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Zhang Y, Li R, Li Q, Zhu Y, Yang X, Zhao D, Zong B. Orphan response regulator CovR plays positive regulative functions in the survivability and pathogenicity of Streptococcus suis serotype 2 isolated from a pig. BMC Vet Res 2023; 19:243. [PMID: 37990198 PMCID: PMC10664645 DOI: 10.1186/s12917-023-03808-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 11/09/2023] [Indexed: 11/23/2023] Open
Abstract
BACKGROUND Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen. Orphan response regulator CovR plays crucial regulative functions in the survivability and pathogenicity of S. suis 2. However, research on the CovR in S. suis 2 is limited. RESULTS In this study, the regulative functions of CovR in the survivability and pathogenicity were investigated in S. suis 2 isolated from a diseased pig. The deletion of CovR significantly weakened the survivability and pathogenicity of S. suis 2. Compared with the wild-type strain, ΔcovR showed slower growth rates and thinner capsular polysaccharides. Moreover, ΔcovR showed reduced adhesion and invasion to Hep-2 cells as well as anti-phagocytosis and anti-killing ability to 3D4 cells and anti-serum killing ability. In addition, the deletion of CovR significantly reduced the colonisation ability of S. suis 2 in mice. The survival rate of mice infected with ΔcovR was increased by 16.7% compared with that of mice infected with S. suis 2. Further, the deletion of CovR led to dramatic changes in metabolism-related pathways in S. suis 2, five of those, including fructose and mannose metabolism, glycerolipid metabolism, ABC transporters, amino sugar and nucleotide sugar metabolism and phosphotransferase system, were significantly down-regulated. CONCLUSIONS Based on the results, CovR plays positive regulative functions in the survivability and pathogenicity of S. suis 2 SC19 strain isolated from a pig.
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Affiliation(s)
- Yanyan Zhang
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Engineering Research Center of Feed Protein Resources on Agricultural By-products, Ministry of Education, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Rui Li
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Engineering Research Center of Feed Protein Resources on Agricultural By-products, Ministry of Education, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Qian Li
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Engineering Research Center of Feed Protein Resources on Agricultural By-products, Ministry of Education, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Yongwei Zhu
- Hunan International Scientific and Technological Cooperation Base of Brain Tumor Research, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaopei Yang
- Wuhan animal disease control center, Wuhan, Hubei, China
| | - Di Zhao
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Engineering Research Center of Feed Protein Resources on Agricultural By-products, Ministry of Education, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Bingbing Zong
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Engineering Research Center of Feed Protein Resources on Agricultural By-products, Ministry of Education, Wuhan Polytechnic University, Wuhan, 430023, China.
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Payen S, Roy D, Okura M, Segura M, Gottschalk M. Study of the Role of Lipoprotein Maturation Enzymes in the Pathogenesis of the Infection Caused by the Streptococcus suis Serotype 2 Sequence Type 25 North American Prototype Strain. Pathogens 2023; 12:1325. [PMID: 38003790 PMCID: PMC10675726 DOI: 10.3390/pathogens12111325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/26/2023] Open
Abstract
Streptococcus suis serotype 2 is an important swine bacterial pathogen causing sudden death, septic shock, and meningitis. However, serotype 2 strains are phenotypically and genotypically heterogeneous and composed of a multitude of sequence types (STs) whose distributions greatly vary worldwide. It has been previously shown that the lipoprotein (LPP) maturation enzymes diacylglyceryl transferase (Lgt) and signal peptidase (Lsp) significantly modulate the inflammatory host response and play a differential role in virulence depending on the genetic background of the strain. Differently from Eurasian ST1/ST7 strains, the capsular polysaccharide of a North American S. suis serotype 2 ST25 representative strain only partially masks sub-capsular domains and bacterial wall components. Thus, our hypothesis is that since LPPs would be more surface exposed in ST25 strains than in their ST1 or ST7 counterparts, the maturation enzymes would play a more important role in the pathogenesis of the infection caused by the North American strain. Using isogenic Δlgt and Δlsp mutants derived from the wild-type ST25 strain, our studies suggest that these enzymes do not seem to play a role in the interaction between S. suis and epithelial and endothelial cells, regardless of the genetics background of the strain used. However, a role in the formation of biofilms (also independently of the STs) has been demonstrated. Moreover, the involvement of LPP dendritic cell activation in vitro seems to be somehow more pronounced with the ST25 strain. Finally, the Lgt enzyme seems to play a more important role in the virulence of the ST25 strain. Although some differences between STs could be observed, our original hypothesis that LPPs would be significantly more important in ST25 strains due to a better bacterial surface exposition could not be confirmed.
