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Heston SM, Hurst JH, Kelly MS. Understanding the influence of the microbiome on childhood infections. Expert Rev Anti Infect Ther 2024:1-17. [PMID: 38605646 DOI: 10.1080/14787210.2024.2340664] [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: 12/29/2023] [Accepted: 04/04/2024] [Indexed: 04/13/2024]
Abstract
INTRODUCTION The microbiome is known to have a substantial impact on human health and disease. However, the impacts of the microbiome on immune system development, susceptibility to infectious diseases, and vaccine-elicited immune responses are emerging areas of interest. AREAS COVERED In this review, we provide an overview of development of the microbiome during childhood. We highlight available data suggesting that the microbiome is critical to maturation of the immune system and modifies susceptibility to a variety of infections during childhood and adolescence, including respiratory tract infections, Clostridioides difficile infection, and sexually transmitted infections. We discuss currently available and investigational therapeutics that have the potential to modify the microbiome to prevent or treat infections among children. Finally, we review the accumulating evidence that the gut microbiome influences vaccine-elicited immune responses among children. EXPERT OPINION Recent advances in sequencing technologies have led to an explosion of studies associating the human microbiome with the risk and severity of infectious diseases. As our knowledge of the extent to which the microbiome influences childhood infections continues to grow, microbiome-based diagnostics and therapeutics will increasingly be incorporated into clinical practice to improve the prevention, diagnosis, and treatment of infectious diseases among children.
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Affiliation(s)
- Sarah M Heston
- Pediatrics, Duke University School of Medicine, Durham, NC, UK
| | - Jillian H Hurst
- Pediatrics, Duke University School of Medicine, Durham, NC, UK
| | - Matthew S Kelly
- Pediatrics, Duke University School of Medicine, Durham, NC, UK
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Stubbendieck RM, Hurst JH, Kelly MS. Dolosigranulum pigrum: A promising nasal probiotic candidate. PLoS Pathog 2024; 20:e1011955. [PMID: 38300905 PMCID: PMC10833571 DOI: 10.1371/journal.ppat.1011955] [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: 02/03/2024] Open
Affiliation(s)
- Reed M. Stubbendieck
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Jillian H. Hurst
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, United States of America
- Children’s Health and Discovery Institute, Department of Pediatrics, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Matthew S. Kelly
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, United States of America
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Drigot ZG, Clark SE. Insights into the role of the respiratory tract microbiome in defense against bacterial pneumonia. Curr Opin Microbiol 2024; 77:102428. [PMID: 38277901 PMCID: PMC10922932 DOI: 10.1016/j.mib.2024.102428] [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: 09/26/2023] [Revised: 01/03/2024] [Accepted: 01/05/2024] [Indexed: 01/28/2024]
Abstract
The respiratory tract microbiome (RTM) is a microbial ecosystem inhabiting different niches throughout the airway. A critical role for the RTM in dictating lung infection outcomes is underlined by recent efforts to identify community members benefiting respiratory tract health. Obligate anaerobes common in the oropharynx and lung such as Prevotella and Veillonella are associated with improved pneumonia outcomes and activate several immune defense pathways in the lower airway. Colonizers of the nasal cavity, including Corynebacterium and Dolosigranulum, directly impact the growth and virulence of lung pathogens, aligning with robust clinical correlations between their upper airway abundance and reduced respiratory tract infection risk. Here, we highlight recent work identifying respiratory tract bacteria that promote airway health and resilience against disease, with a focus on lung infections and the underlying mechanisms driving RTM-protective benefits.
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Affiliation(s)
- Zoe G Drigot
- University of Colorado School of Medicine, Department of Otolaryngology, Aurora, CO 80045, USA
| | - Sarah E Clark
- University of Colorado School of Medicine, Department of Otolaryngology, Aurora, CO 80045, USA.
