1
|
Argüeso P, Woodward AM, AbuSamra DB. The Epithelial Cell Glycocalyx in Ocular Surface Infection. Front Immunol 2021; 12:729260. [PMID: 34497615 PMCID: PMC8419333 DOI: 10.3389/fimmu.2021.729260] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/09/2021] [Indexed: 12/30/2022] Open
Abstract
The glycocalyx is the main component of the transcellular barrier located at the interface between the ocular surface epithelia and the external environment. This barrier extends up to 500 nm from the plasma membrane and projects into the tear fluid bathing the surface of the eye. Under homeostatic conditions, defense molecules in the glycocalyx, such as transmembrane mucins, resist infection. However, many pathogenic microorganisms have evolved to exploit components of the glycocalyx in order to gain access to epithelial cells and consequently exert deleterious effects. This manuscript reviews the implications of the ocular surface epithelial glycocalyx to bacterial, viral, fungal and parasitic infection. Moreover, it presents some ongoing controversies surrounding the functional relevance of the epithelial glycocalyx to ocular infectious disease.
Collapse
Affiliation(s)
- Pablo Argüeso
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Ashley M Woodward
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Dina B AbuSamra
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
2
|
Classification, structural biology, and applications of mucin domain-targeting proteases. Biochem J 2021; 478:1585-1603. [DOI: 10.1042/bcj20200607] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/14/2021] [Accepted: 03/17/2021] [Indexed: 12/11/2022]
Abstract
Epithelial surfaces throughout the body are coated by mucins, a class of proteins carrying domains characterized by a high density of O-glycosylated serine and threonine residues. The resulting mucosal layers form crucial host-microbe interfaces that prevent the translocation of microbes while also selecting for distinct bacteria via the presented glycan repertoire. The intricate interplay between mucus production and breakdown thus determines the composition of the microbiota maintained within these mucosal environments, which can have a large influence on the host during both homeostasis and disease. Most research to date on mucus breakdown has focused on glycosidases that trim glycan structures to release monosaccharides as a source of nutrients. More recent work has uncovered the existence of mucin-type O-glycosylation-dependent proteases that are secreted by pathogens, commensals, and mutualists to facilitate mucosal colonization and penetration. Additionally, immunoglobulin A (IgA) proteases promote bacterial colonization in the presence of neutralizing secretory IgA through selective cleavage of the heavily O-glycosylated hinge region. In this review, we summarize families of O-glycoproteases and IgA proteases, discuss known structural features, and review applications of these enzymes to glycobiology.
Collapse
|
3
|
Ung L, Bispo PJM, Bryan NC, Andre C, Chodosh J, Gilmore MS. The Best of All Worlds: Streptococcus pneumoniae Conjunctivitis through the Lens of Community Ecology and Microbial Biogeography. Microorganisms 2019; 8:microorganisms8010046. [PMID: 31881682 PMCID: PMC7022640 DOI: 10.3390/microorganisms8010046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/16/2019] [Accepted: 12/21/2019] [Indexed: 12/16/2022] Open
Abstract
The study of the forces which govern the geographical distributions of life is known as biogeography, a subject which has fascinated zoologists, botanists and ecologists for centuries. Advances in our understanding of community ecology and biogeography—supported by rapid improvements in next generation sequencing technology—have now made it possible to identify and explain where and why life exists as it does, including within the microbial world. In this review, we highlight how a unified model of microbial biogeography, one which incorporates the classic ecological principles of selection, diversification, dispersion and ecological drift, can be used to explain community dynamics in the settings of both health and disease. These concepts operate on a multiplicity of temporal and spatial scales, and together form a powerful lens through which to study microbial population structures even at the finest anatomical resolutions. When applied specifically to curious strains of conjunctivitis-causing, nonencapsulated Streptococcus pneumoniae, we show how this conceptual framework can be used to explain the possible evolutionary and disease-causing mechanisms which allowed these lineages to colonize and invade a separate biogeography. An intimate knowledge of this radical bifurcation in phylogeny, still the only known niche subspecialization for S. pneumoniae to date, is critical to understanding the pathogenesis of ocular surface infections, nature of host-pathogen interactions, and developing strategies to curb disease transmission.