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Affiliation(s)
- Servane Payen
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC J2S 2M2, Canada; (S.P.); (M.S.)
| | - David Roy
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada;
| | - Masatoshi Okura
- Division of Transboundary Animal Disease Research, National Institute of Animal Health, National Agriculture and Food Research Organization, Kagoshima 891-0105, Japan;
| | - Mariela Segura
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC J2S 2M2, Canada; (S.P.); (M.S.)
| | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC J2S 2M2, Canada; (S.P.); (M.S.)
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3
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Yang R, Wang J, Wang F, Zhang H, Tan C, Chen H, Wang X. Blood-Brain Barrier Integrity Damage in Bacterial Meningitis: The Underlying Link, Mechanisms, and Therapeutic Targets. Int J Mol Sci 2023; 24:ijms24032852. [PMID: 36769171 PMCID: PMC9918147 DOI: 10.3390/ijms24032852] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/26/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
Despite advances in supportive care and antimicrobial treatment, bacterial meningitis remains the most serious infection of the central nervous system (CNS) that poses a serious risk to life. This clinical dilemma is largely due to our insufficient knowledge of the pathology behind this disease. By controlling the entry of molecules into the CNS microenvironment, the blood-brain barrier (BBB), a highly selective cellular monolayer that is specific to the CNS's microvasculature, regulates communication between the CNS and the rest of the body. A defining feature of the pathogenesis of bacterial meningitis is the increase in BBB permeability. So far, several contributing factors for BBB disruption have been reported, including direct cellular damage brought on by bacterial virulence factors, as well as host-specific proteins or inflammatory pathways being activated. Recent studies have demonstrated that targeting pathological factors contributing to enhanced BBB permeability is an effective therapeutic complement to antimicrobial therapy for treating bacterial meningitis. Hence, understanding how these meningitis-causing pathogens affect the BBB permeability will provide novel perspectives for investigating bacterial meningitis's pathogenesis, prevention, and therapies. Here, we summarized the recent research progress on meningitis-causing pathogens disrupting the barrier function of BBB. This review provides handy information on BBB disruption by meningitis-causing pathogens, and helps design future research as well as develop potential combination therapies.
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Affiliation(s)
- Ruicheng Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Jundan Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Fen Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Huipeng Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Chen Tan
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture of the People’s Republic of China, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of the People’s Republic of China, Wuhan 430070, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture of the People’s Republic of China, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of the People’s Republic of China, Wuhan 430070, China
| | - Xiangru Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture of the People’s Republic of China, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of the People’s Republic of China, Wuhan 430070, China
- Correspondence:
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Xing X, Bi S, Fan X, Jin M, Liu W, Wang B. Intranasal Vaccination With Multiple Virulence Factors Promotes Mucosal Clearance of Streptococcus suis Across Serotypes and Protects Against Meningitis in Mice. J Infect Dis 2020; 220:1679-1687. [PMID: 31287878 DOI: 10.1093/infdis/jiz352] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/08/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Streptococcus suis is an emerging zoonotic agent. Its natural habitat is the tonsils, which are the main portals of S. suis entry into the bloodstream of pigs. The remarkable variability of the bacteria and complex pathogenic mechanisms make the development of a vaccine a difficult task. METHOD Five conserved virulence factors involved in critical events of S. suis pathogenesis were combined and used as an intranasal vaccine (V5). The effect of V5 was investigated with intranasal and systemic challenge models. RESULTS V5 induced antibody and T-cell responses at the mucosal site and systemically. The immunity promoted clearance of S. suis from the nasopharynx independent of S. suis serotypes and reduced lethality after systemic challenge with S. suis serotype 2. Moreover, mice that survived sepsis from intravenous infection developed meningitis, whereas none of these mice showed neuropathological symptoms after V5 receipt. CONCLUSION Intranasal immunization with multiple conserved virulence factors decreases S. suis colonization at the nasopharynx across serotypes and inhibits the dissemination of the bacteria in the host. The protective mucosal immunity effects would potentially reduce the S. suis reservoir and prevent S. suis disease in pigs.
