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Herrera AL, Van Hove C, Hanson M, Dale JB, Tweten RK, Huber VC, Diel D, Chaussee MS. Immunotherapy targeting the Streptococcus pyogenes M protein or streptolysin O to treat or prevent influenza A superinfection. PLoS One 2020; 15:e0235139. [PMID: 32574205 PMCID: PMC7310742 DOI: 10.1371/journal.pone.0235139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 06/09/2020] [Indexed: 12/12/2022] Open
Abstract
Viral infections complicated by a bacterial infection are typically referred to as coinfections or superinfections. Streptococcus pyogenes, the group A streptococcus (GAS), is not the most common bacteria associated with influenza A virus (IAV) superinfections but did cause significant mortality during the 2009 influenza pandemic even though all isolates are susceptible to penicillin. One approach to improve the outcome of these infections is to use passive immunization targeting GAS. To test this idea, we assessed the efficacy of passive immunotherapy using antisera against either the streptococcal M protein or streptolysin O (SLO) in a murine model of IAV-GAS superinfection. Prophylactic treatment of mice with antiserum to either SLO or the M protein decreased morbidity compared to mice treated with non-immune sera; however, neither significantly decreased mortality. Therapeutic use of antisera to SLO decreased morbidity compared to mice treated with non-immune sera but neither antisera significantly reduced mortality. Overall, the results suggest that further development of antibodies targeting the M protein or SLO may be a useful adjunct in the treatment of invasive GAS diseases, including IAV-GAS superinfections, which may be particularly important during influenza pandemics.
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Affiliation(s)
- Andrea L. Herrera
- Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, SD, United States of America
| | - Christopher Van Hove
- Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, SD, United States of America
| | - Mary Hanson
- Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, SD, United States of America
| | - James B. Dale
- Department of Medicine, Division of Infectious Diseases, University of Tennessee Health Science Center, Memphis, TN, United States of America
| | - Rodney K. Tweten
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America
| | - Victor C. Huber
- Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, SD, United States of America
| | - Diego Diel
- Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD, United States of America
| | - Michael S. Chaussee
- Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, SD, United States of America
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2
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Gao NJ, Al-Bassam MM, Poudel S, Wozniak JM, Gonzalez DJ, Olson J, Zengler K, Nizet V, Valderrama JA. Functional and Proteomic Analysis of Streptococcus pyogenes Virulence Upon Loss of Its Native Cas9 Nuclease. Front Microbiol 2019; 10:1967. [PMID: 31507572 PMCID: PMC6714885 DOI: 10.3389/fmicb.2019.01967] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 08/09/2019] [Indexed: 01/27/2023] Open
Abstract
The public health impact of Streptococcus pyogenes (group A Streptococcus, GAS) as a top 10 cause of infection-related mortality in humans contrasts with its benefit to biotechnology as the main natural source of Cas9 nuclease, the key component of the revolutionary CRISPR-Cas9 gene editing platform. Despite widespread knowledge acquired in the last decade on the molecular mechanisms by which GAS Cas9 achieves precise DNA targeting, the functions of Cas9 in the biology and pathogenesis of its native organism remain unknown. In this study, we generated an isogenic serotype M1 GAS mutant deficient in Cas9 protein and compared its behavior and phenotypes to the wild-type parent strain. Absence of Cas9 was linked to reduced GAS epithelial cell adherence, reduced growth in human whole blood ex vivo, and attenuation of virulence in a murine necrotizing skin infection model. Virulence defects of the GAS Δcas9 strain were explored through quantitative proteomic analysis, revealing a significant reduction in the abundance of key GAS virulence determinants. Similarly, deletion of cas9 affected the expression of several known virulence regulatory proteins, indicating that Cas9 impacts the global architecture of GAS gene regulation.