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Liu X, Tong X, Zou L, Ju Y, Liu M, Han M, Lu H, Yang H, Wang J, Zong Y, Liu W, Xu X, Jin X, Xiao L, Jia H, Guo R, Zhang T. A genome-wide association study reveals the relationship between human genetic variation and the nasal microbiome. Commun Biol 2024; 7:139. [PMID: 38291185 PMCID: PMC10828421 DOI: 10.1038/s42003-024-05822-5] [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: 06/27/2023] [Accepted: 01/15/2024] [Indexed: 02/01/2024] Open
Abstract
The nasal cavity harbors diverse microbiota that contributes to human health and respiratory diseases. However, whether and to what extent the host genome shapes the nasal microbiome remains largely unknown. Here, by dissecting the human genome and nasal metagenome data from 1401 healthy individuals, we demonstrated that the top three host genetic principal components strongly correlated with the nasal microbiota diversity and composition. The genetic association analyses identified 63 genome-wide significant loci affecting the nasal microbial taxa and functions, of which 2 loci reached study-wide significance (p < 1.7 × 10-10): rs73268759 within CAMK2A associated with genus Actinomyces and family Actinomycetaceae; and rs35211877 near POM121L12 with Gemella asaccharolytica. In addition to respiratory-related diseases, the associated loci are mainly implicated in cardiometabolic or neuropsychiatric diseases. Functional analysis showed the associated genes were most significantly expressed in the nasal airway epithelium tissue and enriched in the calcium signaling and hippo signaling pathway. Further observational correlation and Mendelian randomization analyses consistently suggested the causal effects of Serratia grimesii and Yokenella regensburgei on cardiometabolic biomarkers (cystine, glutamic acid, and creatine). This study suggested that the host genome plays an important role in shaping the nasal microbiome.
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Affiliation(s)
- Xiaomin Liu
- BGI Research, Shenzhen, 518083, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xin Tong
- BGI Research, Shenzhen, 518083, China
| | | | - Yanmei Ju
- BGI Research, Shenzhen, 518083, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | | | - Mo Han
- BGI Research, Shenzhen, 518083, China
| | - Haorong Lu
- China National Genebank, BGI-Shenzhen, Shenzhen, 518120, China
| | - Huanming Yang
- BGI Research, Shenzhen, 518083, China
- James D. Watson Institute of Genome Sciences, Hangzhou, 310058, China
| | - Jian Wang
- BGI Research, Shenzhen, 518083, China
- James D. Watson Institute of Genome Sciences, Hangzhou, 310058, China
| | - Yang Zong
- BGI Research, Shenzhen, 518083, China
| | | | - Xun Xu
- BGI Research, Shenzhen, 518083, China
| | - Xin Jin
- BGI Research, Shenzhen, 518083, China
| | - Liang Xiao
- BGI Research, Shenzhen, 518083, China
- Shenzhen Engineering Laboratory of Detection and Intervention of Human Intestinal Microbiome, BGI-Shenzhen, Shenzhen, 518083, China
| | - Huijue Jia
- Greater Bay Area Institute of Precision Medicine, Guangzhou, Guangdong, China.
- School of Life Sciences, Fudan University, Shanghai, China.
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Hurst JH, Heston SM, Kelly MS. Host microbiome-pathogen interactions in pediatric infections. Curr Opin Infect Dis 2023; 36:399-404. [PMID: 37462955 PMCID: PMC10529085 DOI: 10.1097/qco.0000000000000949] [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] [Indexed: 09/12/2023]
Abstract
PURPOSE OF REVIEW In this review, we discuss recent research that has furthered our understanding of microbiome development during childhood, the role of the microbiome in infections during this life stage, and emerging opportunities for microbiome-based therapies for infection prevention or treatment in children. RECENT FINDINGS The microbiome is highly dynamic during childhood and shaped by a variety of host and environmental factors. In turn, the microbiome influences risk and severity of a broad range of infections during childhood, with recent studies highlighting potential roles in respiratory, gastrointestinal, and systemic infections. The microbiome exerts this influence through both direct interactions with potential pathogens and indirectly through modulation of host immune responses. The elucidation of some of these mechanisms by recent studies and the development of effective microbiome-based therapies for adults with recurrent Clostridioides difficile infection highlight the enormous promise that targeting the microbiome has for reducing the burden of infectious diseases during childhood. SUMMARY The microbiome has emerged as a key modifier of infection susceptibility and severity among children. Further research is needed to define the roles of microbes other than bacteria and to elucidate the mechanisms underlying microbiome-host and microbiome-pathogen interactions of importance to infectious diseases in children.
