1
|
Li S, Zhang W. Mapping the functional B-cell epitopes of Shigella invasion plasmid antigen D (IpaD). Appl Environ Microbiol 2024; 90:e0098824. [PMID: 39082807 PMCID: PMC11337796 DOI: 10.1128/aem.00988-24] [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: 05/17/2024] [Accepted: 07/17/2024] [Indexed: 08/22/2024] Open
Abstract
Shigella bacteria utilize the type III secretion system (T3SS) to invade host cells and establish local infection. Invasion plasmid antigen D (IpaD), a component of Shigella T3SS, has garnered extensive interest as a vaccine target, primarily due to its pivotal role in the Shigella invasion, immunogenic property, and a high degree of conservation across Shigella species and serotypes. Currently, we are developing an epitope- and structure-based multivalent vaccine against shigellosis and require functional epitope antigens of key Shigella virulence determinants including IpaD. However, individual IpaD B-cell epitopes, their contributions to the overall immunogenicity, and functional activities attributing to bacteria invasion have not been fully characterized. In this study, we predicted continuous B-cell epitopes in silico and fused each epitope to a carrier protein. Then, we immunized mice intramuscularly with each epitope fusion protein, examined the IpaD-specific antibody responses, and measured antibodies from each epitope fusion for the activity against Shigella invasion in vitro. Data showed that all epitope fusion proteins induced similar levels of anti-IpaD IgG antibodies in mice, and differences were noted for antibody inhibition activity against Shigella invasion. IpaD epitope 1 (SPGGNDGNSV), IpaD epitope 2 (LGGNGEVVLDNA), and IpaD epitope 5 (SPNNTNGSSTET) induced antibodies significantly better in inhibiting invasion from Shigella flexneri 2a, and epitopes 1 and 5 elicited antibodies more effectively at preventing invasion of Shigella sonnei. These results suggest that IpaD epitopes 1 and 5 can be the IpaD representative antigens for epitope-based polyvalent protein construction and protein-based cross-protective Shigella vaccine development.IMPORTANCEShigella is a leading cause of diarrhea in children younger than 5 years in developing countries (children's diarrhea) and continues to be a major threat to public health. No licensed vaccines are currently available against the heterogeneous Shigella species and serotype strains. Aiming to develop a cross-protective multivalent vaccine against shigellosis and dysentery, we applied novel multiepitope fusion antigen (MEFA) technology to construct a broadly immunogenic polyvalent protein antigen, by presenting functional epitopes of multiple Shigella virulence determinants on a backbone protein. The functional IpaD epitopes identified from this study will essentially allow us to construct an optimal polyvalent Shigella immunogen, leading to the development of a cross-protective vaccine against shigellosis (and dysentery) and the improvement of global health. In addition, identifying functional epitopes from heterogeneous virulence determinants and using them as antigenic representatives for the development of cross-protective multivalent vaccines can be applied generally in vaccine development.