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Affiliation(s)
- Nina J Gao
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Mahmoud M Al-Bassam
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Saugat Poudel
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States.,Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
| | - Jacob M Wozniak
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States.,Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - David J Gonzalez
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States.,Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Joshua Olson
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Karsten Zengler
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States.,Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
| | - Victor Nizet
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - J Andrés Valderrama
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, United States
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3
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Streptolysin S induces mitochondrial damage and macrophage death through inhibiting degradation of glycogen synthase kinase-3β in Streptococcus pyogenes infection. Sci Rep 2019; 9:5371. [PMID: 30926881 PMCID: PMC6440947 DOI: 10.1038/s41598-019-41853-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 03/18/2019] [Indexed: 12/20/2022] Open
Abstract
Group A Streptococcus (GAS) infection is associated with a variety of human diseases. Previous studies indicate GAS infection leads to RAW264.7 cell death, but the mechanism is unclear. Here, analyzing the timing of reactive oxygen species (ROS) production and using mitochondrial ROS scavenger, we found the wild type GAS-induced RAW264.7 cell death was associated with mitochondrial ROS. The wild type GAS infection could activate glycogen synthase kinase-3β (GSK-3β). Inhibition of GSK-3β activity by lithium chloride or decreasing GSK-3β expression by lentivirus-mediated short hairpin RNA for GSK-3β could not only decrease the wild type GAS-induced mitochondrial ROS generation, mitochondria damage and cell death, but also reduced GAS intracellular replication. Streptolysin S (SLS), a GAS toxin, played the important role on GAS-induced macrophage death. Compared to the wild type GAS with its isogenic sagB mutant (SLS mutant)-infected macrophages, we found sagB mutant infection caused less mitochondrial ROS generation and cell death than those of the wild type GAS-infected ones. Furthermore, the sagB mutant, but not the wild type or the sagB-complementary mutant, could induce GSK-3β degradation via a proteasome-dependent pathway. These results suggest that a new mechanism of SLS-induced macrophage death was through inhibiting GSK-3β degradation and further enhancing mitochondrial damage.
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4
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Blocking Neuronal Signaling to Immune Cells Treats Streptococcal Invasive Infection. Cell 2018; 173:1083-1097.e22. [PMID: 29754819 DOI: 10.1016/j.cell.2018.04.006] [Citation(s) in RCA: 254] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 02/08/2018] [Accepted: 04/03/2018] [Indexed: 11/21/2022]
Abstract
The nervous system, the immune system, and microbial pathogens interact closely at barrier tissues. Here, we find that a bacterial pathogen, Streptococcus pyogenes, hijacks pain and neuronal regulation of the immune response to promote bacterial survival. Necrotizing fasciitis is a life-threatening soft tissue infection in which "pain is out of proportion" to early physical manifestations. We find that S. pyogenes, the leading cause of necrotizing fasciitis, secretes streptolysin S (SLS) to directly activate nociceptor neurons and produce pain during infection. Nociceptors, in turn, release the neuropeptide calcitonin gene-related peptide (CGRP) into infected tissues, which inhibits the recruitment of neutrophils and opsonophagocytic killing of S. pyogenes. Botulinum neurotoxin A and CGRP antagonism block neuron-mediated suppression of host defense, thereby preventing and treating S. pyogenes necrotizing infection. We conclude that targeting the peripheral nervous system and blocking neuro-immune communication is a promising strategy to treat highly invasive bacterial infections. VIDEO ABSTRACT.
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Mortensen R, Christensen D, Hansen LB, Christensen JP, Andersen P, Dietrich J. Local Th17/IgA immunity correlate with protection against intranasal infection with Streptococcus pyogenes. PLoS One 2017; 12:e0175707. [PMID: 28414746 PMCID: PMC5393599 DOI: 10.1371/journal.pone.0175707] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/30/2017] [Indexed: 01/11/2023] Open
Abstract
Streptococcus pyogenes (group A streptococcus, GAS) is responsible for a wide array of infections. Respiratory transmission via droplets is the most common mode of transmission but it may also infect the host via other routes such as lesions in the skin. To advance the development of a future vaccine against GAS, it is therefore important to investigate how protective immunity is related to the route of vaccine administration. To explore this, we examined whether a parenterally administered anti-GAS vaccine could protect against an intranasal GAS infection or if this would require locally primed immunity. We foundd that a parenteral CAF01 adjuvanted GAS vaccine offered no protection against intranasal infection despite inducing strong systemic Th1/Th17/IgG immunity that efficiently protected against an intraperitoneal GAS infection. However, the same vaccine administered via the intranasal route was able to induce protection against repeated intranasal GAS infections in a murine challenge model. The lack of intranasal protection induced by the parenteral vaccine correlated with a reduced mucosal recall response at the site of infection. Taken together, our results demonstrate that locally primed immunity is important for the defense against intranasal infection with Streptococcus pyogenes.
