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Caldera JR, Tsai CM, Trieu D, Gonzalez C, Hajam IA, Du X, Lin B, Liu GY. The characteristics of pre-existing humoral imprint determine efficacy of S. aureus vaccines and support alternative vaccine approaches. Cell Rep Med 2024; 5:101360. [PMID: 38232694 PMCID: PMC10829788 DOI: 10.1016/j.xcrm.2023.101360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 08/15/2023] [Accepted: 12/10/2023] [Indexed: 01/19/2024]
Abstract
The failure of the Staphylococcus aureus (SA) IsdB vaccine trial can be explained by the recall of non-protective immune imprints from prior SA exposure. Here, we investigate natural human SA humoral imprints to understand their broader impact on SA immunizations. We show that antibody responses against SA cell-wall-associated antigens (CWAs) are non-opsonic, while antibodies against SA toxins are neutralizing. Importantly, the protective characteristics of the antibody imprints accurately predict the failure of corresponding vaccines against CWAs and support vaccination against toxins. In passive immunization platforms, natural anti-SA human antibodies reduce the efficacy of the human monoclonal antibodies suvratoxumab and tefibazumab, consistent with the results of their respective clinical trials. Strikingly, in the absence of specific humoral memory responses, active immunizations are efficacious in both naive and SA-experienced mice. Overall, our study points to a practical and predictive approach to evaluate and develop SA vaccines based on pre-existing humoral imprint characteristics.
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Affiliation(s)
- J R Caldera
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Chih-Ming Tsai
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Desmond Trieu
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Cesia Gonzalez
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Irshad A Hajam
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Xin Du
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Brian Lin
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - George Y Liu
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA; Division of Infectious Diseases, Rady Children's Hospital, San Diego, CA 92123, USA.
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2
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Alfano DN, Miller MJ, Bubeck Wardenburg J. Endothelial ADAM10 utilization defines a molecular pathway of vascular injury in mice with bacterial sepsis. J Clin Invest 2023; 133:e168450. [PMID: 37788087 PMCID: PMC10688991 DOI: 10.1172/jci168450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 09/28/2023] [Indexed: 10/05/2023] Open
Abstract
The endothelium plays a critical role in the host response to infection and has been a focus of investigation in sepsis. While it is appreciated that intravascular thrombus formation, severe inflammation, and loss of endothelial integrity impair tissue oxygenation during sepsis, the precise molecular mechanisms that lead to endothelial injury remain poorly understood. We demonstrate here that endothelial ADAM10 was essential for the pathogenesis of Staphylococcus aureus sepsis, contributing to α-toxin-mediated (Hla-mediated) microvascular thrombus formation and lethality. As ADAM10 is essential for endothelial development and homeostasis, we examined whether other major human sepsis pathogens also rely on ADAM10-dependent pathways in pathogenesis. Mice harboring an endothelium-specific knockout of ADAM10 were protected against lethal Pseudomonas aeruginosa and Streptococcus pneumoniae sepsis, yet remained fully susceptible to group B streptococci and Candida albicans sepsis. These studies illustrate a previously unknown role for ADAM10 in sepsis-associated endothelial injury and suggest that understanding pathogen-specific divergent host pathways in sepsis may enable more precise targeting of disease.
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Affiliation(s)
| | - Mark J. Miller
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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3
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Loredan DG, Devlin JC, Lacey KA, Howard N, Chen Z, Zwack EE, Lin JD, Ruggles KV, Khanna KM, Torres VJ, Loke P. Single-Cell Analysis of CX3CR1+ Cells Reveals a Pathogenic Role for BIRC5+ Myeloid Proliferating Cells Driven by Staphylococcus aureus Leukotoxins. J Immunol 2023; 211:836-843. [PMID: 37466391 PMCID: PMC10450158 DOI: 10.4049/jimmunol.2300166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/30/2023] [Indexed: 07/20/2023]
Abstract
Our previous studies identified a population of stem cell-like proliferating myeloid cells within inflamed tissues that could serve as a reservoir for tissue macrophages to adopt different activation states depending on the microenvironment. By lineage-tracing cells derived from CX3CR1+ precursors in mice during infection and profiling by single-cell RNA sequencing, in this study, we identify a cluster of BIRC5+ myeloid cells that expanded in the liver during chronic infection with either the parasite Schistosoma mansoni or the bacterial pathogen Staphylococcus aureus. In the absence of tissue-damaging toxins, S. aureus infection does not elicit these BIRC5+ cells. Moreover, deletion of BIRC5 from CX3CR1-expressing cells results in improved survival during S. aureus infection. Hence the combination of single-cell RNA sequencing and genetic fate-mapping CX3CR1+ cells revealed a toxin-dependent pathogenic role for BIRC5 in myeloid cells during S. aureus infection.
