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Park SS, Gonzalez-Juarbe N, Martínez E, Hale JY, Lin YH, Huffines JT, Kruckow KL, Briles DE, Orihuela CJ. Streptococcus pneumoniae Binds to Host Lactate Dehydrogenase via PspA and PspC To Enhance Virulence. mBio 2021; 12:e00673-21. [PMID: 33947761 PMCID: PMC8437407 DOI: 10.1128/mbio.00673-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 02/06/2023] Open
Abstract
Pneumococcal surface protein A (PspA) and pneumococcal surface protein C (PspC, also called CbpA) are major virulence factors of Streptococcus pneumoniae (Spn). These surface-exposed choline-binding proteins (CBPs) function independently to inhibit opsonization, neutralize antimicrobial factors, or serve as adhesins. PspA and PspC both carry a proline-rich domain (PRD) whose role, other than serving as a flexible connector between the N-terminal and C-terminal domains, was up to this point unknown. Herein, we demonstrate that PspA binds to lactate dehydrogenase (LDH) released from dying host cells during infection. Using recombinant versions of PspA and isogenic mutants lacking PspA or specific domains of PspA, this property was mapped to a conserved 22-amino-acid nonproline block (NPB) found within the PRD of most PspAs and PspCs. The NPB of PspA had specific affinity for LDH-A, which converts pyruvate to lactate. In a mouse model of pneumonia, preincubation of Spn carrying NPB-bearing PspA with LDH-A resulted in increased bacterial titers in the lungs. In contrast, incubation of Spn carrying a version of PspA lacking the NPB with LDH-A or incubation of wild-type Spn with enzymatically inactive LDH-A did not enhance virulence. Preincubation of NPB-bearing Spn with lactate alone enhanced virulence in a pneumonia model, indicating exogenous lactate production by Spn-bound LDH-A had an important role in pneumococcal pathogenesis. Our observations show that lung LDH, released during the infection, is an important binding target for Spn via PspA/PspC and that pneumococci utilize LDH-A derived lactate for their benefit in vivoIMPORTANCEStreptococcus pneumoniae (Spn) is the leading cause of community-acquired pneumonia. PspA and PspC are among its most important virulence factors, and these surface proteins carry the proline-rich domain (PRD), whose role was unknown until now. Herein, we show that a conserved 22-amino-acid nonproline block (NPB) found within most versions of the PRD binds to host-derived lactate dehydrogenase A (LDH-A), a metabolic enzyme which converts pyruvate to lactate. PspA-mediated binding of LDH-A increased Spn titers in the lungs and this required LDH-A enzymatic activity. Enhanced virulence was also observed when Spn was preincubated with lactate, suggesting LDH-A-derived lactate is a vital food source. Our findings define a role for the NPB of the PRD and show that Spn co-opts host enzymes for its benefit. They advance our understanding of pneumococcal pathogenesis and have key implications on the susceptibility of individuals with preexisting airway damage that results in LDH-A release.