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Affiliation(s)
- Xinxin Xing
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing
| | - Shuai Bi
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences
| | - Xin Fan
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences
| | - Meilin Jin
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Wenjun Liu
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences
| | - Beinan Wang
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences
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5
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Understanding the virulence of Streptococcus suis : A veterinary, medical, and economic challenge. Med Mal Infect 2018; 48:159-166. [DOI: 10.1016/j.medmal.2017.10.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 11/09/2016] [Accepted: 10/02/2017] [Indexed: 12/17/2022]
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6
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Aryl hydrocarbon receptor upregulates IL-1β expression in hCMEC/D3 human cerebral microvascular endothelial cells after TCDD exposure. Toxicol In Vitro 2017; 41:200-204. [DOI: 10.1016/j.tiv.2017.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 03/03/2017] [Accepted: 03/07/2017] [Indexed: 12/02/2022]
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7
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Segura M, Calzas C, Grenier D, Gottschalk M. Initial steps of the pathogenesis of the infection caused by Streptococcus suis: fighting against nonspecific defenses. FEBS Lett 2016; 590:3772-3799. [PMID: 27539145 DOI: 10.1002/1873-3468.12364] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 08/11/2016] [Accepted: 08/16/2016] [Indexed: 12/16/2022]
Abstract
Interactions between a bacterial pathogen and its potentially susceptible host are initiated with the colonization step. During respiratory/oral infection, the pathogens must compete with the normal microflora, resist defense mechanisms of the local mucosal immunity, and finally reach, adhere, and breach the mucosal epithelial cell barrier in order to induce invasive disease. This is the case during infection by the swine and zoonotic pathogen Streptococcus suis, which is able to counteract mucosal barriers to induce severe meningitis and sepsis in swine and in humans. The initial steps of the pathogenesis of S. suis infection has been a neglected area of research, overshadowed by studies on the systemic and central nervous phases of the disease. In this Review article, we provide for the first time, an exclusive focus on S. suis colonization and the potential mechanisms involved in S. suis establishment at the mucosa, as well as the mechanisms regulating mucosal barrier breakdown. The role of mucosal immunity is also addressed. Finally, we demystify the extensive list of putative adhesins and virulence factors reported to be involved in the initial steps of pathogenesis by S. suis.
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Affiliation(s)
- Mariela Segura
- Laboratory of Immunology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada.,Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - Cynthia Calzas
- Laboratory of Immunology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada.,Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Laboratory of Streptococcus suis, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Daniel Grenier
- Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de Recherche en Écologie Buccale (GREB), Faculté de Médecine Dentaire, Université Laval, Quebec City, Quebec, Canada
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Laboratory of Streptococcus suis, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
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8
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Tenenbaum T, Asmat TM, Seitz M, Schroten H, Schwerk C. Biological activities of suilysin: role in Streptococcus suis pathogenesis. Future Microbiol 2016; 11:941-54. [PMID: 27357518 DOI: 10.2217/fmb-2016-0028] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Streptococcus suis is an important swine and zoonotic pathogen equipped with several virulence factors. The pore-forming toxins are the most abundant bacterial toxins and classified as critical virulence (associated) factors of several pathogens. The role of suilysin (SLY), a pore-forming cholesterol-dependent cytolysin of S. suis, as a true virulence factor is under debate. Most of the bacterial toxins have been reported to modulate the host immune system to facilitate invasion and subsequent replication of bacteria within respective host cells. SLY has been demonstrated to play an important role in the pathogenesis of S. suis infection and inflammatory response in vitro and in vivo. This review highlights the contributions of SLY to the pathogenicity of S. suis. It will address its role during the development of S. suis meningitis in pigs, as well as humans, and discuss SLY as a potential vaccine candidate.