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Affiliation(s)
- Denis G. Loredan
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
- Vilcek Institute of Graduate Biomedical Sciences, New York University Grossman School of Medicine, New York, NY
| | - Joseph C. Devlin
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
| | - Keenan A. Lacey
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
| | - Nina Howard
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Ze Chen
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
| | - Erin E. Zwack
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
| | - Jian-Da Lin
- Department of Biochemical Science and Technology, College of Life Science, National Taiwan University, Taipei City, Taiwan
- Center for Computational and Systems Biology, National Taiwan University, Taipei City, Taiwan
| | - Kelly V. Ruggles
- Institute of Systems Genetics, New York University Grossman School of Medicine, New York, NY
- Division of Precision Medicine, Department of Medicine, New York University Grossman School of Medicine, New York, NY
| | - Kamal M. Khanna
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
- Perlmutter Cancer Center, New York University Grossman School of Medicine, New York, NY
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY
| | - P’ng Loke
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
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4
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Lacey KA, Serpas L, Makita S, Wang Y, Rashidfarrokhi A, Soni C, Gonzalez S, Moreira A, Torres VJ, Reizis B. Secreted mammalian DNases protect against systemic bacterial infection by digesting biofilms. J Exp Med 2023; 220:e20221086. [PMID: 36928522 PMCID: PMC10037111 DOI: 10.1084/jem.20221086] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 01/18/2023] [Accepted: 03/01/2023] [Indexed: 03/18/2023] Open
Abstract
Extracellular DNase DNASE1L3 maintains tolerance to self-DNA in humans and mice, whereas the role of its homolog DNASE1 remains controversial, and the overall function of secreted DNases in immunity is unclear. We report that deletion of murine DNASE1 neither caused autoreactivity in isolation nor exacerbated lupus-like disease in DNASE1L3-deficient mice. However, combined deficiency of DNASE1 and DNASE1L3 rendered mice susceptible to bloodstream infection with Staphylococcus aureus. DNASE1/DNASE1L3 double-deficient mice mounted a normal innate response to S. aureus and did not accumulate neutrophil extracellular traps (NETs). However, their kidneys manifested severe pathology, increased bacterial burden, and biofilm-like bacterial lesions that contained bacterial DNA and excluded neutrophils. Furthermore, systemic administration of recombinant DNASE1 protein during S. aureus infection rescued the mortality of DNase-deficient mice and ameliorated the disease in wild-type mice. Thus, DNASE1 and DNASE1L3 jointly facilitate the control of bacterial infection by digesting extracellular microbial DNA in biofilms, suggesting the original evolutionary function of secreted DNases as antimicrobial agents.
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Affiliation(s)
- Keenan A. Lacey
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Lee Serpas
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Sohei Makita
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Yueyang Wang
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Ali Rashidfarrokhi
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Chetna Soni
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Sandra Gonzalez
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Andre Moreira
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY, USA
| | - Boris Reizis
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, USA
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5
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Buckley PT, Chan R, Fernandez J, Luo J, Lacey KA, DuMont AL, O'Malley A, Brezski RJ, Zheng S, Malia T, Whitaker B, Zwolak A, Payne A, Clark D, Sigg M, Lacy ER, Kornilova A, Kwok D, McCarthy S, Wu B, Morrow B, Nemeth-Seay J, Petley T, Wu S, Strohl WR, Lynch AS, Torres VJ. Multivalent human antibody-centyrin fusion protein to prevent and treat Staphylococcus aureus infections. Cell Host Microbe 2023; 31:751-765.e11. [PMID: 37098341 DOI: 10.1016/j.chom.2023.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 02/12/2023] [Accepted: 04/03/2023] [Indexed: 04/27/2023]
Abstract
Treating and preventing infections by antimicrobial-resistant bacterial pathogens is a worldwide problem. Pathogens such as Staphylococcus aureus produce an array of virulence determinants, making it difficult to identify single targets for the development of vaccines or monoclonal therapies. We described a human-derived anti-S. aureus monoclonal antibody (mAb)-centyrin fusion protein ("mAbtyrin") that simultaneously targets multiple bacterial adhesins, resists proteolysis by bacterial protease GluV8, avoids Fc engagement by S. aureus IgG-binding proteins SpA and Sbi, and neutralizes pore-forming leukocidins via fusion with anti-toxin centyrins, while maintaining Fc- and complement-mediated functions. Compared with the parental mAb, mAbtyrin protected human phagocytes and boosted phagocyte-mediated killing. The mAbtyrin also reduced pathology, reduced bacterial burden, and protected from different types of infections in preclinical animal models. Finally, mAbtyrin synergized with vancomycin, enhancing pathogen clearance in an animal model of bacteremia. Altogether, these data establish the potential of multivalent mAbs for treating and preventing S. aureus diseases.