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Affiliation(s)
- Rasmus Mortensen
- Statens Serum Institut, Department of Infectious Disease Immunology, Copenhagen, Denmark
- University of Copenhagen, Department of Immunology and Microbiology, Copenhagen, Denmark
| | - Dennis Christensen
- Statens Serum Institut, Department of Infectious Disease Immunology, Copenhagen, Denmark
| | - Lasse Bøllehuus Hansen
- Rigshospitalet, Department of Growth and Reproduction, University of Copenhagen, Copenhagen, Denmark
| | | | - Peter Andersen
- Statens Serum Institut, Department of Infectious Disease Immunology, Copenhagen, Denmark
| | - Jes Dietrich
- Statens Serum Institut, Department of Infectious Disease Immunology, Copenhagen, Denmark
- * E-mail:
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6
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Kuo CF, Tsao N, Hsieh IC, Lin YS, Wu JJ, Hung YT. Immunization with a streptococcal multiple-epitope recombinant protein protects mice against invasive group A streptococcal infection. PLoS One 2017; 12:e0174464. [PMID: 28355251 PMCID: PMC5371370 DOI: 10.1371/journal.pone.0174464] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 03/09/2017] [Indexed: 12/11/2022] Open
Abstract
Streptococcus pyogenes (group A Streptococcus; GAS) causes clinical diseases, including pharyngitis, scarlet fever, impetigo, necrotizing fasciitis and streptococcal toxic shock syndrome. A number of group A streptococcus vaccine candidates have been developed, but only one 26-valent recombinant M protein vaccine has entered clinical trials. Differing from the design of a 26-valent recombinant M protein vaccine, we provide here a vaccination using the polyvalence epitope recombinant FSBM protein (rFSBM), which contains four different epitopes, including the fibronectin-binding repeats domain of streptococcal fibronectin binding protein Sfb1, the C-terminal immunogenic segment of streptolysin S, the C3-binding motif of streptococcal pyrogenic exotoxin B, and the C-terminal conserved segment of M protein. Vaccination with the rFSBM protein successfully prevented mortality and skin lesions caused by several emm strains of GAS infection. Anti-FSBM antibodies collected from the rFSBM-immunized mice were able to opsonize at least six emm strains and can neutralize the hemolytic activity of streptolysin S. Furthermore, the internalization of GAS into nonphagocytic cells is also reduced by anti-FSBM serum. These findings suggest that rFSBM can be applied as a vaccine candidate to prevent different emm strains of GAS infection.
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Affiliation(s)
- Chih-Feng Kuo
- Department of Nursing, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Nina Tsao
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - I-Chen Hsieh
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Yee-Shin Lin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan
| | - Yu-Ting Hung
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
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7
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Kuo CF, Tsao N, Cheng MH, Yang HC, Wang YC, Chen YP, Lin KJ. Application of the C3-binding motif of streptococcal pyrogenic exotoxin B to protect mice from invasive group a streptococcal infection. PLoS One 2015; 10:e0117268. [PMID: 25629609 PMCID: PMC4309557 DOI: 10.1371/journal.pone.0117268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/22/2014] [Indexed: 12/27/2022] Open
Abstract
Group A streptococcus (GAS) is an important human pathogen that produces several extracellular exotoxins to facilitate invasion and infection. Streptococcal pyrogenic exotoxin B (SPE B) has been demonstrated to be an important virulence factor of GAS. Our previous studies indicate that SPE B cleaves complement 3 (C3) and inhibits the activation of complement pathways. In this study, we constructed and expressed recombinant fragments of SPE B to examine the C3-binding site of SPE B. Using enzyme-linked immunosorbent assays and pull-down assays, we found that the C-terminal domain, containing amino-acid residues 345–398, of SPE B was the major binding site of human serum C3. We further identified a major, Ala376-Pro398, and a minor C3-binding motif, Gly346-Gly360, that both mediated the binding of C3 complement. Immunization with the C3-binding motifs protected mice against challenge with a lethal dose of non-invasive M49 strain GAS but not invasive M1 strains. To achieve higher efficiency against invasive M1 GAS infection, a combination of synthetic peptides derived from C-terminal epitope of streptolysin S (SLSpp) and from the major C3-binding motif of SPE B (PP6, Ala376-Pro398) was used to elicit specific immune response to those two important streptococcal exotoxins. Death rates and the severity of skin lesions decreased significantly in PP6/SLSpp-immunized mice that were infected with invasive M1 strains of GAS. These results indicate a combination of the C3-binding motif of SPE B and the protective epitope of SLS could be used as a subunit vaccine against invasive M1 strains group A streptococcal infection.