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Affiliation(s)
- Tobias Tenenbaum
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, Mannheim D-68167, Germany
| | - Tauseef M Asmat
- Center for Advanced Studies in Vaccinology and Biotechnology, Brewery Road, University of Balochistan, 87300 Quetta, Pakistan
| | - Maren Seitz
- Institute for Microbiology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, Hannover D-30173, Germany
| | - Horst Schroten
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, Mannheim D-68167, Germany
| | - Christian Schwerk
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, Mannheim D-68167, Germany
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9
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Auger JP, Christodoulides M, Segura M, Xu J, Gottschalk M. Interactions of Streptococcus suis serotype 2 with human meningeal cells and astrocytes. BMC Res Notes 2015; 8:607. [PMID: 26502903 PMCID: PMC4624383 DOI: 10.1186/s13104-015-1581-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 10/14/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Streptococcus suis serotype 2 is an important porcine pathogen and emerging zoonotic agent responsible for meningitis, of which different sequence types predominate worldwide. Though bacterial meningitis is defined as an exacerbated inflammation of the meninges, the underlying astrocytes of the glia limitans superficialis may also be implicated. However, the interactions between this pathogen and human meningeal cells or astrocytes remain unknown. Furthermore, the roles of well-described virulence factors (capsular polysaccharide, suilysin and cell wall modifications) in these interactions have yet to be studied. Consequently, the interactions between S. suis serotype 2 and human meningeal cells or astrocytes were evaluated for the first time in order to better understand their involvement during meningitis in humans. RESULTS Streptococcus suis serotype 2 adhered to human meningeal cells and astrocytes; invasion of meningeal cells was rare however, whereas invasion of astrocytes was generally more frequent. Regardless of the interaction or cell type, differences were not observed between sequence types. Though the capsular polysaccharide modulated the adhesion to and invasion of meningeal cells and astrocytes, the suilysin and cell wall modifications only influenced astrocyte invasion. Surprising, S. suis serotype 2 induced little or no inflammatory response from both cell types, but this absence of inflammatory response was probably not due to S. suis-induced cell death. CONCLUSIONS Though S. suis serotype 2 interacted with human meningeal cells and astrocytes, there was no correlation between sequence type and interaction. Consequently, the adhesion to and invasion of human meningeal cells and astrocytes are strain-specific characteristics. As such, the meningeal cells of the leptomeninges and the astrocytes of the glia limitans superficialis may not be directly implicated in the inflammatory response observed during meningitis in humans.
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Affiliation(s)
- Jean-Philippe Auger
- Faculty of Veterinary Medicine, Research Group on Infectious Diseases of Swine (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), University of Montreal, 3200 Sicotte Street, Saint-Hyacinthe, QC, J2S 2M2, Canada.
| | - Myron Christodoulides
- Neisseria Research Group, Molecular Microbiology, Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, UK.
| | - Mariela Segura
- Faculty of Veterinary Medicine, Research Group on Infectious Diseases of Swine (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), University of Montreal, 3200 Sicotte Street, Saint-Hyacinthe, QC, J2S 2M2, Canada.
| | - Jianguo Xu
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
| | - Marcelo Gottschalk
- Faculty of Veterinary Medicine, Research Group on Infectious Diseases of Swine (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), University of Montreal, 3200 Sicotte Street, Saint-Hyacinthe, QC, J2S 2M2, Canada.
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10
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Dando SJ, Mackay-Sim A, Norton R, Currie BJ, St John JA, Ekberg JAK, Batzloff M, Ulett GC, Beacham IR. Pathogens penetrating the central nervous system: infection pathways and the cellular and molecular mechanisms of invasion. Clin Microbiol Rev 2014; 27:691-726. [PMID: 25278572 PMCID: PMC4187632 DOI: 10.1128/cmr.00118-13] [Citation(s) in RCA: 273] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The brain is well protected against microbial invasion by cellular barriers, such as the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB). In addition, cells within the central nervous system (CNS) are capable of producing an immune response against invading pathogens. Nonetheless, a range of pathogenic microbes make their way to the CNS, and the resulting infections can cause significant morbidity and mortality. Bacteria, amoebae, fungi, and viruses are capable of CNS invasion, with the latter using axonal transport as a common route of infection. In this review, we compare the mechanisms by which bacterial pathogens reach the CNS and infect the brain. In particular, we focus on recent data regarding mechanisms of bacterial translocation from the nasal mucosa to the brain, which represents a little explored pathway of bacterial invasion but has been proposed as being particularly important in explaining how infection with Burkholderia pseudomallei can result in melioidosis encephalomyelitis.