Collapse
Affiliation(s)
- Lawson Ung
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Paulo J. M. Bispo
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Noelle C. Bryan
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
- Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences, Cambridge, MA 02139, USA
| | - Camille Andre
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - James Chodosh
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Michael S. Gilmore
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
- Correspondence: ; Tel.: +1-617-523-7900
| |
Collapse
|
4
|
Dumesnil A, Auger JP, Roy D, Vötsch D, Willenborg M, Valentin-Weigand P, Park PW, Grenier D, Fittipaldi N, Harel J, Gottschalk M. Characterization of the zinc metalloprotease of Streptococcus suis serotype 2. Vet Res 2018; 49:109. [PMID: 30373658 PMCID: PMC6206940 DOI: 10.1186/s13567-018-0606-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/16/2018] [Indexed: 11/22/2022] Open
Abstract
Streptococcus suis is a swine pathogen and zoonotic agent responsible for meningitis and septic shock. Although several putative virulence factors have been described, the initial steps of the S. suis pathogenesis remain poorly understood. While controversial results have been reported for a S. suis serotype 2 zinc metalloprotease (Zmp) regarding its IgA protease activity, recent phylogenetic analyses suggested that this protein is homologous to the ZmpC of Streptococcus pneumoniae, which is not an IgA protease. Based on the previously described functions of metalloproteases (including IgA protease and ZmpC), different experiments were carried out to study the activities of that of S. suis serotype 2. First, results showed that S. suis, as well as the recombinant Zmp, were unable to cleave human IgA1, confirming lack of IgA protease activity. Similarly, S. suis was unable to cleave P-selectin glycoprotein ligand-1 and to activate matrix metalloprotease 9, at least under the conditions tested. However, S. suis was able to partially cleave mucin 16 and syndecan-1 ectodomains. Experiments carried out with an isogenic Δzmp mutant showed that the Zmp protein was partially involved in such activities. The absence of a functional Zmp protein did not affect the ability of S. suis to adhere to porcine bronchial epithelial cells in vitro, or to colonize the upper respiratory tract of pigs in vivo. Taken together, our results show that S. suis serotype 2 Zmp is not a critical virulence factor and highlight the importance of independently confirming results on S. suis virulence by different teams.
Collapse
Affiliation(s)
- Audrey Dumesnil
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - Jean-Philippe Auger
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - David Roy
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - Désirée Vötsch
- Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Maren Willenborg
- Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Peter Valentin-Weigand
- Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Pyong Woo Park
- Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniel Grenier
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Oral Ecology Research Group, Faculty of Dentistry, Laval University, Quebec City, QC, Canada
| | - Nahuel Fittipaldi
- Public Health Ontario Laboratory Toronto, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Josée Harel
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada. .,Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.
| |
Collapse
|
5
|
Surface proteins involved in the adhesion of Streptococcus salivarius to human intestinal epithelial cells. Appl Microbiol Biotechnol 2018; 102:2851-2865. [PMID: 29442170 PMCID: PMC5847202 DOI: 10.1007/s00253-018-8794-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 01/10/2018] [Accepted: 01/14/2018] [Indexed: 01/08/2023]
Abstract
The adhesion properties of 14 Streptococcus salivarius strains to mucus (HT29-MTX) and non-mucus secreting (Caco-2/TC7) human intestinal epithelial cells were investigated. Ability to adhere to these two eukaryotic cell lines greatly differs between strains. The presence of mucus played a major factor in adhesion, likely due to high adhesiveness to mucins present in the native human mucus layer covering the whole cell surface. Only one S. salivarius strain (F6-1), isolated from the feces of a healthy baby, was found to strongly adhere to HT-29 MTX cells at a level comparable to that of Lactobacillus rhamnosus GG, a probiotic strain considered to be highly adherent. By sequencing the genome of F6-1, we were able to identify 36 genes encoding putative surface proteins. Deletion mutants were constructed for six of them and their adhesion abilities on HT-29 MTX cells were checked. Our study confirmed that four of these genes encode adhesins involved in the adhesion of S. salivarius to host cells. Such adhesins were also identified in other S. salivarius strains.