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Affiliation(s)
- Sang-Sang Park
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Norberto Gonzalez-Juarbe
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, USA
| | - Eriel Martínez
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Joanetha Yvette Hale
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yi-Han Lin
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, USA
| | - Joshua T Huffines
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Katherine L Kruckow
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - David E Briles
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Carlos J Orihuela
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
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Fuji N, Pichichero ME, Kaur R. Comparison of specific in-vitro virulence gene expression and innate host response in locally invasive vs colonizer strains of Streptococcus pneumoniae. Med Microbiol Immunol 2021; 210:111-120. [PMID: 33751214 DOI: 10.1007/s00430-021-00701-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 02/27/2021] [Indexed: 10/21/2022]
Abstract
Among Rochester NY children, a dramatic increase in nasopharyngeal (NP) colonization by non-vaccine pneumococcal serotypes 35B and 15A occurred during years 2010-2015, after introduction of 13-valent pneumococcal conjugate vaccine (PCV13). In our population, serotype 35B strains colonized in the nasopharynx (NP) but infrequently caused acute otitis media (AOM) whereas serotype 15A strains displayed virulence, evidenced by causing AOM. To explain the virulence difference, virulence genes expression between 35B and 15A, as well as the host's immune response during asymptomatic colonization were analyzed. We investigated differences in regulation of 19 virulence genes for differences in virulence using RT-PCR in 20 35B and 14 15A strains and measured gene expression of 9 host innate cytokines in the NP to assess the mucosal inflammatory response during asymptomatic colonization. Comparing 35B versus 15A strains, genes for competence ComA and RrgC were upregulated; capsular (Cps2D) and virulence genes (PfbA, PcpA and PhtE) were downregulated among 35B strains. PavB, LytA, LytB, NanA, CiaR, PhtD, LuxS, PspA and pneumolysin (Ply) showed no difference. IL17 and IL23 gene expression were > tenfold higher during 35B compared to 15A strain asymptomatic colonization. Only IL23 showed significant difference. In the first 5 years after introduction of PCV13, serotype 35B strains emerged as asymptomatic colonizers and 15A strains emerged to cause AOM in young children. Various genes (PfbA, PcpA, Cps2D and PhtE) among tested in this analysis were downregulated in 35B whereas ComA and RrgC were significantly upregulated. For the host's cytokine response, IL23 proinflammatory response which is essential for the differentiation of Th17 lymphocytes in the NP of children with 35B strains was significantly higher than the response to 15A during asymptomatic colonization.
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Affiliation(s)
- Naoko Fuji
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY, 14621, USA
| | - Michael E Pichichero
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY, 14621, USA
| | - Ravinder Kaur
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY, 14621, USA.
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Root-Bernstein R. Possible Cross-Reactivity between SARS-CoV-2 Proteins, CRM197 and Proteins in Pneumococcal Vaccines May Protect Against Symptomatic SARS-CoV-2 Disease and Death. Vaccines (Basel) 2020; 8:E559. [PMID: 32987794 PMCID: PMC7712751 DOI: 10.3390/vaccines8040559] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/15/2020] [Accepted: 09/16/2020] [Indexed: 01/08/2023] Open
Abstract
Various studies indicate that vaccination, especially with pneumococcal vaccines, protects against symptomatic cases of SARS-CoV-2 infection and death. This paper explores the possibility that pneumococcal vaccines in particular, but perhaps other vaccines as well, contain antigens that might be cross-reactive with SARS-CoV-2 antigens. Comparison of the glycosylation structures of SARS-CoV-2 with the polysaccharide structures of pneumococcal vaccines yielded no obvious similarities. However, while pneumococcal vaccines are primarily composed of capsular polysaccharides, some are conjugated to cross-reacting material CRM197, a modified diphtheria toxin, and all contain about three percent protein contaminants, including the pneumococcal surface proteins PsaA, PspA and probably PspC. All of these proteins have very high degrees of similarity, using very stringent criteria, with several SARS-CoV-2 proteins including the spike protein, membrane protein and replicase 1a. CRM197 is also present in Haemophilus influenzae type b (Hib) and meningitis vaccines. Equivalent similarities were found at lower rates, or were completely absent, among the proteins in diphtheria, tetanus, pertussis, measles, mumps, rubella, and poliovirus vaccines. Notably, PspA and PspC are highly antigenic and new pneumococcal vaccines based on them are currently in human clinical trials so that their effectiveness against SARS-CoV-2 disease is easily testable.