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Affiliation(s)
- Samantha J Dando
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Alan Mackay-Sim
- Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
| | - Robert Norton
- Townsville Hospital, Townsville, Queensland, Australia
| | - Bart J Currie
- Menzies School of Health Research and Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - James A St John
- Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
| | - Jenny A K Ekberg
- Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Michael Batzloff
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Glen C Ulett
- School of Medical Science and Griffith Health Institute, Griffith University, Gold Coast, Queensland, Australia
| | - Ifor R Beacham
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
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11
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Role of capsule and suilysin in mucosal infection of complement-deficient mice with Streptococcus suis. Infect Immun 2014; 82:2460-71. [PMID: 24686060 DOI: 10.1128/iai.00080-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Virulent Streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. One objective of this study was to elucidate the function of complement in innate immune defense against S. suis. Experimental infection of wild-type (WT) and C3(-/-) mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal S. suis infection. S. suis WT but not an unencapsulated mutant caused mortality associated with meningitis and other pathologies in C3(-/-) mice. The capsule contributed also substantially to colonization of the upper respiratory tract. Experimental infection of C3(-/-) mice with a suilysin mutant indicated that suilysin expression facilitated an early disease onset and the pathogenesis of meningitis. Flow cytometric analysis revealed C3 antigen deposition on the surface of ca. 40% of S. suis WT bacteria after opsonization with naive WT mouse serum, although to a significantly lower intensity than on the unencapsulated mutant. Ex vivo multiplication in murine WT and C3(-/-) blood depended on capsule but not suilysin expression. Interestingly, S. suis invasion of inner organs was also detectable in C5aR(-/-) mice, suggesting that chemotaxis and activation of immune cells via the anaphylatoxin receptor C5aR is, in addition to opsonization, a further important function of the complement system in defense against mucosal S. suis infection. In conclusion, we unequivocally demonstrate here the importance of complement against mucosal S. suis serotype 2 infection and that the capsule of this pathogen is also involved in escape from complement-independent immunity.
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12
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Feng Y, Zhang H, Wu Z, Wang S, Cao M, Hu D, Wang C. Streptococcus suis infection: an emerging/reemerging challenge of bacterial infectious diseases? Virulence 2014; 5:477-97. [PMID: 24667807 PMCID: PMC4063810 DOI: 10.4161/viru.28595] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Streptococcus suis (S. suis) is a family of pathogenic gram-positive bacterial strains that represents a primary health problem in the swine industry worldwide. S. suis is also an emerging zoonotic pathogen that causes severe human infections clinically featuring with varied diseases/syndromes (such as meningitis, septicemia, and arthritis). Over the past few decades, continued efforts have made significant progress toward better understanding this zoonotic infectious entity, contributing in part to the elucidation of the molecular mechanism underlying its high pathogenicity. This review is aimed at presenting an updated overview of this pathogen from the perspective of molecular epidemiology, clinical diagnosis and typing, virulence mechanism, and protective antigens contributing to its zoonosis.
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Affiliation(s)
- Youjun Feng
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases & State Key Laboratory for Diagnosis and Treatment of Infectious Disease; First Affiliated Hospital; Zhejiang University School of Medicine; Hangzhou, Zhejiang, PR China; Department of Medical Microbiology and Parasitology; Zhejiang University School of Medicine; Hangzhou, Zhejiang, PR China
| | - Huimin Zhang
- University of Illinois at Urbana-Champaign (UIUC); Urbana, IL USA
| | - Zuowei Wu
- Department of Veterinary Microbiology and Preventive Medicine; Iowa State University; Ames, IA USA
| | - Shihua Wang
- College of Life Sciences; Fujian Agriculture and Forestry University; Fuzhou, Fujian, PR China
| | - Min Cao
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
| | - Dan Hu
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
| | - Changjun Wang
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
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13
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Characterization and proteome analysis of inosine 5-monophosphate dehydrogenase in epidemic Streptococcus suis serotype 2. Curr Microbiol 2014; 68:663-9. [PMID: 24458764 DOI: 10.1007/s00284-014-0527-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen that causes severe disease symptoms in pigs and humans. In the present study, we found one isogenic mutant lacking inosine 5-monophosphate dehydrogenase (IMPDH) ΔZY05719 was attenuated in pigs compared with the wild-type SS2 strain ZY05719. Comparative proteome analysis of the secreted proteins expression profiles between ZY05719 and ΔZY05719 allowed us to identify Triosephosphate isomerase (TPI) and glyceraldehyde phosphate dehydrogenase (GAPDH), which were down expressed in the absence of the IMPDH. Both of them are glycolytic enzymes participating in the glycolytic pathway. Compared with ZY05719, ΔZY05719 lost the ability of utilize mannose, which might relate to down expression of TPI and GAPDH. In addition, GAPDH is a well-known factor that involved in adhesion to host cells, and we demonstrated ability of adhesion to HEp-2 and PK15 by ΔZY05719 was significantly weakened, in contrast to ZY05719. The adhesion to host cells is the crucial step to cause infection for pathogen, and the reduction adhesion of ΔZY05719, to some extent illustrates the attenuated virulence of ΔZY05719.