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Affiliation(s)
- Jillian H. Hurst
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC
- Duke Microbiome Center, Duke University School of Medicine, Durham, NC
| | - Sarah M. Heston
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC
- Duke Microbiome Center, Duke University School of Medicine, Durham, NC
| | - Matthew S. Kelly
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC
- Duke Microbiome Center, Duke University School of Medicine, Durham, NC
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Hurst JH, Kelly MS. Leveraging the human microbiota to target bacterial respiratory pathogens: new paths toward an expanded antimicrobial armamentarium. mBio 2023; 14:e0085423. [PMID: 37338299 PMCID: PMC10470731 DOI: 10.1128/mbio.00854-23] [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] [Indexed: 06/21/2023] Open
Abstract
Acute respiratory infections are the most frequent infections across the lifespan and are the leading infectious cause of death among children globally. Bacterial respiratory infections are routinely treated with antibiotics, nearly all of which are derived from microbial natural products. Unfortunately, antibiotic-resistant bacteria are an increasingly frequent cause of respiratory infections, and there are few new antibiotics in development that target these pathogens. In the article by Stubbendieck et al., the authors identified Rothia species that demonstrate in vitro and ex vivo growth inhibition of the respiratory pathobiont Moraxella catarrhalis. The authors present experiments suggesting that this activity is mediated at least in part through the secretion of a novel peptidoglycan endopeptidase that targets the M. catarrhalis cell wall. In this commentary, we discuss these findings in the context of the urgent threat of antimicrobial resistance and highlight the promise of the human respiratory microbiota as a source of novel biotherapeutics.
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Affiliation(s)
- Jillian H. Hurst
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA
- Duke Microbiome Center, Duke University School of Medicine, Durham, North Carolina, USA
| | - Matthew S. Kelly
- Department of Pediatrics, Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA
- Duke Microbiome Center, Duke University School of Medicine, Durham, North Carolina, USA
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Tran TH, Roberts AQ, Escapa IF, Gao W, Segre JA, Kong HH, Conlan S, Kelly MS, Lemon KP. Metabolic capabilities are highly conserved among human nasal-associated Corynebacterium species in pangenomic analyses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.05.543719. [PMID: 37333201 PMCID: PMC10274666 DOI: 10.1101/2023.06.05.543719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Corynebacterium species are globally ubiquitous in human nasal microbiota across the lifespan. Moreover, nasal microbiota profiles typified by higher relative abundances of Corynebacterium are often positively associated with health. Among the most common human nasal Corynebacterium species are C. propinquum, C. pseudodiphtheriticum, C. accolens, and C. tuberculostearicum. Based on the prevalence of these species, at least two likely coexist in the nasal microbiota of 82% of adults. To gain insight into the functions of these four species, we identified genomic, phylogenomic, and pangenomic properties and estimated the functional protein repertoire and metabolic capabilities of 87 distinct human nasal Corynebacterium strain genomes: 31 from Botswana and 56 from the U.S. C. pseudodiphtheriticum had geographically distinct clades consistent with localized strain circulation, whereas some strains from the other species had wide geographic distribution across Africa and North America. All four species had similar genomic and pangenomic structures. Gene clusters assigned to all COG metabolic categories were overrepresented in the persistent (core) compared to the accessory genome of each species indicating limited strain-level variability in metabolic capacity. Moreover, core metabolic capabilities were highly conserved among the four species indicating limited species-level metabolic variation. Strikingly, strains in the U.S. clade of C. pseudodiphtheriticum lacked genes for assimilatory sulfate reduction present in the Botswanan clade and in the other studied species, indicating a recent, geographically related loss of assimilatory sulfate reduction. Overall, the minimal species and strain variability in metabolic capacity implies coexisting strains might have limited ability to occupy distinct metabolic niches.