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The Modified Surface Killing Assay Distinguishes between Protective and Nonprotective Antibodies to PspA. mSphere 2019; 4:4/6/e00589-19. [PMID: 31826968 PMCID: PMC6908419 DOI: 10.1128/msphere.00589-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The most important finding of this study is that the MSKA can be used as an in vitro functional assay. Such an assay will be critical for the development of PspA-containing vaccines. The other important findings relate to the locations and nature of the protection-eliciting epitopes of PspA. There are limited prior data on the locations of protection-eliciting PspA epitopes, but those data along with the data presented here make it clear that there is not a single epitope or domain of PspA that can elicit protective antibody and there exists at least one region of the αHD which seldom elicits protective antibody. Moreover, these data, in concert with prior data, strongly make the case that protective epitopes in the αHD are highly conformational (≥100-amino-acid fragments of the αHD are required), whereas at least some protection-eliciting epitopes in the proline-rich domain are encoded by ≤15-amino-acid sequences. Pneumococcal surface protein A (PspA) elicits antibody protective against lethal challenge by Streptococcus pneumoniae and is a candidate noncapsular antigen for inclusion in vaccines. Evaluation of immunity to PspA in human trials would be greatly facilitated by an in vitro functional assay able to distinguish protective from nonprotective antibodies to PspA. Mouse monoclonal antibodies (MAbs) to PspA can mediate killing by human granulocytes in the modified surface killing assay (MSKA). To determine if the MSKA can distinguish between protective and nonprotective MAbs, we examined seven MAbs to PspA. All bound recombinant PspA, as detected by enzyme-linked immunosorbent assay and Western blotting; four gave strong passive protection against fatal challenge, two were nonprotective, and the seventh one only delayed death. The four that were able to provide strong passive protection were also most able to enhance killing in the MSKA, the two that were not protective in mice were not effective in the MSKA, and the MAb that was only weakly protective in mice was weakly effective in the MSKA (P < 0.001). One of the four most protective MAbs tested reacted to the proline-rich domain of PspA. Two of the other most protective MAbs and the weakly protective MAb reacted with a fragment from PspA’s α-helical domain (αHD), containing amino acids (aa) 148 to 247 from the N terminus of PspA. The fourth highly protective MAb recognized none of the overlapping 81- or 100-aa fragments of PspA. The two nonprotective MAbs recognized a more N-terminal αHD fragment (aa 48 to 147). IMPORTANCE The most important finding of this study is that the MSKA can be used as an in vitro functional assay. Such an assay will be critical for the development of PspA-containing vaccines. The other important findings relate to the locations and nature of the protection-eliciting epitopes of PspA. There are limited prior data on the locations of protection-eliciting PspA epitopes, but those data along with the data presented here make it clear that there is not a single epitope or domain of PspA that can elicit protective antibody and there exists at least one region of the αHD which seldom elicits protective antibody. Moreover, these data, in concert with prior data, strongly make the case that protective epitopes in the αHD are highly conformational (≥100-amino-acid fragments of the αHD are required), whereas at least some protection-eliciting epitopes in the proline-rich domain are encoded by ≤15-amino-acid sequences.
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Animal models of acute otitis media - A review with practical implications for laboratory research. Eur Ann Otorhinolaryngol Head Neck Dis 2018; 135:183-190. [PMID: 29656888 DOI: 10.1016/j.anorl.2017.06.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Revised: 06/08/2017] [Accepted: 06/12/2017] [Indexed: 11/23/2022]
Abstract
Considerable animal research has focused on developing new strategies for the prevention and treatment of acute otitis media (AOM). Several experimental models of AOM have thus been developed. A PubMed search of the English literature was conducted from 1975 to July 2016 using the search terms "animal model" and "otitis media" from which 91 published studies were included for analysis, yielding 123 animal models. The rat, mouse and chinchilla are the preferred animals for experimental AOM models with their individual advantages and disadvantages. The most common pathogens used to create AOM are Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. Streptococcus pneumoniae (types 3, 23 and 6A) and non-typeable Haemophilus influenzae (NTHi) are best options for inoculation into rat and mouse models. Adding viral pathogens such as RSV and Influenza A virus, along with creating ET dysfunction, are useful adjuncts in animal models of AOM. Antibiotic prophylaxis may interfere with the inflammatory response without a significant reduction in animal mortality.