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Affiliation(s)
- Chih-Feng Kuo
- Department of Nursing, I-Shou University, Kaohsiung City, Taiwan
- * E-mail:
| | - Nina Tsao
- Department of Biological Science and Technology, I-Shou University, Kaohsiung City, Taiwan
| | - Miao-Hui Cheng
- Department of Biological Science and Technology, I-Shou University, Kaohsiung City, Taiwan
| | - Hsiu-Chen Yang
- Department of Biological Science and Technology, I-Shou University, Kaohsiung City, Taiwan
| | - Yu-Chieh Wang
- Department of Biological Science and Technology, I-Shou University, Kaohsiung City, Taiwan
| | - Ying-Pin Chen
- Department of Biological Science and Technology, I-Shou University, Kaohsiung City, Taiwan
| | - Kai-Jen Lin
- Department of Pathology, E-DA Hospital, Kaohsiung City, Taiwan
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8
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Olive C, Batzloff MR, Toth I. Lipid core peptide technology and group A streptococcal vaccine delivery. Expert Rev Vaccines 2014; 3:43-58. [PMID: 14761243 DOI: 10.1586/14760584.3.1.43] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The antiphagocytic surface M protein of group A streptococcus has been widely studied as the major candidate antigen for a vaccine to prevent group A streptococcus infection. Approaches that have proven to be effective in animal models include the use of multi-epitope vaccines incorporating highly variable amino terminal serotypic determinants, those based on the carboxy terminal conserved region and combination vaccines incorporating both serotypic and conserved region determinants of the M protein. The use of lipid core peptide technology is at the forefront of this research in the quest to develop a broad-strain protective vaccine that can be delivered via the mucosal route, stimulating mucosal and systemic immunity. This review aims to cover the various strategies and technologies that have been investigated with regard to group A streptococcus vaccine design and development.
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Affiliation(s)
- Colleen Olive
- Co-operative Research Centre for Vaccine Technology, The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland 4029, Australia.
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9
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Novel twin streptolysin S-like peptides encoded in the sag operon homologue of beta-hemolytic Streptococcus anginosus. J Bacteriol 2013; 195:1090-9. [PMID: 23292771 DOI: 10.1128/jb.01344-12] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus anginosus is a member of the anginosus group streptococci, which form part of the normal human oral flora. In contrast to the pyogenic group streptococci, our knowledge of the virulence factors of the anginosus group streptococci, including S. anginosus, is not sufficient to allow a clear understanding of the basis of their pathogenicity. Generally, hemolysins are thought to be important virulence factors in streptococcal infections. In the present study, a sag operon homologue was shown to be responsible for beta-hemolysis in S. anginosus strains by random gene knockout. Interestingly, contrary to pyogenic group streptococci, beta-hemolytic S. anginosus was shown to have two tandem sagA homologues, encoding streptolysin S (SLS)-like peptides, in the sag operon homologue. Gene deletion and complementation experiments revealed that both genes were functional, and these SLS-like peptides were essential for beta-hemolysis in beta-hemolytic S. anginosus. Furthermore, the amino acid sequence of these SLS-like peptides differed from that of the typical SLS of S. pyogenes, especially in their propeptide domain, and an amino acid residue indicated to be important for the cytolytic activity of SLS in S. pyogenes was deleted in both S. anginosus homologues. These data suggest that SLS-like peptides encoded by two sagA homologues in beta-hemolytic S. anginosus may be potential virulence factors with a different structure essential for hemolytic activity and/or the maturation process compared to the typical SLS present in pyogenic group streptococci.