Collapse
|
6
|
Gipson IK, Mandel U, Menon B, Michaud S, Tisdale A, Campos D, Clausen H. Generation and characterization of a monoclonal antibody to the cytoplasmic tail of MUC16. Glycobiology 2017; 27:920-926. [PMID: 28673046 PMCID: PMC6283312 DOI: 10.1093/glycob/cwx054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/23/2017] [Accepted: 06/05/2017] [Indexed: 12/28/2022] Open
Abstract
MUC16 is a large transmembrane mucin expressed on the apical surfaces of the epithelium covering the ocular surface, respiratory system and female reproductive tract. The transmembrane mucin is overexpressed by ovarian carcinomas, it is one of the most frequently used diagnostic markers for the disease and it is considered a promising target for immunotherapeutic intervention. Immunodetection of the mucin has to date been through antibodies that recognize its exceptionally large ectodomain. Similar to other membrane anchored mucins, MUC16 has a short cytoplasmic tail (CT), but studies of the biological relevance of the C-terminal domain of MUC16 has been limited by lack of availability of monoclonal antibodies that recognize the native CT. Here, we report the development of a novel monoclonal antibody to the CT region of the molecule that recognizes native MUC16 and its enzymatically released CT region. The antibody is useful for immunoprecipitation of the released CT domain as demonstrated with the OVCAR3 ovarian cancer cell line and can be used for detailed cytolocalization in cells as well as in frozen sections of ocular surface and uterine epithelium.
Collapse
Affiliation(s)
- Ilene K Gipson
- Department of Ophthalmology Harvard Medical School, Schepens Eye Research Institute/MEEI, Boston, MA 02114, USA
| | - Ulla Mandel
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Balaraj Menon
- Department of Ophthalmology Harvard Medical School, Schepens Eye Research Institute/MEEI, Boston, MA 02114, USA
| | - Sandra Michaud
- Department of Ophthalmology Harvard Medical School, Schepens Eye Research Institute/MEEI, Boston, MA 02114, USA
| | - Ann Tisdale
- Department of Ophthalmology Harvard Medical School, Schepens Eye Research Institute/MEEI, Boston, MA 02114, USA
| | - Diana Campos
- Instituto de Investigação e Inovação e Saúde, Universidade do Porto, Rua Júlio Amaral de Carvalho 45, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Rua Júlio Amaral de Carvalho 45, Porto, Portugal
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| |
Collapse
|
7
|
Barenkamp SJ, Chonmaitree T, Hakansson AP, Heikkinen T, King S, Nokso-Koivisto J, Novotny LA, Patel JA, Pettigrew M, Swords WE. Panel 4: Report of the Microbiology Panel. Otolaryngol Head Neck Surg 2017; 156:S51-S62. [PMID: 28372529 PMCID: PMC5490388 DOI: 10.1177/0194599816639028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 02/24/2016] [Indexed: 12/12/2022]
Abstract
Objective To perform a comprehensive review of the literature from July 2011 until June 2015 on the virology and bacteriology of otitis media in children. Data Sources PubMed database of the National Library of Medicine. Review Methods Two subpanels comprising experts in the virology and bacteriology of otitis media were created. Each panel reviewed the relevant literature in the fields of virology and bacteriology and generated draft reviews. These initial reviews were distributed to all panel members prior to meeting together at the Post-symposium Research Conference of the 18th International Symposium on Recent Advances in Otitis Media, National Harbor, Maryland, in June 2015. A final draft was created, circulated, and approved by all panel members. Conclusions Excellent progress has been made in the past 4 years in advancing our understanding of the microbiology of otitis media. Numerous advances were made in basic laboratory studies, in animal models of otitis media, in better understanding the epidemiology of disease, and in clinical practice. Implications for Practice (1) Many viruses cause acute otitis media without bacterial coinfection, and such cases do not require antibiotic treatment. (2) When respiratory syncytial virus, metapneumovirus, and influenza virus peak in the community, practitioners can expect to see an increase in clinical otitis media cases. (3) Biomarkers that predict which children with upper respiratory tract infections will develop otitis media may be available in the future. (4) Compounds that target newly identified bacterial virulence determinants may be available as future treatment options for children with otitis media.