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Fernández FJ, Gómez S, Vega MC. Pathogens' toolbox to manipulate human complement. Semin Cell Dev Biol 2017; 85:98-109. [PMID: 29221973 DOI: 10.1016/j.semcdb.2017.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/30/2017] [Accepted: 12/03/2017] [Indexed: 12/15/2022]
Abstract
The surveillance and pathogen fighting functions of the complement system have evolved to protect mammals from life-threatening infections. In turn, pathogens have developed complex molecular mechanisms to subvert, divert and evade the effector functions of the complement. The study of complement immunoevasion by pathogens sheds light on their infection drivers, knowledge that is essential to implement therapies. At the same time, complement evasion also acts as a discovery ground that reveals important aspects of how complement works under physiological conditions. In recent years, complex interrelationships between infection insults and the onset of autoimmune and complement dysregulation diseases have led to propose that encounters with pathogens can act as triggering factors for disease. The correct management of these diseases involves the recognition of their triggering factors and the development and administration of complement-associated molecular therapies. Even more recently, unsuspected proteins from pathogens have been shown to possess moonlighting functions as virulence factors, raising the possibility that behind the first line of virulence factors there be many more pathogen proteins playing secondary, helping and supporting roles for the pathogen to successfully establish infections. In an era where antibiotics have a progressively reduced effect on the management and control of infectious diseases worldwide, knowledge on the mechanisms of pathogenic invasion and evasion look more necessary and pressing than ever.
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Affiliation(s)
| | - Sara Gómez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| | - M Cristina Vega
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
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Schachern PA, Kwon G, Briles DE, Ferrieri P, Juhn S, Cureoglu S, Paparella MM, Tsuprun V. Neutrophil Extracellular Traps and Fibrin in Otitis Media: Analysis of Human and Chinchilla Temporal Bones. JAMA Otolaryngol Head Neck Surg 2017; 143:990-995. [PMID: 28796849 DOI: 10.1001/jamaoto.2017.1320] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Bacterial resistance in acute otitis can result in bacterial persistence and biofilm formation, triggering chronic and recurrent infections. Objective To investigate the middle ear inflammatory response to bacterial infection in human and chinchilla temporal bones. Design, Setting, and Participants Six chinchillas underwent intrabullar inoculations with 0.5 mL of 106 colony-forming units (CFUs) of Streptococcus pneumoniae, serotype 2. Two days later, we counted bacteria in middle ear effusions postmortem. One ear from each chinchilla was processed in paraffin and sectioned at 5 µm. The opposite ear was embedded in epoxy resin, sectioned at a thickness of 1 µm, and stained with toluidine blue. In addition, we examined human temporal bones from 2 deceased donors with clinical histories of otitis media (1 with acute onset otitis media, 1 with recurrent infection). Temporal bones had been previously removed at autopsy, processed, embedded in celloidin, and cut at a thickness of 20 µm. Sections of temporal bones from both chinchillas and humans were stained with hematoxylin-eosin and immunolabeled with antifibrin and antihistone H4 antibodies. Main Outcome Measures Histopatological and imminohistochemical changes owing to otitis media. Results Bacterial counts in chinchilla middle ear effusions 2 days after inoculation were approximately 2 logs above initial inoculum counts. Both human and chinchilla middle ear effusions contained bacteria embedded in a fibrous matrix. Some fibers in the matrix showed positive staining with antifibrin antibody, others with antihistone H4 antibody. Conclusions and Relevance In acute and recurrent otitis media, fibrin and neutrophil extracellular traps (NETs) are part of the host inflammatory response to bacterial infection. In the early stages of otitis media the host defense system uses fibrin to entrap bacteria, and NETs function to eliminate bacteria. In chronic otitis media, fibrin and NETs appear to persist.
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Affiliation(s)
| | - Geeyoun Kwon
- Department of Otolaryngology University of Minnesota, Minneapolis
| | - David E Briles
- Department of Microbiology, University of Alabama at Birmingham, Birmingham
| | - Patricia Ferrieri
- Departments of Pediatrics, University of Minnesota, Minneapolis.,Laboratory Medicine and Pathology, University of Minnesota, Minneapolis
| | - Steven Juhn
- Department of Otolaryngology University of Minnesota, Minneapolis
| | | | | | - Vladimir Tsuprun
- Department of Otolaryngology University of Minnesota, Minneapolis
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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: 4] [Impact Index Per Article: 0.6] [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.