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Fittipaldi N, Segura M, Grenier D, Gottschalk M. Virulence factors involved in the pathogenesis of the infection caused by the swine pathogen and zoonotic agent Streptococcus suis. Future Microbiol 2012; 7:259-79. [PMID: 22324994 DOI: 10.2217/fmb.11.149] [Citation(s) in RCA: 312] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Streptococcus suis is a major swine pathogen responsible for important economic losses to the swine industry worldwide. It is also an emerging zoonotic agent of meningitis and streptococcal toxic shock-like syndrome. Since the recent recognition of the high prevalence of S. suis human disease in southeast and east Asia, the interest of the scientific community in this pathogen has significantly increased. In the last few years, as a direct consequence of these intensified research efforts, large amounts of data on putative virulence factors have appeared in the literature. Although the presence of some proposed virulence factors does not necessarily define a S. suis strain as being virulent, several cell-associated or secreted factors are clearly important for the pathogenesis of the S. suis infection. In order to cause disease, S. suis must colonize the host, breach epithelial barriers, reach and survive in the bloodstream, invade different organs, and cause exaggerated inflammation. In this review, we discuss the potential contribution of different described S. suis virulence factors at each step of the pathogenesis of the infection. Finally, we briefly discuss other described virulence factors, virulence factor candidates and virulence markers for which a precise role at specific steps of the pathogenesis of the S. suis infection has not yet been clearly established.
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Affiliation(s)
- Nahuel Fittipaldi
- Groupe de Recherche sur les Maladies Infectieuses du Porc & Centre de Recherche en Infectiologie Porcine, Faculté de médecine vétérinaire, Université de Montréal, 3200 rue Sicotte, CP5000, St-Hyacinthe, Quebec, J2S 7C6, Canada
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The diagnostic value of cytokine and nitric oxide concentrations in cerebrospinal fluid for the differential diagnosis of meningitis. Adv Med Sci 2012; 57:142-7. [PMID: 22472468 DOI: 10.2478/v10039-012-0013-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE In several cases of meningitis routinely used diagnostic procedures are unable to identify the cause of this disease. The objective of the present study was to determine whether proinflammatory cytokine (tumour necrosis factor (TNF-α), interleukin-1β (IL-1β), interleukin-8 (IL-8)) and nitric oxide (NO) concentrations in the CSF are useful markers for the differential diagnosis of meningitis. MATERIAL AND METHODS Sixty-seven patients (42 patients with bacterial meningitis and 25 patients with viral meningitis) were included in the present study. In the investigated group, the TNF-α, IL-1β and IL-8 concentrations in the CSF samples collected on the day of admission were assessed. Furthermore, the NO concentrations were assessed in 23 patients. RESULTS The results revealed that the measurement of proinflammatory cytokines in CSF can aid in a differential diagnosis. In particular, a high concentration of TNF-α may be a sensitive and specific marker of a bacterial aetiology of the neuroinfection. In the present study, TNF-α concentrations greater than 75.8 pg/ml differentiated between bacterial and viral meningitis with 100% sensitivity and specificity. The NO concentration in the CSF was also significantly greater in patients with bacterial meningitis than in those with viral meningitis. CONCLUSIONS The assessment of TNF-α, IL-1β and IL-8 concentrations in the CSF is useful in the differential diagnosis of neuroinfection. Because many factors may influence NO production in the central nervous system (CNS), it is not clear whether NO values can be used for the differential diagnosis of meningitis, and further studies are required.
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Lecours MP, Gottschalk M, Houde M, Lemire P, Fittipaldi N, Segura M. Critical Role for Streptococcussuis Cell Wall Modifications and Suilysin in Resistance to Complement-Dependent Killing by Dendritic Cells. J Infect Dis 2011; 204:919-29. [DOI: 10.1093/infdis/jir415] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lecours MP, Segura M, Lachance C, Mussa T, Surprenant C, Montoya M, Gottschalk M. Characterization of porcine dendritic cell response to Streptococcus suis. Vet Res 2011; 42:72. [PMID: 21635729 PMCID: PMC3127767 DOI: 10.1186/1297-9716-42-72] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 06/02/2011] [Indexed: 01/08/2023] Open
Abstract
Streptococcus suis is a major swine pathogen and important zoonotic agent causing mainly septicemia and meningitis. However, the mechanisms involved in host innate and adaptive immune responses toward S. suis as well as the mechanisms used by S. suis to subvert these responses are unknown. Here, and for the first time, the ability of S. suis to interact with bone marrow-derived swine dendritic cells (DCs) was evaluated. In addition, the role of S. suis capsular polysaccharide in modulation of DC functions was also assessed. Well encapsulated S. suis was relatively resistant to phagocytosis, but it increased the relative expression of Toll-like receptors 2 and 6 and triggered the release of several cytokines by DCs, including IL-1β, IL-6, IL-8, IL-12p40 and TNF-α. The capsular polysaccharide was shown to interfere with DC phagocytosis; however, once internalized, S. suis was readily destroyed by DCs independently of the presence of the capsular polysaccharide. Cell wall components were mainly responsible for DC activation, since the capsular polysaccharide-negative mutant induced higher cytokine levels than the wild-type strain. The capsular polysaccharide also interfered with the expression of the co-stimulatory molecules CD80/86 and MHC-II on DCs. To conclude, our results show for the first time that S. suis interacts with swine origin DCs and suggest that these cells might play a role in the development of host innate and adaptive immunity during an infection with S. suis serotype 2.