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Abstract
Although the incidence of acute rheumatic fever and rheumatic heart disease has decreased significantly in regions of the world where antibiotics are easily accessible, there remains a high incidence in developing nations as well as in certain regions where there is a high incidence of genetic susceptibility. These diseases are a function of poverty, low socioeconomic status, and barriers to healthcare access, and it is in the developing world that a comprehensive prevention program is most critically needed. Development of group A streptococcal vaccines has been under investigation since the 1960s and 50 years later, we still have no vaccine. Factors that contribute to this lack of success include a potential risk for developing vaccine-induced rheumatic heart disease, as well as difficulties in covering the many serological subtypes of M protein, a virulence factor found on the surface of the bacterium. Yet, development of a successful vaccine program for prevention of group A streptococcal infection still offers the best chance for eradication of rheumatic fever in the twenty-first century. Other useful approaches include continuation of primary and secondary prevention with antibiotics and implementation of health care policies that provide patients with easy access to antibiotics. Improved living conditions and better hygiene are also critical to the prevention of the spread of group A streptococcus, especially in impoverished regions of the world. The purpose of this article is to discuss current and recent developments in the diagnosis, pathogenesis, and management of rheumatic fever and rheumatic heart disease.
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Affiliation(s)
- Christopher Chang
- Division of Allergy, Asthma and Immunology, Thomas Jefferson University, Nemours/A.I. Dupont Children's Hospital, 1600 Rockland Road, Wilmington, DE 19803, USA.
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11
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Molloy EM, Cotter PD, Hill C, Mitchell DA, Ross RP. Streptolysin S-like virulence factors: the continuing sagA. Nat Rev Microbiol 2011; 9:670-81. [PMID: 21822292 DOI: 10.1038/nrmicro2624] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Streptolysin S (SLS) is a potent cytolytic toxin and virulence factor that is produced by nearly all Streptococcus pyogenes strains. Despite a 100-year history of research on this toxin, it has only recently been established that SLS is just one of an extended family of post-translationally modified virulence factors (the SLS-like peptides) that are produced by some streptococci and other Gram-positive pathogens, such as Listeria monocytogenes and Clostridium botulinum. In this Review, we describe the identification, genetics, biochemistry and various functions of SLS. We also discuss the shared features of the virulence-associated SLS-like peptides, as well as their place within the rapidly expanding family of thiazole/oxazole-modified microcins (TOMMs).
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Affiliation(s)
- Evelyn M Molloy
- Department of Microbiology, University College Cork, Cork, Ireland
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Sumitomo T, Nakata M, Higashino M, Jin Y, Terao Y, Fujinaga Y, Kawabata S. Streptolysin S contributes to group A streptococcal translocation across an epithelial barrier. J Biol Chem 2010; 286:2750-61. [PMID: 21084306 DOI: 10.1074/jbc.m110.171504] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Group A Streptococcus pyogenes (GAS) is a human pathogen that causes local suppurative infections and severe invasive diseases. Systemic dissemination of GAS is initiated by bacterial penetration of the epithelial barrier of the pharynx or damaged skin. To gain insight into the mechanism by which GAS penetrates the epithelial barrier, we sought to identify both bacterial and host factors involved in the process. Screening of a transposon mutant library of a clinical GAS isolate recovered from an invasive episode allowed identification of streptolysin S (SLS) as a novel factor that facilitates the translocation of GAS. Of note, the wild type strain efficiently translocated across the epithelial monolayer, accompanied by a decrease in transepithelial electrical resistance and cleavage of transmembrane junctional proteins, including occludin and E-cadherin. Loss of integrity of intercellular junctions was inhibited after infection with a deletion mutant of the sagA gene encoding SLS, as compared with those infected with the wild type strain. Interestingly, following GAS infection, calpain was recruited to the plasma membrane along with E-cadherin. Moreover, bacterial translocation and destabilization of the junctions were partially inhibited by a pharmacological calpain inhibitor or genetic interference with calpain. Our data indicate a potential function of SLS that facilitates GAS invasion into deeper tissues via degradation of epithelial intercellular junctions in concert with the host cysteine protease calpain.