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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
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Keller LE, Bradshaw JL, Pipkins H, McDaniel LS. Surface Proteins and Pneumolysin of Encapsulated and Nonencapsulated Streptococcus pneumoniae Mediate Virulence in a Chinchilla Model of Otitis Media. Front Cell Infect Microbiol 2016; 6:55. [PMID: 27242973 PMCID: PMC4870244 DOI: 10.3389/fcimb.2016.00055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/02/2016] [Indexed: 11/13/2022] Open
Abstract
Streptococcus pneumoniae infections result in a range of human diseases and are responsible for almost one million deaths annually. Pneumococcal disease is mediated in part through surface structures and an anti-phagocytic capsule. Recent studies have shown that nonencapsulated S. pneumoniae (NESp) make up a significant portion of the pneumococcal population and are able to cause disease. NESp lack some common surface proteins expressed by encapsulated pneumococci, but express surface proteins unique to NESp. A chinchilla model of otitis media (OM) was used to determine the effect various pneumococcal mutations have on pathogenesis in both NESp and encapsulated pneumococci. Epithelial cell adhesion and invasion assays were used to examine the effects in relation to deletion of intrinsic genes or expression of novel genes. A mouse model of colonization was also utilized for comparison of various pneumococcal mutants. It was determined that pneumococcal surface protein K (PspK) and pneumolysin (Ply) affect NESp middle ear pathogenesis, but only PspK affected epithelial cell adhesion. Experiments in an OM model were done with encapsulated strains testing the importance of native virulence factors and treatment of OM. First, a triple deletion of the common virulence factors PspA, PspC, and Ply, (ΔPAC), from an encapsulated background abolished virulence in an OM model while a PspC mutant had detectable, but reduced amounts of recoverable bacteria compared to wildtype. Next, treatment of OM was effective when starting antibiotic treatment within 24 h with resolution by 48 h post-treatment. Expression of NESp-specific virulence factor PspK in an encapsulated strain has not been previously studied, and we showed significantly increased adhesion and invasion of human epithelial cells by pneumococci. Murine colonization was not significantly increased when an encapsulated strain expressed PspK, but colonization was increased when a capsule mutant expressed PspK. The ability of PspK expression to increase colonization in a capsule mutant despite no increase in adhesion can be attributed to other functions of PspK, such as sIgA binding or immune modulation. OM is a substantial economic burden, thus a better understanding of both encapsulated pneumococcal pathogenesis and the emerging pathogen NESp is necessary for effective prevention and treatment.