Collapse
Affiliation(s)
- Stephen J. Barenkamp
- Department of Pediatrics, St Louis University School of Medicine, St Louis, Missouri, USA
| | - Tasnee Chonmaitree
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | | | - Terho Heikkinen
- Department of Pediatrics, University of Turku and Turku University Hospital, Turku, Finland
| | - Samantha King
- The Research Institute at Nationwide Children’s Hospital and Ohio State University, Columbus, Ohio, USA
| | - Johanna Nokso-Koivisto
- Department of Otorhinolaryngology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Laura A. Novotny
- The Research Institute at Nationwide Children’s Hospital and Ohio State University, Columbus, Ohio, USA
| | - Janak A. Patel
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | - Melinda Pettigrew
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - W. Edward Swords
- Department of Microbiology and Immunology, Wake Forest University, Winston-Salem, North Carolina, USA
| |
Collapse
|
8
|
Gómez LA, Alvarez FI, Fernández PA, Flores MR, Molina RE, Coloma RF, Oñate AA. Immunogenicity and Protective Response Induced by Recombinant Plasmids Based on the BAB1_0267 and BAB1_0270 Open Reading Frames of Brucella abortus 2308 in BALB/c Mice. Front Cell Infect Microbiol 2016; 6:117. [PMID: 27747197 PMCID: PMC5041321 DOI: 10.3389/fcimb.2016.00117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/16/2016] [Indexed: 01/05/2023] Open
Abstract
Immunogenicity induced by recombinant plasmids based on the BAB1_0267 and BAB1_0270 open reading frames (ORFs) of Brucella abortus 2308 was evaluated. Bioinformatics analyses indicate that the BAB1_0267 and BAB1_0270 ORFs encode a protein with a SH3 domain and a Zn-dependent metalloproteinase, respectively. Both ORFs have important effects on intracellular survival and replication of B. abortus 2308, mediated via professional and non-professional phagocytic cells. Our results show that immunization with the recombinant plasmid based on the BAB1_0267 ORF significantly increases the production of IgG1, levels of IFN-γ and the lymphoproliferative response of splenocytes. However, BAB1_0267 did not provide significant levels of protection. The plasmid based on the BAB1_0270 significantly increased IgG2a production, levels of IFN-γ and TNF-α, and the lymphoproliferative response of splenocytes. These results demonstrate that immunization with the BAB1_0270 derived recombinant plasmid induce a Th1-type immune response, correlated with a heightened resistance to B. abortus 2308 infection in mice. It is concluded that the Th1-type immune response against bacterial Zn-dependent metalloproteinase induces a protective response in mice, and that pV270 recombinant plasmid is an effective candidate microbicide against brucellosis.
Collapse
Affiliation(s)
- Leonardo A Gómez
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Francisco I Alvarez
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Pablo A Fernández
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Manuel R Flores
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Raúl E Molina
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Roberto F Coloma
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Angel A Oñate
- Laboratory of Molecular Immunology, Department of Immunology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| |
Collapse
|
9
|
Epidemic Keratoconjunctivitis-Causing Adenoviruses Induce MUC16 Ectodomain Release To Infect Ocular Surface Epithelial Cells. mSphere 2016; 1:mSphere00112-15. [PMID: 27303700 PMCID: PMC4863608 DOI: 10.1128/msphere.00112-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 01/13/2016] [Indexed: 01/26/2023] Open
Abstract