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Affiliation(s)
- Peter T Buckley
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA.
| | - Rita Chan
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Jeffrey Fernandez
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Jinquan Luo
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Keenan A Lacey
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Ashley L DuMont
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Aidan O'Malley
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Randall J Brezski
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Songmao Zheng
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Thomas Malia
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Brian Whitaker
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Adam Zwolak
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Angela Payne
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Desmond Clark
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Martin Sigg
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Eilyn R Lacy
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Anna Kornilova
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Debra Kwok
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Steve McCarthy
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Bingyuan Wu
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Brian Morrow
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | | | - Ted Petley
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Sam Wu
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - William R Strohl
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | | | - Victor J Torres
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA; Antimicrobial-Resistant Pathogens Program, New York University Langone Health, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA.
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6
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Loredan DG, Devlin JC, Lacey KA, Howard N, Chen Z, Zwack EE, Lin JD, Ruggles KV, Khanna KM, Torres VJ, Loke PN. Single-cell analysis of CX3CR1 + cells reveal a pathogenic role for BIRC5 + myeloid proliferating cells driven by Staphylococcus aureus leukotoxins. bioRxiv 2023:2023.02.27.529760. [PMID: 36909517 PMCID: PMC10002671 DOI: 10.1101/2023.02.27.529760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Our previous studies identified a population of stem cell-like proliferating myeloid cells within inflamed tissues that could serve as a reservoir for tissue macrophages to adopt different activation states depending on the microenvironment. By lineage tracing cells derived from CX3CR1 + precursors in mice during infection and profiling by scRNA-seq, here we identify a cluster of BIRC5 + myeloid cells that expanded in the liver during either chronic infection with the parasite Schistosoma mansoni or the bacterial pathogen Staphylococcus aureus . In the absence of tissue damaging toxins, S. aureus infection does not elicit these BIRC5 + cells. Moreover, deletion of BIRC5 from CX3CR1 expressing cells results in improved survival during S. aureus infection. Hence, the combination of scRNA-Seq and genetic fate mapping CX3CR1 + cells revealed a toxin dependent pathogenic role for BIRC5 in myeloid cells during S. aureus infection.
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7
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Haag AF, Liljeroos L, Donato P, Pozzi C, Brignoli T, Bottomley MJ, Bagnoli F, Delany I. In Vivo Gene Expression Profiling of Staphylococcus aureus during Infection Informs Design of Stemless Leukocidins LukE and -D as Detoxified Vaccine Candidates. Microbiol Spectr 2023; 11:e0257422. [PMID: 36688711 PMCID: PMC9927290 DOI: 10.1128/spectrum.02574-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 01/02/2023] [Indexed: 01/24/2023] Open
Abstract
Staphylococcus aureus is a clinically important bacterial pathogen that has become resistant to treatment with most routinely used antibiotics. Alternative strategies, such as vaccination and phage therapy, are therefore actively being investigated to prevent or combat staphylococcal infections. Vaccination requires that vaccine targets are expressed at sufficient quantities during infection so that they can be targeted by the host's immune system. While our knowledge of in vitro expression levels of putative vaccine candidates is comprehensive, crucial in vivo expression data are scarce and promising vaccine candidates during in vitro assessment often prove ineffective in preventing S. aureus infection. Here, we show how a newly developed high-throughput quantitative reverse transcription-PCR (qRT-PCR) assay monitoring the expression of 84 staphylococcal genes encoding mostly virulence factors can inform the selection and design of effective vaccine candidates against staphylococcal infections. We show that this assay can accurately quantify mRNA expression levels of these genes in several host organs relying only on very limited amounts of bacterial mRNA in each sample. We selected two highly expressed genes, lukE and lukD, encoding pore-forming leukotoxins, to inform the design of detoxified recombinant proteins and showed that immunization with recombinant genetically detoxified LukED antigens conferred protection against staphylococcal skin infection in mice. Consequently, knowledge of in vivo-expressed virulence determinants can be successfully deployed to identify and select promising candidates for optimized design of effective vaccine antigens against S. aureus. Notably, this approach should be broadly applicable to numerous other pathogens. IMPORTANCE Vaccination is an attractive strategy for preventing bacterial infections in an age of increased antimicrobial resistance. However, vaccine development frequently suffers significant setbacks when candidate antigens that show promising results in in vitro experimentation fail to protect from disease. An alluring strategy is to focus resources on developing bacterial virulence factors that are expressed during disease establishment or maintenance and are critical for bacterial in-host survival as vaccine targets. While expression profiles of many virulence factors have been characterized in detail in vitro, our knowledge of their in vivo expression profiles is still scarce. Here, using a high-throughput qRT-PCR approach, we identified two highly expressed leukotoxins in a murine infection model and showed that genetically detoxified derivatives of these elicited a protective immune response in a murine skin infection model. Therefore, in vivo gene expression can inform the selection of promising candidates for the design of effective vaccine antigens.