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Affiliation(s)
- Marie-Pier Lecours
- Groupe de Recherche sur les Maladies Infectieuses du Porc and Centre de Recherche en Infectiologie Porcine, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, J2S 2M2, Canada.
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Bonifait L, Grenier D. The SspA subtilisin-like protease of Streptococcus suis triggers a pro-inflammatory response in macrophages through a non-proteolytic mechanism. BMC Microbiol 2011; 11:47. [PMID: 21362190 PMCID: PMC3058005 DOI: 10.1186/1471-2180-11-47] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 03/01/2011] [Indexed: 02/05/2023] Open
Abstract
Background Streptococcus suis is a major swine pathogen worldwide that causes meningitis, septicemia, arthritis, and endocarditis. Using animal models, a surface-associated subtilisin-like protease (SspA) has recently been shown to be an important virulence factor for S. suis. In this study, we hypothesized that the S. suis SspA subtilisin-like protease may modulate cytokine secretion by macrophages thus contributing to the pathogenic process of meningitis. Results Phorbol 12-myristate 13-acetate-differentiated U937 macrophages were stimulated with recombinant SspA prior to monitor cytokine secretion by ELISA. Our results indicated that the recombinant SspA was able to dose-dependently induce IL-1β, IL-6, TNF-α, CXCL8 and CCL5 secretion in macrophages. The heat-inactivated protease was still able to induce cytokine secretion suggesting a non-proteolytic mechanism of macrophage activation. Using specific kinase inhibitors, evidence were bought that cytokine secretion by macrophages stimulated with the recombinant SspA involves the mitogen-activated protein kinase signal transduction pathway. While stimulation of macrophages with low concentrations of recombinant SspA was associated to secretion of high amounts of CCL5, the use of recombinant SspA at a high concentration resulted in low amounts of CCL5 detected in the conditioned medium. This was found to be associated with a proteolytic degradation of CCL5 by SspA. The ability of SspA to induce cytokine secretion in macrophages was confirmed using a mutant of S. suis deficient in SspA expression. Conclusion In conclusion, this study identified a new mechanism by which the S. suis SspA may promote central nervous system inflammation associated with meningitis.
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Affiliation(s)
- Laetitia Bonifait
- Groupe de Recherche en Écologie Buccale, Faculté de médecine dentaire, Université Laval, Quebec City, Quebec, Canada
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Li R, Zhang A, Chen B, Teng L, Wang Y, Chen H, Jin M. Response of swine spleen to Streptococcus suis infection revealed by transcription analysis. BMC Genomics 2010; 11:556. [PMID: 20937098 PMCID: PMC3091705 DOI: 10.1186/1471-2164-11-556] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 10/11/2010] [Indexed: 11/20/2022] Open
Abstract
Astract
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Affiliation(s)
- Ran Li
- Unit of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, China
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Zeng X, Yuan Y, Wei Y, Jiang H, Zheng Y, Guo Z, Tang J, Yang R, Zhou D, Jiang Y. Microarray analysis of temperature-induced transcriptome of Streptococcus suis serotype 2. Vector Borne Zoonotic Dis 2010; 11:215-21. [PMID: 20795872 DOI: 10.1089/vbz.2009.0225] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Streptococcus suis serotype 2 (S. suis S2) is able to cause human infections ranging from superficial wounded skin infections to severe invasive infections such as meningitis and streptococcal toxic shock-like syndrome. During its infection cycle, S. suis S2 must acclimatize itself to temperature shift. Herein, a whole-genome DNA microarray was used to investigate the global transcriptional regulation of an invasive strain of S. suis S2 grown to late-exponential phase at 29°C or 40°C relative to 37°C. The differentially regulated genes that were detected included those encoding virulence factors, antigenic proteins, ATP-binding-cassette transporters, and proteins of unknown functions. Our data provided a global profile of gene transcription induced by temperature alteration and shed light on some unforeseen lines for further pathogenesis investigation.