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Affiliation(s)
- Tommy H. Tran
- Alkek Center for Metagenomics & Microbiome Research, Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Ari Q. Roberts
- Alkek Center for Metagenomics & Microbiome Research, Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Isabel F. Escapa
- Alkek Center for Metagenomics & Microbiome Research, Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Wei Gao
- The Forsyth Institute (Microbiology), Cambridge, MA, USA
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Julie A. Segre
- Microbial Genomics Section, Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Heidi H. Kong
- Dermatology Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sean Conlan
- Microbial Genomics Section, Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Matthew S. Kelly
- Division of Pediatric Infectious Diseases, Duke University School of Medicine, Durham, NC, USA
| | - Katherine P. Lemon
- Alkek Center for Metagenomics & Microbiome Research, Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, USA
- Division of Infectious Diseases, Texas Children’s Hospital, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
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Treerat P, Anderson D, Giacaman RA, Merritt J, Kreth J. Glycerol metabolism supports oral commensal interactions. THE ISME JOURNAL 2023:10.1038/s41396-023-01426-9. [PMID: 37169870 DOI: 10.1038/s41396-023-01426-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 04/19/2023] [Accepted: 04/27/2023] [Indexed: 05/13/2023]
Abstract
During oral biofilm development, interspecies interactions drive species distribution and biofilm architecture. To understand what molecular mechanisms determine these interactions, we used information gained from recent biogeographical investigations demonstrating an association of corynebacteria with streptococci. We previously reported that Streptococcus sanguinis and Corynebacterium durum have a close relationship through the production of membrane vesicle and fatty acids leading to S. sanguinis chain elongation and overall increased fitness supporting their commensal state. Here we present the molecular mechanisms of this interspecies interaction. Coculture experiments for transcriptomic analysis identified several differentially expressed genes in S. sanguinis. Due to its connection to fatty acid synthesis, we focused on the glycerol-operon. We further explored the differentially expressed type IV pili genes due to their connection to motility and biofilm adhesion. Gene inactivation of the glycerol kinase glpK had a profound impact on the ability of S. sanguinis to metabolize C. durum secreted glycerol and impaired chain elongation important for their interaction. Investigations on the effect of type IV pili revealed a reduction of S. sanguinis twitching motility in the presence of C. durum, which was caused by a decrease in type IV pili abundance on the surface of S. sanguinis as determined by SEM. In conclusion, we identified that the ability to metabolize C. durum produced glycerol is crucial for the interaction of C. durum and S. sanguinis. Reduced twitching motility could lead to a closer interaction of both species, supporting niche development in the oral cavity and potentially shaping symbiotic health-associated biofilm communities.
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Affiliation(s)
- Puthayalai Treerat
- Department of Restorative Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA.
| | - David Anderson
- Department of Restorative Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA
| | - Rodrigo A Giacaman
- Cariology Unit, Department of Oral Rehabilitation, Faculty of Dentistry, University of Talca, Talca, Chile
| | - Justin Merritt
- Department of Restorative Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA
| | - Jens Kreth
- Department of Restorative Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA.
- Department of Molecular Microbiology and Immunology, School of Medicine, Oregon Health & Science University (OHSU), Portland, OR, 97239, USA.
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Odom-Mabey AR, Gill CJ, Pieciak R, Ismail A, Thea D, MacLeod WB, Johnson WE, Lapidot R. Characterization of longitudinal nasopharyngeal microbiome patterns in maternally HIV-exposed Zambian infants. Gates Open Res 2022. [DOI: 10.12688/gatesopenres.14041.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Previous studies of infants born to HIV-positive mothers have linked HIV exposure to poor outcomes from gastrointestinal and respiratory illnesses, and to overall increased mortality rates. The mechanism behind this is unknown, but it is possible that differences in the nasopharyngeal (NP) microbiome between HIV-unexposed and HIV-exposed infants could play a role in perpetuating some outcomes. Methods: We conducted a longitudinal analysis of 170 NP swabs of healthy HIV-exposed, uninfected (HEU; n=10) infants and their HIV(+) mothers and HIV-unexposed, uninfected (HUU; n=10) infants and their HIV(-) mothers. These swabs were identified from a sample library collected in Lusaka, Zambia between 2015 and 2016. Using 16S rRNA gene sequencing, we characterized the maturation of the microbiome over the first 14 weeks of life to determine what quantifiable differences exist between HEU and HUU infants, and what patterns are reflected in the mothers' NP microbiomes. Results: In both HEU and HUU infants, Staphylococcus and Corynebacterium began as primary colonizers of the NP microbiome but were in time replaced by Dolosigranulum, Streptococcus, Moraxella and Haemophilus. When studying differences between infants, the microbe Staphylococcus haemolyticus indicated a distinctive high association with HIV exposure at birth, even when accounting for the interaction between HIV exposure status and time of sampling. When comparing infants to their mothers with paired analyses, HEU infants’ NP microbiome composition was only slightly different from their HIV(+) mothers at birth or 14 weeks, including in their carriage of S. pneumoniae, H. influenzae, and S. haemolyticus. Conclusions: Our analyses indicate that the HEU infants in our study exhibit subtle differences in the NP microbial composition throughout the sampling interval. Given our results and the sampling limitations of our study, we believe that further research must be conducted in order to confidently understand the relationship between HIV exposure and infants’ NP microbiomes.