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Affiliation(s)
- Tomoko Sumitomo
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan
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13
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Lin A, Loughman JA, Zinselmeyer BH, Miller MJ, Caparon MG. Streptolysin S inhibits neutrophil recruitment during the early stages of Streptococcus pyogenes infection. Infect Immun 2009; 77:5190-201. [PMID: 19687200 PMCID: PMC2772533 DOI: 10.1128/iai.00420-09] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 05/24/2009] [Accepted: 08/10/2009] [Indexed: 11/20/2022] Open
Abstract
In contrast to infection of superficial tissues, Streptococcus pyogenes infection of deeper tissue can be associated with a significantly diminished inflammatory response, suggesting that this bacterium has the ability to both promote and suppress inflammation. To examine this, we analyzed the behavior of an S. pyogenes mutant deficient in expression of the cytolytic toxin streptolysin S (SLS-) and evaluated events that occur during the first few hours of infection by using several models including injection of zebrafish (adults, larvae, and embryos), a transepithelial polymorphonuclear leukocyte (PMN) migration assay, and two-photon microscopy of mice in vivo. In contrast to wild-type S. pyogenes, the SLS- mutant was associated with the robust recruitment of neutrophils and significantly reduced lethal myositis in adult zebrafish. Similarly, the mutant was attenuated in embryos in its ability to cause lethality. Infection of larva muscle allowed an analysis of inflammation in real time, which revealed that the mutant had recruited PMNs to the infection site. Analysis of transepithelial migration in vitro suggested that SLS inhibited the host cells' production of signals chemotactic for neutrophils, which contrasted with the proinflammatory effect of an unrelated cytolytic toxin, streptolysin O. Using two-photon microscopy of mice in vivo, we showed that the extravasation of neutrophils during infection with SLS- mutant bacteria was significantly accelerated compared to infection with wild-type S. pyogenes. Taken together, these data support a role for SLS in the inhibition of neutrophil recruitment during the early stages of S. pyogenes infection.
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Affiliation(s)
- Ada Lin
- Department of Pediatrics, Department of Pathology and Immunology, Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri 63110-1093
| | - Jennifer A. Loughman
- Department of Pediatrics, Department of Pathology and Immunology, Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri 63110-1093
| | - Bernd H. Zinselmeyer
- Department of Pediatrics, Department of Pathology and Immunology, Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri 63110-1093
| | - Mark J. Miller
- Department of Pediatrics, Department of Pathology and Immunology, Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri 63110-1093
| | - Michael G. Caparon
- Department of Pediatrics, Department of Pathology and Immunology, Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri 63110-1093
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14
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Dale JB. Current status of group A streptococcal vaccine development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 609:53-63. [PMID: 18193657 DOI: 10.1007/978-0-387-73960-1_5] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
We now have a much more detailed understanding of the molecular pathogenesis of GAS infections. These discoveries have led to the identification of several vaccine candidates which are in various stages of development. One of the leading candidate antigens is the surface M protein, which confers protection against infection in animal models. In addition, M antibodies in human serum correlate with protection against infection with the homologous serotype of GAS. Molecular techniques have been used to genetically engineer highly complex multivalent M protein-based vaccines that appear to be free of potentially harmful tissue crossreactive epitopes. A 26-valent vaccine has been shown to be well-tolerated and immunogenic in adult volunteers and is now being considered for pediatric trials, which is the primary target group for the vaccine. Ongoing efforts are now addressing the epidemiology of GAS infections in developing countries so that new vaccines can be designed to prevent the infections that may trigger ARF and RHD. Successful deployment of safe and effective vaccines to prevent GAS infections and their complications could potentially have a significant impact on the health of millions of people around the world.
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Affiliation(s)
- James B Dale
- University of Tennessee Health Science Center, Memphis 38104, USA.
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15
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Abstract
Necrotising fasciitis is a rare but life-threatening infectious disease emergency. Delays in diagnosis and treatment are common, and mortality rates often exceed 30%. Successful management of this disease requires high clinical suspicion and aggressive action. The mainstays of therapy include early and wide surgical debridement, antibiotics and supportive care, with prompt surgical intervention. Adjunctive modalities, such as protein synthesis inhibitors, hyperbaric oxygen and intravenous immunoglobulin, may have a role, but their effectiveness remains unproven. New rapid diagnostic tools are emerging that promise to revolutionize early detection of necrotising fasciitis. Research into the molecular microbiology, especially regarding group A streptococcus, are providing novel insights into the pathogenesis of necrotising soft tissue infections and identifying future targets for rationally designed interventions.