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Affiliation(s)
- Lance E Keller
- Department of Microbiology and Immunology, University of Mississippi Medical Center Jackson, MS, USA
| | - Jessica L Bradshaw
- Department of Microbiology and Immunology, University of Mississippi Medical Center Jackson, MS, USA
| | - Haley Pipkins
- Department of Microbiology and Immunology, University of Mississippi Medical Center Jackson, MS, USA
| | - Larry S McDaniel
- Department of Microbiology and Immunology, University of Mississippi Medical Center Jackson, MS, USA
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Pichichero ME, Khan MN, Xu Q. Next generation protein based Streptococcus pneumoniae vaccines. Hum Vaccin Immunother 2016; 12:194-205. [PMID: 26539741 PMCID: PMC4962723 DOI: 10.1080/21645515.2015.1052198] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 04/27/2015] [Accepted: 05/12/2015] [Indexed: 12/22/2022] Open
Abstract
All currently available Streptococcus pneumoniae (Spn) vaccines have limitations due to their capsular serotype composition. Both the 23-valent Spn polysaccharide vaccine (PPV) and 7, 10, or 13-valent Spn conjugate vaccines (PCV-7, 10, -13) are serotype-based vaccines and therefore they elicit only serotype-specific immunity. Emergence of replacement Spn strains expressing other serotypes has consistently occurred following introduction of capsular serotype based Spn vaccines. Furthermore, capsular polysaccharide vaccines are less effective in protection against non-bacteremic pneumonia and acute otitis media (AOM) than against invasive pneumococcal disease (IPD). These shortcomings of capsular polysaccharide-based Spn vaccines have created high interest in development of non-serotype specific protein-based vaccines that could be effective in preventing both IPD and non-IPD infections. This review discusses the progress to date on development of Spn protein vaccine candidates that are highly conserved by all Spn strains, are highly conserved, exhibit maximal antigenicity and minimal reactogenicity to replace or complement the current capsule-based vaccines. Key to development of a protein based Spn vaccine is an understanding of Spn pathogenesis. Based on pathogenesis, a protein-based Spn vaccine should include one or more ingredients that reduce NP colonization below a pathogenic inoculum. Elimination of all Spn colonization may not be achievable or even advisable. The level of expression of a target protein antigen during pathogenesis is another key to the success of protein based vaccines.. As with virtually all currently licensed vaccines, production of a serum antibody response in response to protein based vaccines is anticipated to provide protection from Spn infections. A significant advantage that protein vaccine formulations can offer over capsule based vaccination is their potential benefits associated with natural priming and boosting to all strains of Spn. One of the most universal and comprehensive approaches of identifying novel vaccine candidates is the investigation of human sera from different disease stages of natural infections. Antigens that are robustly reactive in preliminary human serum screening constitute a pathogen-specific antigenome. This strategy has identified a number of Spn protein vaccine candidates that are moving forward in human clinical trials.
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Affiliation(s)
| | - M Nadeem Khan
- Research Institute; Rochester General Hospital; Rochester, NY USA
| | - Qingfu Xu
- Research Institute; Rochester General Hospital; Rochester, NY USA
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Domenech M, Ruiz S, Moscoso M, García E. In vitro biofilm development of Streptococcus pneumoniae and formation of choline-binding protein-DNA complexes. ENVIRONMENTAL MICROBIOLOGY REPORTS 2015; 7:715-727. [PMID: 25950767 DOI: 10.1111/1758-2229.12295] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 04/08/2015] [Indexed: 06/04/2023]
Abstract
Extracellular deoxyribonucleic acid (eDNA) is an essential component of bacterial biofilm matrices, and is required in their formation and maintenance. Extracellular DNA binds to exopolysaccharides or extracellular proteins, affording biofilms greater structural integrity. Recently, we reported evidence of intercellular eDNA-LytC complexes in pneumococcal biofilms. The LytC lysozyme is a member of the choline-binding family of proteins (CBPs) located on the pneumococcal surface. The present work shows that other CBPs, i.e. LytA, LytB, Pce, PspC and CbpF, which have a pI between 5 and 6, can bind DNA in vitro. This process requires the presence of divalent cations other than Mg(2+). This DNA binding capacity of CBPs appears to be independent of their enzymatic activity and, at least in the case of LytA, does not require the choline-binding domain characteristic of CBPs. Positively charged, surface-exposed, 25 amino acid-long peptides derived from the catalytic domain of LytB, were also found capable of DNA binding through electrostatic interactions. Confocal laser scanning microcopy revealed the existence of cell-associated LytB-eDNA complexes in Streptococcus pneumoniae biofilms. These and other findings suggest that these surface-located proteins of S. pneumoniae could play roles of varying importance in the colonization and/or invasion of human host where different environmental conditions exist.