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Affiliation(s)
- Andreas F. Haag
- GSK, Siena, Italy
- School of Medicine, University of St. Andrews, St. Andrews, United Kingdom
| | | | | | | | - Tarcisio Brignoli
- GSK, Siena, Italy
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
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8
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Zwack EE, Chen Z, Devlin JC, Li Z, Zheng X, Weinstock A, Lacey KA, Fisher EA, Fenyö D, Ruggles KV, Loke P, Torres VJ. Staphylococcus aureus induces a muted host response in human blood that blunts the recruitment of neutrophils. Proc Natl Acad Sci U S A 2022; 119:e2123017119. [PMID: 35881802 DOI: 10.1073/pnas.2123017119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen and chief among bloodstream-infecting bacteria. S. aureus produces an array of human-specific virulence factors that may contribute to immune suppression. Here, we defined the response of primary human phagocytes following infection with S. aureus using RNA-sequencing (RNA-Seq). We found that the overall transcriptional response to S. aureus was weak both in the number of genes and in the magnitude of response. Using an ex vivo bacteremia model with fresh human blood, we uncovered that infection with S. aureus resulted in the down-regulation of genes related to innate immune response and cytokine and chemokine signaling. This muted transcriptional response was conserved across diverse S. aureus clones but absent in blood exposed to heat-killed S. aureus or blood infected with the less virulent staphylococcal species Staphylococcus epidermidis. Notably, this signature was also present in patients with S. aureus bacteremia. We identified the master regulator S. aureus exoprotein expression (SaeRS) and the SaeRS-regulated pore-forming toxins as key mediators of the transcriptional suppression. The S. aureus-mediated suppression of chemokine and cytokine transcription was reflected by circulating protein levels in the plasma. Wild-type S. aureus elicited a soluble milieu that was restrictive in the recruitment of human neutrophils compared with strains lacking saeRS. Thus, S. aureus blunts the inflammatory response resulting in impaired neutrophil recruitment, which could promote the survival of the pathogen during invasive infection.
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9
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Lacey KA, Gonzalez S, Yeung F, Putzel G, Podkowik M, Pironti A, Shopsin B, Cadwell K, Torres VJ. Microbiome-Independent Effects of Antibiotics in a Murine Model of Nosocomial Infections. mBio 2022;:e0124022. [PMID: 35612285 DOI: 10.1128/mbio.01240-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of hospital-acquired pneumonia. To better manage patients with MRSA pneumonia, we require a greater understanding of the host-pathogen interactions during infection. MRSA research focuses on highly virulent and cytotoxic strains, which demonstrate robust phenotypes in animal models of infection. However, nosocomial infections are often caused by hospital-acquired MRSA (HA-MRSA) isolates that exhibit low cytotoxicity and few or no phenotypes in mice, thereby confounding mechanistic studies of pathogenesis. Consequently, virulence pathways utilized by HA-MRSA in nosocomial pneumonia are largely unknown. Here, we report that conditioning mice with broad-spectrum antibiotics lowers the barrier to pneumonia, thereby transforming otherwise avirulent HA-MRSA isolates into lethal pathogens. HA-MRSA isolates are avirulent in gnotobiotic mice, mimicking results in conventional animals. Thus, the observed enhanced susceptibility to infection in antibiotic-treated mice is not due to depletion of the microbiota. More generally, we found that antibiotic conditioning leads to increased susceptibility to infection by diverse antimicrobial-resistant (AMR) pathogens of low virulence. Treatment with antibiotics leads to dehydration and malnutrition, suggesting a potential role for these clinically relevant and reducible hospital complications in susceptibility to pathogens. In sum, the model described here mitigates the impact of low virulence in immunocompetent mice, providing a convenient model to gain fundamental insight into the pathogenesis of nosocomial pathogens.