Collapse
Affiliation(s)
- Siqi Li
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Weiping Zhang
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| |
Collapse
|
2
|
Haldar R, Dhar A, Ganguli D, Chakraborty S, Pal A, Banik G, Miyoshi SI, Das S. A candidate glycoconjugate vaccine induces protective antibodies in the serum and intestinal secretions, antibody recall response and memory T cells and protects against both typhoidal and non-typhoidal Salmonella serovars. Front Immunol 2024; 14:1304170. [PMID: 38264668 PMCID: PMC10804610 DOI: 10.3389/fimmu.2023.1304170] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 12/18/2023] [Indexed: 01/25/2024] Open
Abstract
Human Salmonella infections pose significant public health challenges globally, primarily due to low diagnostic yield of systemic infections, emerging and expanding antibiotic resistance of both the typhoidal and non-typhoidal Salmonella strains and the development of asymptomatic carrier state that functions as a reservoir of infection in the community. The limited long-term efficacy of the currently licensed typhoid vaccines, especially in smaller children and non-availability of vaccines against other Salmonella serovars necessitate active research towards developing a multivalent vaccine with wider coverage of protection against pathogenic Salmonella serovars. We had earlier reported immunogenicity and protective efficacy of a subunit vaccine containing a recombinant outer membrane protein (T2544) of Salmonella Typhi in a mouse model. This was achieved through the robust induction of serum IgG, mucosal secretory IgA and Salmonella-specific cytotoxic T cells as well as memory B and T cell response. Here, we report the development of a glycoconjugate vaccine, containing high molecular weight complexes of Salmonella Typhimurium O-specific polysaccharide (OSP) and recombinant T2544 that conferred simultaneous protection against S. Typhi, S. Paratyphi, S. Typhimurium and cross-protection against S. enteritidis in mice. Our findings corroborate with the published studies that suggested the potential of Salmonella OSP as a vaccine antigen. The role of serum antibodies in vaccine-mediated protection is suggested by rapid seroconversion with high titers of serum IgG and IgA, persistently elevated titers after primary immunization along with a strong antibody recall response with higher avidity serum IgG against both OSP and T2544 and significantly raised SBA titers of both primary and secondary antibodies against different Salmonella serovars. Elevated intestinal secretory IgA and bacterial motility inhibition by the secretory antibodies supported their role as well in vaccine-induced protection. Finally, robust induction of T effector memory response indicates long term efficacy of the candidate vaccine. The above findings coupled with protection of vaccinated animals against multiple clinical isolates confirm the suitability of OSP-rT2544 as a broad-spectrum candidate subunit vaccine against human infection due to typhoidal and non-typhoidal Salmonella serovars.
Collapse
Affiliation(s)
- Risha Haldar
- Division of Clinical Medicine, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Amlanjyoti Dhar
- Division of Molecular Biology and Genomics, International Institute of Innovation and Technology (I3T), Kolkata, India
| | - Debayan Ganguli
- Department of Infectious Diseases, Washington University School of Medicine at St. Louis, St. Louis, MO, United States
| | - Suparna Chakraborty
- Division of Clinical Medicine, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Ananda Pal
- Division of Clinical Medicine, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | | | - Shin-ichi Miyoshi
- Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Santasabuj Das
- Division of Clinical Medicine, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
- Division of Biological Science, Indian Council of Medical Research (ICMR)-National Institute of Occupational Health, Ahmedabad, India
| |
Collapse
|
3
|
Mosadegh S, Abtahi H, Amani J, Karizi SZ, Salmanian AH. Protective immunization against Enterohemorrhagic Escherichia coli and Shigella dysenteriae Type 1 by chitosan nanoparticle loaded with recombinant chimeric antigens comprising EIT and STX1B-IpaD. Microb Pathog 2023; 184:106344. [PMID: 37704060 DOI: 10.1016/j.micpath.2023.106344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/09/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023]
Abstract
Increasing evidence demonstrated that Enterohemorrhagic Escherichia coli (EHEC) and Shigella dysenteriae type 1 (S. dysenteriae1) are considered pathogens, that are connected with diarrhea and are still the greatest cause of death in children under the age of five years, worldwide. EHEC and S. dysenteriae 1 infections can be prevented and managed using a vaccination strategy against pathogen attachment stages. In this study, the chitosan nanostructures were loaded with recombinant EIT and STX1B-IpaD polypeptides. The immunogenic properties of this nano-vaccine candidate were investigated. The EIT and STX1B-IpaD recombinant proteins were heterologous expressed, purified, and confirmed by western blotting. The chitosan nanoparticles, were used to encapsulate the purified proteins. The immunogenicity of recombinant nano vaccine candidate, was examined in three groups of BalB/c mice by injection, oral delivery, and combination of oral-injection. ELISA and antibody titer, evaluated the humoral immune response. Finally, all three mice groups were challenged by two pathogens to test the ability of the nano-vaccine candidate to protect against bacterial infection. The Sereny test in guinea pigs was used to confirm the neutralizing effect of immune sera in controlling S. dysenteriae 1, infections. SDS-PAGE and western blotting, confirmed the presence and specificity of 63 and 27 kDa recombinant EIT and STX1B-IpaD, respectively. The results show that the nanoparticles containing recombinant proteins could stimulate the systemic and mucosal immune systems by producing IgG and IgA, respectively. The challenge test showed that, the candidate nano-vaccine could protect the animal model from bacterial infection. The combination of multiple recombinant proteins, carrying several epitopes and natural nanoparticles could evocate remarkable humoral and mucosal responses and improve the protection properties of synthetic antigens. Furthermore, compared with other available antigen delivery methods, using oral delivery as immune priming and injection as a booster method, could act as combinatorial methods to achieve a higher level of immunity. This approach could present an appropriate vaccine candidate against both EHEC and S. dysenteriae 1.