Human adenoviruses (HAdVs) are double-stranded DNA viruses that cause infections across all mucosal tissues in the body. At the ocular surface, HAdVs cause keratoconjunctivitis (E. Ford, K. E. Nelson, and D. Warren, Epidemiol Rev 9:244–261, 1987, and C. M. Robinson, D. Seto, M. S. Jones, D. W. Dyer, and J. Chodosh, Infect Genet Evol 11:1208–1217, 2011, doi:10.1016/j.meegid.2011.04.031)—a highly contagious infection that accounts for nearly 60% of conjunctivitis cases in the United States (R. P. Sambursky, N. Fram, and E. J. Cohen, Optometry 78:236–239, 2007, doi:10.1016/j.optm.2006.11.012, and A. M. Pihos, J Optom 6:69–74, 2013, doi:10.1016/j.optom.2012.08.003). The infection begins with HAdV entry within ocular surface epithelial cells; however, the mechanisms used by HAdVs to transit the otherwise protective mucosal barrier of ocular surface epithelial cells prior to entry remain unknown. Here, we report that the highly virulent keratoconjunctivitis-causing HAdV-D37 induces release of the extracellular domain (ectodomain) of MUC16, a major component of the mucosal barrier of ocular surface epithelial cells, prior to infecting underlying cells. Currently, there is no specific treatment for controlling this infection. Understanding the early steps involved in the pathogenesis of keratoconjunctivitis and using this information to intercept adenoviral entry within cells may guide the development of novel strategies for controlling the infection. Human adenoviruses (HAdV), species D in particular (HAdV-D), are frequently associated with epidemic keratoconjunctivitis (EKC). Although the infection originates at the ocular surface epithelium, the mechanisms by which HAdV-Ds bypass the membrane-associated mucin (MAM)-rich glycocalyx of the ocular surface epithelium to trigger infection and inflammation remain unknown. Here, we report that an EKC-causing adenovirus (HAdV-D37), but not a non-EKC-causing one (HAdV-D19p), induces ectodomain release of MUC16—a MAM with barrier functions at the ocular surface—from cultured human corneal and conjunctival epithelial cells. HAdV-D37, but not HAdV-D19p, is also found to decrease the glycocalyx barrier function of corneal epithelial cells, as determined by rose bengal dye penetrance assays. Furthermore, results from quantitative PCR (qPCR) amplification of viral genomic DNA using primers specific to a conserved region of the E1B gene show that, in comparison to infection by HAdV-D19p, infection by HAdV-D37 is significantly increased in corneal epithelial cells. Collectively, these results point to a MUC16 ectodomain release-dependent mechanism utilized by the EKC-causing HAdV-D37 to initiate infection at the ocular surface. These findings are important in terms of understanding the pathogenesis of adenoviral keratoconjunctivitis. Similar MAM ectodomain release mechanisms may be prevalent across other mucosal epithelia in the body (e.g., the airway epithelium) that are prone to adenoviral infection. IMPORTANCE Human adenoviruses (HAdVs) are double-stranded DNA viruses that cause infections across all mucosal tissues in the body. At the ocular surface, HAdVs cause keratoconjunctivitis (E. Ford, K. E. Nelson, and D. Warren, Epidemiol Rev 9:244–261, 1987, and C. M. Robinson, D. Seto, M. S. Jones, D. W. Dyer, and J. Chodosh, Infect Genet Evol 11:1208–1217, 2011, doi:10.1016/j.meegid.2011.04.031)—a highly contagious infection that accounts for nearly 60% of conjunctivitis cases in the United States (R. P. Sambursky, N. Fram, and E. J. Cohen, Optometry 78:236–239, 2007, doi:10.1016/j.optm.2006.11.012, and A. M. Pihos, J Optom 6:69–74, 2013, doi:10.1016/j.optom.2012.08.003). The infection begins with HAdV entry within ocular surface epithelial cells; however, the mechanisms used by HAdVs to transit the otherwise protective mucosal barrier of ocular surface epithelial cells prior to entry remain unknown. Here, we report that the highly virulent keratoconjunctivitis-causing HAdV-D37 induces release of the extracellular domain (ectodomain) of MUC16, a major component of the mucosal barrier of ocular surface epithelial cells, prior to infecting underlying cells. Currently, there is no specific treatment for controlling this infection. Understanding the early steps involved in the pathogenesis of keratoconjunctivitis and using this information to intercept adenoviral entry within cells may guide the development of novel strategies for controlling the infection.