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Recurrent Acute Otitis Media Environmental Risk Factors: A Literature Review from the Microbiota Point of View. Appl Microbiol 2022. [DOI: 10.3390/applmicrobiol2030046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Acute otitis media (AOM) constitutes a multifactorial disease, as several host and environmental factors contribute to its occurrence. Prevention of AOM represents one of the most important goals in pediatrics, both in developing countries, in which complications, mortality, and deafness remain possible consequences of the disease, compared to in developed countries, in which this condition has an important burden in terms of medical, social, and economical implications. The strategies for AOM prevention are based on reducing the burden of risk factors, through the application of behavioral, environmental, and therapeutic interventions. The introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, providing novel insights into the pathogenesis of middle ear diseases through the identification of potential protective bacteria. The upper respiratory tract (URT) is a pivotal region in AOM pathogenesis, as it could act as a source of pathogens than of protective microorganisms for the middle ear (ME). Due to its direct connection with the external ambient, the URT is particularly exposed to the influence of environmental agents. The aim of this review was to evaluate AOM environmental risk factors and their impact on URT microbial communities, and to investigate AOM pathogenesis from the microbiota perspective.
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Horn KJ, Jaberi Vivar AC, Arenas V, Andani S, Janoff EN, Clark SE. Corynebacterium Species Inhibit Streptococcus pneumoniae Colonization and Infection of the Mouse Airway. Front Microbiol 2022; 12:804935. [PMID: 35082772 PMCID: PMC8784410 DOI: 10.3389/fmicb.2021.804935] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/03/2021] [Indexed: 12/21/2022] Open
Abstract
The stability and composition of the airway microbiome is an important determinant of respiratory health. Some airway bacteria are considered to be beneficial due to their potential to impede the acquisition and persistence of opportunistic bacterial pathogens such as Streptococcus pneumoniae. Among such organisms, the presence of Corynebacterium species correlates with reduced S. pneumoniae in both adults and children, in whom Corynebacterium abundance is predictive of S. pneumoniae infection risk. Previously, Corynebacterium accolens was shown to express a lipase which cleaves host lipids, resulting in the production of fatty acids that inhibit growth of S. pneumoniae in vitro. However, it was unclear whether this mechanism contributes to Corynebacterium-S. pneumoniae interactions in vivo. To address this question, we developed a mouse model for Corynebacterium colonization in which colonization with either C. accolens or another species, Corynebacterium amycolatum, significantly reduced S. pneumoniae acquisition in the upper airway and infection in the lung. Moreover, the lungs of co-infected mice had reduced pro-inflammatory cytokines and inflammatory myeloid cells, indicating resolution of infection-associated inflammation. The inhibitory effect of C. accolens on S. pneumoniae in vivo was mediated by lipase-dependent and independent effects, indicating that both this and other bacterial factors contribute to Corynebacterium-mediated protection in the airway. We also identified a previously uncharacterized bacterial lipase in C. amycolatum that is required for inhibition of S. pneumoniae growth in vitro. Together, these findings demonstrate the protective potential of airway Corynebacterium species and establish a new model for investigating the impact of commensal microbiota, such as Corynebacterium, on maintaining respiratory health.
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Affiliation(s)
- Kadi J. Horn
- Department of Otolaryngology Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO, United States
| | - Alexander C. Jaberi Vivar
- Department of Otolaryngology Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Developmental Biology, Washington University in St. Louis, St. Louis, MO, United States
| | - Vera Arenas
- Department of Otolaryngology Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Sameer Andani
- Department of Otolaryngology Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO, United States
| | - Edward N. Janoff
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, CO, United States
- Denver Veterans Affairs Medical Center, Aurora, CO, United States
| | - Sarah E. Clark
- Department of Otolaryngology Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO, United States
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