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Affiliation(s)
- Mirian Domenech
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, 28040, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Susana Ruiz
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Miriam Moscoso
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, 28040, Spain
| | - Ernesto García
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, 28040, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
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Shankar M, Mohapatra SS, Biswas S, Biswas I. Gene Regulation by the LiaSR Two-Component System in Streptococcus mutans. PLoS One 2015; 10:e0128083. [PMID: 26020679 PMCID: PMC4447274 DOI: 10.1371/journal.pone.0128083] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 04/23/2015] [Indexed: 12/22/2022] Open
Abstract
The LiaSR two-component signal transduction system regulates cellular responses to several environmental stresses, including those that induce cell envelope damages. Downstream regulons of the LiaSR system have been implicated in tolerance to acid, antibiotics and detergents. In the dental pathogen Streptococcus mutans, the LiaSR system is necessary for tolerance against acid, antibiotics, and cell wall damaging stresses during growth in the oral cavity. To understand the molecular mechanisms by which LiaSR regulates gene expression, we created a mutant LiaR in which the conserved aspartic acid residue (the phosphorylation site), was changed to alanine residue (D58A). As expected, the LiaR-D58A variant was unable to acquire the phosphate group and bind to target promoters. We also noted that the predicted LiaR-binding motif upstream of the lia operon does not appear to be well conserved. Consistent with this observation, we found that LiaR was unable to bind to the promoter region of lia; however, we showed that LiaR was able to bind to the promoters of SMU.753, SMU.2084 and SMU.1727. Based on sequence analysis and DNA binding studies we proposed a new 25-bp conserved motif essential for LiaR binding. Introducing alterations at fully conserved positions in the 25-bp motif affected LiaR binding, and the binding was dependent on the combination of positions that were altered. By scanning the S. mutans genome for the occurrence of the newly defined LiaR binding motif, we identified the promoter of hrcA (encoding a key regulator of the heat shock response) that contains a LiaR binding motif, and we showed that hrcA is negatively regulated by the LiaSR system. Taken together our results suggest a putative role of the LiaSR system in heat shock responses of S. mutans.
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Affiliation(s)
- Manoharan Shankar
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Saswat S. Mohapatra
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Saswati Biswas
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Indranil Biswas
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- * E-mail:
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Lee JY, Komatsu K, Lee BC, Miyata M, O'Neill Bohn A, Xu H, Yan C, Li JD. Vinpocetine inhibits Streptococcus pneumoniae-induced upregulation of mucin MUC5AC expression via induction of MKP-1 phosphatase in the pathogenesis of otitis media. THE JOURNAL OF IMMUNOLOGY 2015; 194:5990-8. [PMID: 25972475 DOI: 10.4049/jimmunol.1401489] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 04/19/2015] [Indexed: 02/04/2023]
Abstract
Mucin overproduction is a hallmark of otitis media (OM). Streptococcus pneumoniae is one of the most common bacterial pathogens causing OM. Mucin MUC5AC plays an important role in mucociliary clearance of bacterial pathogens. However, if uncontrolled, excessive mucus contributes significantly to conductive hearing loss. Currently, there is a lack of effective therapeutic agents that suppress mucus overproduction. In this study, we show that a currently existing antistroke drug, vinpocetine, a derivative of the alkaloid vincamine, inhibited S. pneumoniae-induced mucin MUC5AC upregulation in cultured middle ear epithelial cells and in the middle ear of mice. Moreover, vinpocetine inhibited MUC5AC upregulation by inhibiting the MAPK ERK pathway in an MKP-1-dependent manner. Importantly, ototopical administration of vinpocetine postinfection inhibited MUC5AC expression and middle ear inflammation induced by S. pneumoniae and reduced hearing loss and pneumococcal loads in a well-established mouse model of OM. Thus, these studies identified vinpocetine as a potential therapeutic agent for inhibiting mucus production in the pathogenesis of OM.