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10
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Tsai CM, Hajam IA, Caldera JR, Liu GY. Integrating complex host-pathogen immune environments into S. aureus vaccine studies. Cell Chem Biol 2022; 29:730-740. [PMID: 35594849 DOI: 10.1016/j.chembiol.2022.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/16/2022] [Accepted: 04/14/2022] [Indexed: 11/18/2022]
Abstract
Staphylococcus aureus (SA) is a leading cause of bacterial infection and antibiotic resistance globally. Therefore, development of an effective vaccine has been a major goal of the SA field for the past decades. With the wealth of understanding of pathogenesis, the failure of all SA vaccine trials has been a surprise. We argue that experimental SA vaccines have not worked because vaccines have been studied in naive laboratory animals, whereas clinical vaccine efficacy is tested in immune environments reprogrammed by SA. Here, we review the failed SA vaccines that have seemingly defied all principles of vaccinology. We describe major SA evasion strategies and suggest that they reshape the immune environment in a way that makes vaccines prone to failures. We propose that appropriate integration of concepts of host-pathogen interaction into vaccine study designs could lead to insight critical for the development of an effective SA vaccine.
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Affiliation(s)
- Chih-Ming Tsai
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Irshad A Hajam
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - J R Caldera
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - George Y Liu
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA; Division of Infectious Diseases, Rady Children's Hospital, San Diego, CA 92123, USA.
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11
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Zheng X, Ma SX, St John A, Torres VJ. The Major Autolysin Atl Regulates the Virulence of Staphylococcus aureus by Controlling the Sorting of LukAB. Infect Immun 2022;:e0005622. [PMID: 35258336 DOI: 10.1128/iai.00056-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Infections caused by the Gram-positive bacterium Staphylococcus aureus remain a significant health threat globally. The production of bicomponent pore-forming leukocidins plays an important role in S. aureus pathogenesis. Transcriptionally, these toxins are primarily regulated by the Sae and Agr regulatory systems. However, the posttranslational regulation of these toxins is largely unexplored. In particular, one of the leukocidins, LukAB, has been shown to be both secreted into the extracellular milieu and associated with the bacterial cell envelope. Here, we report that a major cell wall hydrolase, autolysin (Atl), controls the sorting of LukAB from the cell envelope to the extracellular milieu, an effect independent of transcriptional regulation. By influencing the sorting of LukAB, Atl modulates S. aureus cytotoxicity toward primary human neutrophils. Mechanistically, we found that the reduction in peptidoglycan cleavage and increased LukAB secretion in the atl mutant can be reversed through the supplementation of exogenous mutanolysin. Altogether, our study revealed that the cell wall hydrolase activity of Atl and the cleavage of peptidoglycan play an important role in controlling the sorting of S. aureus toxins during secretion.
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12
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Li Z, Beesetty P, Gerges G, Kleinhenz M, Moore-Clingenpeel M, Yang C, Ahmed LB, Hensley J, Steele L, Chong AS, Montgomery CP. Impaired T lymphocyte responses during childhood Staphylococcus aureus infection. J Infect Dis 2021; 225:177-185. [PMID: 34145461 DOI: 10.1093/infdis/jiab326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/16/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Staphylococcus aureus infections are common throughout the lifespan, with recurrent infections occuring in nearly half of infected children. There is no licensed vaccine, underscoring the need to better understand how S. aureus evades protective immunity. Despite much study, the relative contributions of antibodies and T cells to protection against S. aureus infections in humans are not fully understood. METHODS We prospectively quantified S. aureus-specific antibody levels by ELISA and T cell responses by ELISpot in S. aureus-infected and healthy children. RESULTS S. aureus-specific antibody levels and T cell responses increased with age in healthy children, suggesting a coordinated development of anti-staphylococcal immunity. Antibody levels against leukotoxin E (LukE) and Panton-Valentine leukocidin (LukS-PV), but not α-hemolysin (Hla), were higher in younger infected children, compared with healthy children; these differences disappeared in older children. We observed a striking impairment of global and S. aureus-specific T cell function in children with invasive and non-invasive infection, suggesting that S. aureus-specific immune responses are dysregulated during childhood infection regardless of the infection phenotype. CONCLUSIONS These findings identify a potential mechanism by which S. aureus infection actively evades adaptive immune responses, thereby preventing the development of protective immunty and maintaining susceptibility to recurrent infection.