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Affiliation(s)
- Xiaotao Zeng
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing, China
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Cytokine signaling in the human brain capillary endothelial cell line hCMEC/D3. Brain Res 2010; 1354:15-22. [PMID: 20692239 DOI: 10.1016/j.brainres.2010.07.077] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 07/21/2010] [Accepted: 07/22/2010] [Indexed: 10/19/2022]
Abstract
Brain microvascular endothelial cells are part of the blood-brain barrier and participate actively in immunological processes including cytokine-mediated inflammatory reactions. Using the human brain capillary endothelial cell line hCMEC/D3, activation of JAK/STAT signaling pathways were studied in response to stimulation by cytokines. The phenotype of hCMEC/D3 cells was confirmed by flow cytometry analysis of cell adhesion factors (cluster of differentiation molecules CD31 and CD34) and the von Willebrand factor endothelial marker was detected by immunofluorescence. Strong STAT1, STAT6 and STAT3 activation was observed in response to interferon-gamma (IFN-gamma), interleukin 4 (IL-4) and interleukin 6 (IL-6), respectively. Nuclear translocation of phosphorylated STAT proteins was visualized by confocal microscopy. Treatment of hCMEC/D3 cells with IFN-gamma resulted in interferon-induced upregulation of major histocompatibility complex (MHC) class I within 48h. Interferon-alpha (IFN-alpha) did not activate STAT1 or STAT3 nor did it induce MHC class I upregulation. Therefore, hCMEC/D3 cells were judged to be non-responsive to IFN-alpha. We also observed that hCMEC/D3 cells exhibit functional expression of alternative cytokine signal transduction pathways (i.e. TNF-alpha mediated activation of NF-kappaB). Together these results indicate that human blood-brain barrier hCMEC/D3 cells are responsive towards stimulation with various cytokines. We conclude that this unique cell line can be used to explore in vitro human blood-brain barrier functionality under proinflammatory conditions.
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Wu Z, Zhang W, Lu Y, Lu C. Transcriptome profiling of zebrafish infected with Streptococcus suis. Microb Pathog 2010; 48:178-87. [DOI: 10.1016/j.micpath.2010.02.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 02/23/2010] [Accepted: 02/25/2010] [Indexed: 10/19/2022]
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Gottschalk M, Xu J, Calzas C, Segura M. Streptococcus suis: a new emerging or an old neglected zoonotic pathogen? Future Microbiol 2010; 5:371-91. [DOI: 10.2217/fmb.10.2] [Citation(s) in RCA: 318] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Infections caused by Streptococcus suis are considered a global and an economical problem in the swine industry. Moreover, S. suis is an agent of zoonosis that afflicts people in close contact with infected pigs or pork-derived products. Although sporadic cases of S. suis infections in humans (mainly meningitis) have been reported during the last 40 years, a large outbreak due to this pathogen emerged in the summer of 2005 in China. The severity of the infection in humans during the outbreak, such as a shorter incubation time, more rapid disease progression and higher rate of mortality, attracted a lot of attention from the scientific community and the general press. In fact, the number of publications on S. suis (including the number of reported human cases) has significantly increased during recent years. In this article we critically review the present knowledge on S. suis infection in humans, we discuss the hypotheses that may explain the 2005 outbreak and the repercussion of such an episode on the scientific community.
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Affiliation(s)
- Marcelo Gottschalk
- Streptococcus suis Research Laboratory & International Reference Laboratory for S. suis Serotyping, Faculté de Médecine Vétérinaire, Département de Pathologie et Microbiologie, Université de Montréal, CP 5000, St-Hyacinthe, Québec, Canada
| | - Jianguo Xu
- State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Communicable Diseases Control and Prevention, 155 Changbai Road, Changping Disrict, Beijing 102206, People’s Republic of China
| | - Cynthia Calzas
- Laboratory of Immunology & Streptococcus suis Research Laboratory, Faculté de Médecine Vétérinaire, Département de Pathologie et Microbiologie, Université de Montréal, CP 5000, St-Hyacinthe, Québec, Canada
| | - Mariela Segura
- Laboratory of Immunology, Faculté de Médecine Vétérinaire, Département de Pathologie et Microbiologie, Université de Montréal, CP 5000, St-Hyacinthe, Québec, Canada
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