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Affiliation(s)
- Ji-Yun Lee
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Kensei Komatsu
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Byung-Cheol Lee
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Masanori Miyata
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Ashley O'Neill Bohn
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Haidong Xu
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
| | - Chen Yan
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester Medical Center, Rochester, NY 14642
| | - Jian-Dong Li
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303; and
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14
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Anderson D, Fakiola M, Hales BJ, Pennell CE, Thomas WR, Blackwell JM. Genome-wide association study of IgG1 responses to the choline-binding protein PspC of Streptococcus pneumoniae. Genes Immun 2015; 16:289-96. [PMID: 25928883 DOI: 10.1038/gene.2015.12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/12/2015] [Accepted: 03/04/2015] [Indexed: 11/09/2022]
Abstract
Streptococcus pneumoniae causes invasive pneumococcal disease. Delayed development of antibodies to S. pneumoniae in infancy is associated with the development of atopy and asthma. Pneumococcal surface protein C (PspC) is a vaccine candidate and variation in its choline-binding region is associated with invasive disease. This study examined 523 060 single-nucleotide polymorphisms in The Western Australian Pregnancy Cohort (Raine) Study to find loci influencing immunoglobulin G1 (IgG1) responses to PspC measured at age 14 years (n=1152). Genome-wide significance (top SNP rs9275596; P=3.1 × 10(-14)) was only observed at human leucocyte antigen (HLA). Imputed HLA amino-acid polymorphisms showed the strongest associations at positions DRB1 47 (P=3.2 × 10(-11)), 13SRG (P=9.8 × 10(-10)) and 11SP (P=9.8 × 10(-10)), and at DQA1 34 (P=6.4 × 10(-10)), DQB1 167R (P=9.3 × 10(-6)) and HLA-B 95 W (P=1.2 × 10(-9)). Conditional analyses showed independent contributions from DRB1 47 and DQB1 167R to the signal at rs9275596, supported by an omnibus test showing a strong signal for the haplotype DRB1_47_DQB1_167 (P=9.02 × 10(-15)). In silico analysis showed that DRB1 four-digit allele groups defined by DRB1 47F bind to a greater complexity of core 9-mer epitopes compared with DRB1 47Y, especially across repeats in the C-term choline-binding region. Consequent differences in CD4 T-cell help for IgG1 to PspC could have implications for vaccine design. Further analysis in other cohorts is merited.
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Affiliation(s)
- D Anderson
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia
| | - M Fakiola
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - B J Hales
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia
| | - C E Pennell
- School of Women's and Infants' Health, University of Western Australia, Perth, Australia
| | - W R Thomas
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia
| | - J M Blackwell
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia
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Jongerius I, Schuijt TJ, Mooi FR, Pinelli E. Complement evasion by Bordetella pertussis: implications for improving current vaccines. J Mol Med (Berl) 2015; 93:395-402. [PMID: 25686752 PMCID: PMC4366546 DOI: 10.1007/s00109-015-1259-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/19/2015] [Accepted: 01/27/2015] [Indexed: 12/17/2022]
Abstract
Bordetella pertussis causes whooping cough or pertussis, a highly contagious disease of the respiratory tract. Despite high vaccination coverage, reported cases of pertussis are rising worldwide and it has become clear that the current vaccines must be improved. In addition to the well-known protective role of antibodies and T cells during B. pertussis infection, innate immune responses such as the complement system play an essential role in B. pertussis killing. In order to evade this complement activation and colonize the human host, B. pertussis expresses several molecules that inhibit complement activation. Interestingly, one of the known complement evasion proteins, autotransporter Vag8, is highly expressed in the recently emerged B. pertussis isolates. Here, we describe the current knowledge on how B. pertussis evades complement-mediated killing. In addition, we compare this to complement evasion strategies used by other bacterial species. Finally, we discuss the consequences of complement evasion by B. pertussis on adaptive immunity and how identification of the bacterial molecules and the mechanisms involved in complement evasion might help improve pertussis vaccines.
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Affiliation(s)
- Ilse Jongerius
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
- Present Address: Department of Medical Microbiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Tim J. Schuijt
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
- Present Address: Department of Clinical Chemistry, Hematology and Immunology, Diakonessenhuis, Bosboomstraat 1, 3582 KE Utrecht, The Netherlands
| | - Frits R. Mooi
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Elena Pinelli
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
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