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Affiliation(s)
- Zhaotao Li
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Pavani Beesetty
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - George Gerges
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Maureen Kleinhenz
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | | | - Ching Yang
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.,Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
| | - Luul B Ahmed
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Josey Hensley
- Division of Critical Care Medicine, Nationwide Children's Hospital, Columbus, OH, USA
| | - Lisa Steele
- Division of Critical Care Medicine, Nationwide Children's Hospital, Columbus, OH, USA
| | - Anita S Chong
- Department of Surgery, University of Chicago, Chicago, IL, USA
| | - Christopher P Montgomery
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.,Division of Critical Care Medicine, Nationwide Children's Hospital, Columbus, OH, USA.,Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, OH, USA
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13
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Fernandez J, Sanders H, Henn J, Wilson JM, Malone D, Buoninfante A, Willms M, Chan R, DuMont AL, McLahan C, Grubb K, Romanello A, van den Dobbelsteen G, Torres VJ, Poolman JT. Vaccination with Detoxified Leukocidin AB Reduces Bacterial Load in a Staphylococcus aureus Minipig Deep Surgical Wound Infection Model. J Infect Dis 2021; 225:1460-1470. [PMID: 33895843 PMCID: PMC9016470 DOI: 10.1093/infdis/jiab219] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 04/19/2021] [Indexed: 12/15/2022] Open
Abstract
Vaccines against Staphylococcus aureus have eluded researchers for >3 decades while the burden of staphylococcal diseases has increased. Early vaccine attempts mainly used rodents to characterize preclinical efficacy, and all subsequently failed in human clinical efficacy trials. More recently, leukocidin AB (LukAB) has gained interest as a vaccine antigen. We developed a minipig deep surgical wound infection model offering 3 independent efficacy readouts: bacterial load at the superficial and at the deep-seated surgical site, and dissemination of bacteria. Due to similarities with humans, minipigs are an attractive option to study novel vaccine candidates. With this model, we characterized the efficacy of a LukAB toxoid as vaccine candidate. Compared to control animals, a 3-log reduction of bacteria at the deep-seated surgical site was observed in LukAB-treated minipigs and dissemination of bacteria was dramatically reduced. Therefore, LukAB toxoids may be a useful addition to S. aureus vaccines and warrant further study.
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Affiliation(s)
| | - H Sanders
- Janssen Vaccines & Prevention B.V., Leiden, The Netherlands
| | - J Henn
- Bacterial Vaccines, Spring House, PA, USA
| | | | - D Malone
- Bacterial Vaccines, Spring House, PA, USA
| | - A Buoninfante
- Janssen Vaccines & Prevention B.V., Leiden, The Netherlands
| | - M Willms
- Bacterial Vaccines, Spring House, PA, USA
| | - R Chan
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - A L DuMont
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - C McLahan
- In Vivo Sciences, Spring House, PA, USA
| | - K Grubb
- Bacterial Vaccines, Spring House, PA, USA
| | | | | | - V J Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - J T Poolman
- Janssen Vaccines & Prevention B.V., Leiden, The Netherlands
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14
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de Morais SD, Kak G, Menousek JP, Kielian T. Immunopathogenesis of Craniotomy Infection and Niche-Specific Immune Responses to Biofilm. Front Immunol 2021; 12:625467. [PMID: 33708216 PMCID: PMC7940520 DOI: 10.3389/fimmu.2021.625467] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/05/2021] [Indexed: 02/06/2023] Open
Abstract
Bacterial infections in the central nervous system (CNS) can be life threatening and often impair neurological function. Biofilm infection is a complication following craniotomy, a neurosurgical procedure that involves the removal and replacement of a skull fragment (bone flap) to access the brain for surgical intervention. The incidence of infection following craniotomy ranges from 1% to 3% with approximately half caused by Staphylococcus aureus (S. aureus). These infections present a significant therapeutic challenge due to the antibiotic tolerance of biofilm and unique immune properties of the CNS. Previous studies have revealed a critical role for innate immune responses during S. aureus craniotomy infection. Experiments using knockout mouse models have highlighted the importance of the pattern recognition receptor Toll-like receptor 2 (TLR2) and its adaptor protein MyD88 for preventing S. aureus outgrowth during craniotomy biofilm infection. However, neither molecule affected bacterial burden in a mouse model of S. aureus brain abscess highlighting the distinctions between immune regulation of biofilm vs. planktonic infection in the CNS. Furthermore, the immune responses elicited during S. aureus craniotomy infection are distinct from biofilm infection in the periphery, emphasizing the critical role for niche-specific factors in dictating S. aureus biofilm-leukocyte crosstalk. In this review, we discuss the current knowledge concerning innate immunity to S. aureus craniotomy biofilm infection, compare this to S. aureus biofilm infection in the periphery, and discuss the importance of anatomical location in dictating how biofilm influences inflammatory responses and its impact on bacterial clearance.