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16
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Young MH, Aronoff DM, Engleberg NC. Necrotizing fasciitis: pathogenesis and treatment. Expert Rev Anti Infect Ther 2006; 3:279-94. [PMID: 15918785 DOI: 10.1586/14787210.3.2.279] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Necrotizing fasciitis is a rapidly progressive, life-threatening infection and a true infectious disease emergency. Despite much clinical experience, the management of this disease remains suboptimal, with mortality rates remaining approximately 30%. Necrotizing fasciitis rarely presents with obvious signs and symptoms and delays in diagnosis enhance mortality. Therefore, successful patient care depends on the physician's acumen and index of suspicion. Prompt surgical debridement, intravenous antibiotics, fluid and electrolyte management, and analgesia are mainstays of therapy. Adjunctive clindamycin, hyperbaric oxygen therapy and intravenous immunoglobulin are frequently employed in the treatment of necrotizing fasciitis, but their efficacy has not been rigorously established. Improved understanding of the pathogenesis of necrotizing fasciitis has revealed new targets for rationally designed therapies to improve morbidity and mortality.
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Affiliation(s)
- Michael H Young
- Ann Arbor Veterans Affairs Hospital, Division of Infectious Diseases, Department of Internal Medicine, Ann Arbor, MI, USA.
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17
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Datta V, Myskowski SM, Kwinn LA, Chiem DN, Varki N, Kansal RG, Kotb M, Nizet V. Mutational analysis of the group A streptococcal operon encoding streptolysin S and its virulence role in invasive infection. Mol Microbiol 2005; 56:681-95. [PMID: 15819624 DOI: 10.1111/j.1365-2958.2005.04583.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pathogen group A Streptococcus (GAS) produces a wide spectrum of infections including necrotizing fasciitis (NF). Streptolysin S (SLS) produces the hallmark beta-haemolytic phenotype produced by GAS. The nine-gene GAS locus (sagA-sagI) resembling a bacteriocin biosynthetic operon is necessary and sufficient for SLS production. Using precise, in-frame allelic exchange mutagenesis and single-gene complementation, we show sagA, sagB, sagC, sagD, sagE, sagF and sagG are each individually required for SLS production, and that sagE may further serve an immunity function. Limited site-directed mutagenesis of specific amino acids in the SagA prepropeptide supports the designation of SLS as a bacteriocin-like toxin. No significant pleotrophic effects of sagA deletion were observed on M protein, capsule or cysteine protease production. In a murine model of NF, the SLS-negative M1T1 GAS mutant was markedly diminished in its ability to produce necrotic skin ulcers and spread to the systemic circulation. The SLS toxin impaired phagocytic clearance and promoted epithelial cell cytotoxicity, the latter phenotype being enhanced by the effects of M protein and streptolysin O. We conclude that all genetic components of the sag operon are required for expression of functional SLS, an important virulence factor in the pathogenesis of invasive M1T1 GAS infection.
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Affiliation(s)
- Vivekanand Datta
- Department of Pediatrics, Division of Infectious Diseases, University of California, San Diego, La Jolla, CA, USA
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18
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Abstract
The conventional, currently available vaccines, though quite successful, suffer from a few shortcomings which hamper future vaccine development. We present herewith some of the new approaches that are presently being pursued, including (1) the development of recombinant, or genetically engineered, vaccines which are based either on the expression of the relevant protective antigen and its formulation into vaccine, or the production of live vaccines, where an appropriate live vector (virus or bacterium) presents the foreign antigen. (2) The development of naked DNA vaccines that include the gene(s) coding for the relevant protective antigen(s). (3) Peptide vaccines that include defined B cell and T cell epitopes, either in a chemically synthesized molecule or in a synthetic recombinant construct. The efficacy of such vaccines is usually dependent on adequate presentation and delivery, namely, carrier/adjuvant technology. (4) Therapeutic vaccines, based on all of the above approaches, may be applied for chronic or long-term infections, or for noninfectious diseases including autoimmune diseases, various neurological disorders, allergy and cancer.
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Affiliation(s)
- Ruth Arnon
- Department of Immunology, The Weizmann Institute, PO Box 26, 76100 Rehovot, Israel.