Collapse
|
10
|
Barnett TC, Cole JN, Rivera-Hernandez T, Henningham A, Paton JC, Nizet V, Walker MJ. Streptococcal toxins: role in pathogenesis and disease. Cell Microbiol 2015; 17:1721-41. [PMID: 26433203 DOI: 10.1111/cmi.12531] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/13/2015] [Accepted: 09/02/2015] [Indexed: 12/15/2022]
Abstract
Group A Streptococcus (Streptococcus pyogenes), group B Streptococcus (Streptococcus agalactiae) and Streptococcus pneumoniae (pneumococcus) are host-adapted bacterial pathogens among the leading infectious causes of human morbidity and mortality. These microbes and related members of the genus Streptococcus produce an array of toxins that act against human cells or tissues, resulting in impaired immune responses and subversion of host physiological processes to benefit the invading microorganism. This toxin repertoire includes haemolysins, proteases, superantigens and other agents that ultimately enhance colonization and survival within the host and promote dissemination of the pathogen.
Collapse
Affiliation(s)
- Timothy C Barnett
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Jason N Cole
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia.,Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Tania Rivera-Hernandez
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Anna Henningham
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia.,Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Victor Nizet
- Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Mark J Walker
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| |
Collapse
|
11
|
Menon BB, Kaiser-Marko C, Spurr-Michaud S, Tisdale AS, Gipson IK. Suppression of Toll-like receptor-mediated innate immune responses at the ocular surface by the membrane-associated mucins MUC1 and MUC16. Mucosal Immunol 2015; 8:1000-8. [PMID: 25563498 PMCID: PMC4495011 DOI: 10.1038/mi.2014.127] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 12/01/2014] [Indexed: 02/04/2023]
Abstract
Membrane-associated mucins (MAMs) expressed on the ocular surface epithelium form a dense glycocalyx that is hypothesized to protect the cornea and conjunctiva from external insult. In this study, the hypothesis that the MAMs MUC1 and MUC16, expressed on the apical surface of the corneal epithelium, suppress Toll-like receptor (TLR)-mediated innate immune responses was tested. Using an in vitro model of corneal epithelial cells that are cultured to express MAMs, we show that reduced expression of either MUC1 or MUC16 correlates with increased message and secreted protein levels of the proinflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor-α (TNF-α) following exposure of cells to the TLR2 and TLR5 agonists, heat-killed Listeria monocytogenes and flagellin, respectively. As mice express Muc1 (but not Muc16) in the corneal epithelium, a Muc1(-/-) mouse model was used to extend in vitro findings. Indeed, IL-6 and TNF-α message levels were increased in the corneal epithelium of Muc1(-/-) mice, in comparison with wild-type mice, following exposure of enucleated eyes to the TLR2 and TLR5 agonists. Our results suggest that the MAMs MUC1 and MUC16 contribute to the maintenance of immune homeostasis at the ocular surface by limiting TLR-mediated innate immune responses.
Collapse
Affiliation(s)
- Balaraj B. Menon
- Address correspondence to: Balaraj B. Menon, Ph.D., Schepens Eye Research Institute, Massachusetts Eye and Ear, 20 Staniford St., Boston, MA 02114, Tel: 617-912-0217,
| | | | | | | | | |
Collapse
|
12
|
Valentino MD, McGuire AM, Rosch JW, Bispo PJM, Burnham C, Sanfilippo CM, Carter RA, Zegans ME, Beall B, Earl AM, Tuomanen EI, Morris TW, Haas W, Gilmore MS. Unencapsulated Streptococcus pneumoniae from conjunctivitis encode variant traits and belong to a distinct phylogenetic cluster. Nat Commun 2014; 5:5411. [PMID: 25388376 PMCID: PMC4231546 DOI: 10.1038/ncomms6411] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 09/29/2014] [Indexed: 11/13/2022] Open
Abstract
Streptococcus pneumoniae, an inhabitant of the upper respiratory mucosa, causes respiratory and invasive infections as well as conjunctivitis. Strains that lack the capsule, a main virulence factor and the target of current vaccines, are often isolated from conjunctivitis cases. Here we perform a comparative genomic analysis of 271 strains of conjunctivitis-causing S. pneumoniae from 72 postal codes in the United States. We find that the vast majority of conjunctivitis strains are members of a distinct cluster of closely related unencapsulated strains. These strains possess divergent forms of pneumococcal virulence factors (such as CbpA and neuraminidases) that are not shared with other unencapsulated nasopharyngeal S. pneumoniae. They also possess putative adhesins that have not been described in encapsulated pneumococci. These findings suggest that the unencapsulated strains capable of causing conjunctivitis utilize a pathogenesis strategy substantially different from that described for S. pneumoniae at other infection sites.