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Affiliation(s)
- Sharon Db de Morais
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Gunjan Kak
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Joseph P Menousek
- Department of Neurosurgery, University of Nebraska Medical Center, Omaha, NE, United States
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
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15
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Ford CA, Hurford IM, Cassat JE. Antivirulence Strategies for the Treatment of Staphylococcus aureus Infections: A Mini Review. Front Microbiol 2021; 11:632706. [PMID: 33519793 PMCID: PMC7840885 DOI: 10.3389/fmicb.2020.632706] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
Staphylococcus aureus is a Gram-positive bacterium capable of infecting nearly all host tissues, causing severe morbidity and mortality. Widespread antimicrobial resistance has emerged among S. aureus clinical isolates, which are now the most frequent causes of nosocomial infection among drug-resistant pathogens. S. aureus produces an array of virulence factors that enhance in vivo fitness by liberating nutrients from the host or evading host immune responses. Staphylococcal virulence factors have been identified as viable therapeutic targets for treatment, as they contribute to disease pathogenesis, tissue injury, and treatment failure. Antivirulence strategies, or treatments targeting virulence without direct toxicity to the inciting pathogen, show promise as an adjunctive therapy to traditional antimicrobials. This Mini Review examines recent research on S. aureus antivirulence strategies, with an emphasis on translational studies. While many different virulence factors have been investigated as therapeutic targets, this review focuses on strategies targeting three virulence categories: pore-forming toxins, immune evasion mechanisms, and the S. aureus quorum sensing system. These major areas of S. aureus antivirulence research demonstrate broad principles that may apply to other human pathogens. Finally, challenges of antivirulence research are outlined including the potential for resistance, the need to investigate multiple infection models, and the importance of studying antivirulence in conjunction with traditional antimicrobial treatments.
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Affiliation(s)
- Caleb A. Ford
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
| | - Ian M. Hurford
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - James E. Cassat
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, TN, United States
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16
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Vasquez MT, Lubkin A, Reyes-Robles T, Day CJ, Lacey KA, Jennings MP, Torres VJ. Identification of a domain critical for Staphylococcus aureus LukED receptor targeting and lysis of erythrocytes. J Biol Chem 2020; 295:17241-17250. [PMID: 33051210 PMCID: PMC7863875 DOI: 10.1074/jbc.ra120.015757] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/07/2020] [Indexed: 12/14/2022] Open
Abstract
Leukocidin ED (LukED) is a pore-forming toxin produced by Staphylococcus aureus, which lyses host cells and promotes virulence of the bacteria. LukED enables S. aureus to acquire iron by lysing erythrocytes, which depends on targeting the host receptor Duffy antigen receptor for chemokines (DARC). The toxin also targets DARC on the endothelium, contributing to the lethality observed during bloodstream infection in mice. LukED is comprised of two monomers: LukE and LukD. LukE binds to DARC and facilitates hemolysis, but the closely related Panton-Valentine leukocidin S (LukS-PV) does not bind to DARC and is not hemolytic. The interaction of LukE with DARC and the role this plays in hemolysis are incompletely characterized. To determine the domain(s) of LukE that are critical for DARC binding, we studied the hemolytic function of LukE-LukS-PV chimeras, in which areas of sequence divergence (divergence regions, or DRs) were swapped between the toxins. We found that two regions of LukE's rim domain contribute to hemolysis, namely residues 57-75 (DR1) and residues 182-196 (DR4). Interestingly, LukE DR1 is sufficient to render LukS-PV capable of DARC binding and hemolysis. Further, LukE, by binding DARC through DR1, promotes the recruitment of LukD to erythrocytes, likely by facilitating LukED oligomer formation. Finally, we show that LukE targets murine Darc through DR1 in vivo to cause host lethality. These findings expand our biochemical understanding of the LukE-DARC interaction and the role that this toxin-receptor pair plays in S. aureus pathophysiology.