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19
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Bisno AL, Brito MO, Collins CM. Molecular basis of group A streptococcal virulence. THE LANCET. INFECTIOUS DISEASES 2003; 3:191-200. [PMID: 12679262 DOI: 10.1016/s1473-3099(03)00576-0] [Citation(s) in RCA: 319] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The group A streptococcus (GAS) (Streptococcus pyogenes) is among the most common and versatile of human pathogens. It is responsible for a wide spectrum of human diseases, ranging from trivial to lethal. The advent of modern techniques of molecular biology has taught much about the organism's virulence, and the genomes of several GAS types have now been deciphered. Surface structures of GAS including a family of M proteins, the hyaluronic acid capsule, and fibronectin-binding proteins, allow the organism to adhere to, colonise, and invade human skin and mucus membranes under varying environmental conditions. M protein binds to complement control factors and other host proteins to prevent activation of the alternate complement pathway and thus evade phagocytosis and killing by polymorphonuclear leucocytes. Extracellular toxins, including superantigenic streptococcal pyrogenic exotoxins, contribute to tissue invasion and initiate the cytokine storm felt responsible for illnesses such as necrotising fasciitis and the highly lethal streptococcal toxic shock syndrome. Progress has been made in understanding the molecular epidemiology of acute rheumatic fever but less is understood about its basic pathogenesis. The improved understanding of GAS genetic regulation, structure, and function has opened exciting possibilities for developing safe and effective GAS vaccines. Studies directed towards achieving this long-sought goal are being aggressively pursued.
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Affiliation(s)
- A L Bisno
- Miami Veterans Affairs Medical Center, and the University of Miami School of Medicine, Miami, FL 33125, USA
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20
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Abstract
A zone of beta-hemolysis surrounding colonies on blood-agar media is a hallmark phenotypic feature of the pathogens group A Streptococcus (GAS) and group B Streptococcus (GBS). In each case, lysis of red blood cells reflects the action of a potent protein exotoxin. Although these toxins have been the subjects of numerous investigations over the years, their purification and molecular identification have proven elusive. These difficulties reflect the instability of hemolytic activity, as both toxins function only in the context of the bacterial surface or certain high molecular weight 'stabilizer' molecules. This review highlights the recent discoveries of two markedly distinct genetic loci, necessary and sufficient for the beta-hemolytic phenotypes of GAS and GBS, respectively. The generation of isogenic GAS and GBS beta-hemolysin-deficient mutants and their analysis using in vitro and in vivo model systems has shown that both toxins function as virulence factors in the pathogenesis of invasive infections.
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Affiliation(s)
- Victor Nizet
- Division of Pediatric Infectious Diseases, University of California, San Diego, 9500 Gilman Drive, MC 0672, La Jolla 92093, USA.
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21
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Fuller JD, Camus AC, Duncan CL, Nizet V, Bast DJ, Thune RL, Low DE, De Azavedo JCS. Identification of a streptolysin S-associated gene cluster and its role in the pathogenesis of Streptococcus iniae disease. Infect Immun 2002; 70:5730-9. [PMID: 12228303 PMCID: PMC128303 DOI: 10.1128/iai.70.10.5730-5739.2002] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus iniae causes meningoencephalitis and death in cultured fish species and soft-tissue infection in humans. We recently reported that S. iniae is responsible for local tissue necrosis and bacteremia in a murine subcutaneous infection model. The ability to cause bacteremia in this model is associated with a genetic profile unique to strains responsible for disease in fish and humans (J. D. Fuller, D. J. Bast, V. Nizet, D. E. Low, and J. C. S. de Azavedo, Infect. Immun. 69:1994-2000, 2001). S. iniae produces a cytolysin that confers a hemolytic phenotype on blood agar media. In this study, we characterized the genomic region responsible for S. iniae cytolysin production and assessed its contribution to virulence. Transposon (Tn917) mutant libraries of commensal and disease-associated S. iniae strains were generated and screened for loss of hemolytic activity. Analysis of two nonhemolytic mutants identified a chromosomal locus comprising 9 genes with 73% homology to the group A streptococcus (GAS) sag operon for streptolysin S (SLS) biosynthesis. Confirmation that the S. iniae cytolysin is a functional homologue of SLS was achieved by PCR ligation mutagenesis, complementation of an SLS-negative GAS mutant, and use of the SLS inhibitor trypan blue. SLS-negative sagB mutants were compared to their wild-type S. iniae parent strains in the murine model and in human whole-blood killing assays. These studies demonstrated that S. iniae SLS expression is required for local tissue necrosis but does not contribute to the establishment of bacteremia or to resistance to phagocytic clearance.
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Affiliation(s)
- Jeffrey D Fuller
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Ontario, Canada
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