Collapse
Affiliation(s)
- Michael D. Valentino
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles St. C703, Boston, MA 02114, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, 77 Ave Louis Pasteur, Boston, MA 02115, USA
- The Broad Institute of MIT and Harvard, 320 Charles St. Cambridge, MA 02141, USA
| | | | - Jason W. Rosch
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, 262 Danny Thomas Pl., Memphis, TN 38105, USA
| | - Paulo J. M. Bispo
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles St. C703, Boston, MA 02114, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, 77 Ave Louis Pasteur, Boston, MA 02115, USA
| | - Corinna Burnham
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, 262 Danny Thomas Pl., Memphis, TN 38105, USA
| | | | - Robert A. Carter
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, 262 Danny Thomas Pl., Memphis, TN 38105, USA
| | - Michael E. Zegans
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, 1 Rope Ferry Rd., Hanover, NH 03755, USA
| | - Bernard Beall
- Streptococcus Laboratory, Centers for Disease Control and Prevention, 1600 Clifton Rd., Atlanta, GA 30333, USA
| | - Ashlee M. Earl
- The Broad Institute of MIT and Harvard, 320 Charles St. Cambridge, MA 02141, USA
| | - Elaine I. Tuomanen
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, 262 Danny Thomas Pl., Memphis, TN 38105, USA
| | - Timothy W. Morris
- Bausch and Lomb, Inc., 1400 Goodman St. N., Rochester, NY 14609, USA
| | - Wolfgang Haas
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles St. C703, Boston, MA 02114, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, 77 Ave Louis Pasteur, Boston, MA 02115, USA
| | - Michael S. Gilmore
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles St. C703, Boston, MA 02114, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, 77 Ave Louis Pasteur, Boston, MA 02115, USA
- The Broad Institute of MIT and Harvard, 320 Charles St. Cambridge, MA 02141, USA
| |
Collapse
|
13
|
Honsa ES, Johnson MDL, Rosch JW. The roles of transition metals in the physiology and pathogenesis of Streptococcus pneumoniae. Front Cell Infect Microbiol 2013; 3:92. [PMID: 24364001 PMCID: PMC3849628 DOI: 10.3389/fcimb.2013.00092] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 11/19/2013] [Indexed: 01/01/2023] Open
Abstract
For bacterial pathogens whose sole environmental reservoir is the human host, the acquisition of essential nutrients, particularly transition metals, is a critical aspect of survival due to tight sequestration and limitation strategies deployed to curtail pathogen outgrowth. As such, these bacteria have developed diverse, specialized acquisition mechanisms to obtain these metals from the niches of the body in which they reside. To oppose the spread of infection, the human host has evolved multiple mechanisms to counter bacterial invasion, including sequestering essential metals away from bacteria and exposing bacteria to lethal concentrations of metals. Hence, to maintain homeostasis within the host, pathogens must be able to acquire necessary metals from host proteins and to export such metals when concentrations become detrimental. Furthermore, this acquisition and efflux equilibrium must occur in a tissue-specific manner because the concentration of metals varies greatly within the various microenvironments of the human body. In this review, we examine the functional roles of the metal import and export systems of the Gram-positive pathogen Streptococcus pneumoniae in both signaling and pathogenesis.
Collapse
Affiliation(s)
- Erin S Honsa
- Department of Infectious Diseases, St. Jude Children's Research Hospital Memphis, TN, USA
| | - Michael D L Johnson
- Department of Infectious Diseases, St. Jude Children's Research Hospital Memphis, TN, USA
| | - Jason W Rosch
- Department of Infectious Diseases, St. Jude Children's Research Hospital Memphis, TN, USA
| |
Collapse
|