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Affiliation(s)
- Marilyn T Vasquez
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Ashira Lubkin
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Tamara Reyes-Robles
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Christopher J Day
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Keenan A Lacey
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Victor J Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA.
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17
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Poddighe D, Vangelista L. Staphylococcus aureus Infection and Persistence in Chronic Rhinosinusitis: Focus on Leukocidin ED. Toxins (Basel) 2020; 12:E678. [PMID: 33126405 DOI: 10.3390/toxins12110678] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022] Open
Abstract
Chronic rhinosinusitis (CRS) is thought to be a multifactorial disease that includes a direct involvement of bacteria that trigger inflammation and contribute to CRS pathogenesis. Staphylococcus aureus infection and persistence is associated with chronic rhinosinusitis (CRS), and it may be particularly relevant in the form with nasal polyps (CRSwNP). The large array of exotoxins deployed by S. aureus is instrumental for the bacterium to warrant its infection and dissemination in different human body districts. Here, we analyze the common Th2 environment in CRSwNP and prospect a possible dynamic role played by S. aureus leukocidins in promoting this chronic inflammation, considering leukocidin ED (LukED) as a strong prototype candidate worth of therapeutic investigation. CCR5 is an essential target for LukED to exert its cytotoxicity towards T cells, macrophages and dendritic cells. Therefore, CCR5 blockade might be an interesting therapeutic option for CRS and, more specifically, persistent and relapsing CRSwNP. In this perspective, the arsenal of CCR5 antagonists being developed to inhibit HIV-1 entry (CCR5 being the major HIV-1 co-receptor) could be easily repurposed for CRS therapeutic investigation. Finally, direct targeting of LukED by neutralizing antibodies could represent an important additional solution to S. aureus infection.
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18
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Mrochen DM, Fernandes de Oliveira LM, Raafat D, Holtfreter S. Staphylococcus aureus Host Tropism and Its Implications for Murine Infection Models. Int J Mol Sci 2020; 21:E7061. [PMID: 32992784 PMCID: PMC7582387 DOI: 10.3390/ijms21197061] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 09/22/2020] [Accepted: 09/22/2020] [Indexed: 12/11/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is a pathobiont of humans as well as a multitude of animal species. The high prevalence of multi-resistant and more virulent strains of S. aureus necessitates the development of new prevention and treatment strategies for S. aureus infection. Major advances towards understanding the pathogenesis of S. aureus diseases have been made using conventional mouse models, i.e., by infecting naïve laboratory mice with human-adapted S.aureus strains. However, the failure to transfer certain results obtained in these murine systems to humans highlights the limitations of such models. Indeed, numerous S. aureus vaccine candidates showed promising results in conventional mouse models but failed to offer protection in human clinical trials. These limitations arise not only from the widely discussed physiological differences between mice and humans, but also from the lack of attention that is paid to the specific interactions of S. aureus with its respective host. For instance, animal-derived S. aureus lineages show a high degree of host tropism and carry a repertoire of host-specific virulence and immune evasion factors. Mouse-adapted S.aureus strains, humanized mice, and microbiome-optimized mice are promising approaches to overcome these limitations and could improve transferability of animal experiments to human trials in the future.
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Affiliation(s)
- Daniel M. Mrochen
- Department of Immunology, Institute of Immunology and Transfusion Medicine, University Medicine Greifswald, Ferdinand-Sauerbruch-Strasse DZ 7, 17475 Greifswald, Germany; (L.M.F.d.O.); (D.R.); (S.H.)
| | - Liliane M. Fernandes de Oliveira
- Department of Immunology, Institute of Immunology and Transfusion Medicine, University Medicine Greifswald, Ferdinand-Sauerbruch-Strasse DZ 7, 17475 Greifswald, Germany; (L.M.F.d.O.); (D.R.); (S.H.)
| | - Dina Raafat
- Department of Immunology, Institute of Immunology and Transfusion Medicine, University Medicine Greifswald, Ferdinand-Sauerbruch-Strasse DZ 7, 17475 Greifswald, Germany; (L.M.F.d.O.); (D.R.); (S.H.)
- Department of Microbiology and Immunology, Faculty of Pharmacy, Alexandria University, 21521 Alexandria, Egypt
| | - Silva Holtfreter
- Department of Immunology, Institute of Immunology and Transfusion Medicine, University Medicine Greifswald, Ferdinand-Sauerbruch-Strasse DZ 7, 17475 Greifswald, Germany; (L.M.F.d.O.); (D.R.); (S.H.)
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