants unable to acquire phosphate fail to adopt the seed cell morphotype. Additionally, phosphate can be released by tissue damage, potentially establishing a feed-forward loop of seed cell formation and dissemination. Thus, C. neoformans' size variation represent inducible morphotypes that change host interactions to facilitate microbe spread.
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Affiliation(s)
- Steven T Denham
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Brianna Brammer
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Krystal Y Chung
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Morgan A Wambaugh
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Joseph M Bednarek
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Li Guo
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84112, USA
| | - Christian T Moreau
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Jessica C S Brown
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA.
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Li H, Miao MX, Jia CL, Cao YB, Yan TH, Jiang YY, Yang F. Interactions between Candida albicans and the resident microbiota. Front Microbiol 2022; 13:930495. [PMID: 36204612 PMCID: PMC9531752 DOI: 10.3389/fmicb.2022.930495] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 08/31/2022] [Indexed: 01/09/2023] Open
Abstract
Candida albicans is a prevalent, opportunistic human fungal pathogen. It usually dwells in the human body as a commensal, however, once in its pathogenic state, it causes diseases ranging from debilitating superficial to life-threatening systemic infections. The switch from harmless colonizer to virulent pathogen is, in most cases, due to perturbation of the fungus-host-microbiota interplay. In this review, we focused on the interactions between C. albicans and the host microbiota in the mouth, gut, blood, and vagina. We also highlighted important future research directions. We expect that the evaluation of these interplays will help better our understanding of the etiology of fungal infections and shed new light on the therapeutic approaches.
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Affiliation(s)
- Hao Li
- Department of Pharmacy, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China,Department of Physiology and Pharmacology, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Ming-xing Miao
- Department of Physiology and Pharmacology, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Cheng-lin Jia
- Institute of Vascular Disease, Shanghai TCM-Integrated Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yong-bing Cao
- Institute of Vascular Disease, Shanghai TCM-Integrated Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Tian-hua Yan
- Department of Physiology and Pharmacology, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China,*Correspondence: Tian-hua Yan,
| | - Yuan-ying Jiang
- Department of Pharmacy, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China,Yuan-ying Jiang,
| | - Feng Yang
- Department of Pharmacy, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China,Feng Yang,
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Wagner AS, Lumsdaine SW, Mangrum MM, King AE, Hancock TJ, Sparer TE, Reynolds TB. Cek1 regulates ß(1,3)-glucan exposure through calcineurin effectors in Candida albicans. PLoS Genet 2022; 18:e1010405. [PMID: 36121853 PMCID: PMC9521907 DOI: 10.1371/journal.pgen.1010405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 09/29/2022] [Accepted: 08/30/2022] [Indexed: 11/19/2022] Open
Abstract
In order to successfully induce disease, the fungal pathogen Candida albicans regulates exposure of antigens like the cell wall polysaccharide ß(1,3)-glucan to the host immune system. C. albicans covers (masks) ß(1,3)-glucan with a layer of mannosylated glycoproteins, which aids in immune system evasion by acting as a barrier to recognition by host pattern recognition receptors. Consequently, enhanced ß(1,3)-glucan exposure (unmasking) makes fungal cells more visible to host immune cells and facilitates more robust fungal clearance. However, an understanding of how C. albicans regulates its exposure levels of ß(1,3)-glucan is needed to leverage this phenotype. Signal transduction pathways and their corresponding effector genes mediating these changes are only beginning to be defined. Here, we report that the phosphatase calcineurin mediates unmasking of ß(1,3)-glucan in response to inputs from the Cek1 MAPK pathway and in response to caspofungin exposure. In contrast, calcineurin reduces ß-glucan exposure in response to high levels of extracellular calcium. Thus, depending on the input, calcineurin acts as a switchboard to regulate ß(1,3)-glucan exposure levels. By leveraging these differential ß(1,3)-glucan exposure phenotypes, we identified two novel effector genes in the calcineurin regulon, FGR41 and C1_11990W_A, that encode putative cell wall proteins and mediate masking/unmasking. Loss of either effector caused unmasking and attenuated virulence during systemic infection in mice. Furthermore, immunosuppression restored the colonization decrease seen in mice infected with the fgr41Δ/Δ mutant to wild-type levels, demonstrating a reliance on the host immune system for virulence attenuation. Thus, calcineurin and its downstream regulon are general regulators of unmasking.
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Affiliation(s)
- Andrew S. Wagner
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Stephen W. Lumsdaine
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Mikayla M. Mangrum
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Ainsley E. King
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Trevor J. Hancock
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Timothy E. Sparer
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
| | - Todd B. Reynolds
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, United States of America
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Nazari T, Sadeghi F, Izadi A, Sameni S, Mahmoudi S. COVID-19-associated fungal infections in Iran: A systematic review. PLoS One 2022; 17:e0271333. [PMID: 35816494 PMCID: PMC9273100 DOI: 10.1371/journal.pone.0271333] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 06/29/2022] [Indexed: 12/17/2022] Open
Abstract
Objectives
This systematic review aims to summarize the mycological and clinical features of COVID-19-associated fungal infections (CAFIs) in Iran.
Methods
PubMed, Web of Science, Scopus, Cochrane Library, SID, Magiran, IranDoc, and Google Scholar were searched for Persian and English articles published from January 1, 2020, to November 5, 2021, using a systematic search strategy. Studies on Iranian patients suffering from CAFIs were included in the review.
Results
Twenty-two studies comprising 169 patients were retrieved. Reported CAFIs included candidiasis (85, 50.30%), mucormycosis (35, 20.71%), aspergillosis (29, 17.16%), fusariosis (6, 3.55%), three cases caused by rare pathogens (Rhodotorula mucilaginosa, Diaporthe foeniculina, and Sarocladium kiliense) and 11 (6.51%) uncharacterized mold infections. The most common underlying diseases were diabetes (67/168, 39.88%), cardiovascular diseases (55/168, 32.74%), and hypertension (43/168, 25.59%). The use of antibiotics (111/124, 89.52%), corticosteroids (93/132, 70.44%), and mechanical ventilation (66, 51.16%) were the most common predisposing factors. Totally, 72 (50.35%) of 143 patients with CAFIs died (data were not available for 26 patients).
Conclusion
Fungal infections are evident to be a complication of COVID-19 in Iran; thus, clinicians should consider them as a differential diagnosis, especially in patients with comorbidities and previous antibiotic or corticosteroid use.
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Affiliation(s)
- Tina Nazari
- Department of Medical Geriatrics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sadeghi
- Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Alireza Izadi
- Department of Medical Parasitology and Mycology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
- Medical Mycology and Bacteriology Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Setayesh Sameni
- Department of Medical Sciences, Shahrood Branch, Islamic Azad University, Shahrood, Iran
| | - Shahram Mahmoudi
- Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
- * E-mail: ,
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