Collapse
Affiliation(s)
- Shadi Mosadegh
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Hamid Abtahi
- Molecular and Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
| | - Jafar Amani
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Shohreh Zare Karizi
- Department of Biology, Varamin Pishva Branch, Islamic Azad University, Pishva, Varamin, Iran
| | - Ali Hatef Salmanian
- Department of Agricultural Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
| |
Collapse
|
4
|
Zhou G, Zhao Y, Ma Q, Li Q, Wang S, Shi H. Manipulation of host immune defenses by effector proteins delivered from multiple secretion systems of Salmonella and its application in vaccine research. Front Immunol 2023; 14:1152017. [PMID: 37081875 PMCID: PMC10112668 DOI: 10.3389/fimmu.2023.1152017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/23/2023] [Indexed: 04/07/2023] Open
Abstract
Salmonella is an important zoonotic bacterial species and hazardous for the health of human beings and livestock globally. Depending on the host, Salmonella can cause diseases ranging from gastroenteritis to life-threatening systemic infection. In this review, we discuss the effector proteins used by Salmonella to evade or manipulate four different levels of host immune defenses: commensal flora, intestinal epithelial-mucosal barrier, innate and adaptive immunity. At present, Salmonella has evolved a variety of strategies against host defense mechanisms, among which various effector proteins delivered by the secretory systems play a key role. During its passage through the digestive system, Salmonella has to face the intact intestinal epithelial barrier as well as competition with commensal flora. After invasion of host cells, Salmonella manipulates inflammatory pathways, ubiquitination and autophagy processes with the help of effector proteins. Finally, Salmonella evades the adaptive immune system by interfering the migration of dendritic cells and interacting with T and B lymphocytes. In conclusion, Salmonella can manipulate multiple aspects of host defense to promote its replication in the host.
Collapse
Affiliation(s)
- Guodong Zhou
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Yuying Zhao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Qifeng Ma
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Quan Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Shifeng Wang
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
| | - Huoying Shi
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University (JIRLAAPS), Yangzhou, China
- *Correspondence: Huoying Shi,
| |
Collapse
|
5
|
Fathi J, Amani J, Nazarian S, Hadi N, Mirhosseini SA, Ranjbar R, Abianeh HS. Investigate the immunogenic and protective effect of trivalent chimeric protein containing IpaD-StxB-TolC antigens as a vaccine candidate against S. dysenteri and S. flexneri. Microb Pathog 2023; 178:106066. [PMID: 36924900 DOI: 10.1016/j.micpath.2023.106066] [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: 12/07/2022] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 03/17/2023]
Abstract
BACKGROUND s: Shigella spp. causes bloody diarrhea and leads to death, especially in children. Chimeric proteins containing virulence factors can prevent Shigella infection. The purpose of this study is to investigate the immunogenic and protective effect of trivalent chimeric protein containing IpaD-StxB-TolC antigens against shiga toxin, S. dysenteri and S. flexneri in vitro and in vivo conditions. METHODS Recombinant vector was transferred to E. coli BL21. The expression of the chimeric protein was confirmed by SDS PAGE and purified using the Ni-NTA column. Mice were immunized with recombinant protein and antibody titer was evaluated by ELISA. 10, 25 and 50 LD50 of Shiga toxin neutralization was evaluated in vitro (Vero cell line) and in vivo conditions. Also, the challenge of immunized mice with 10, 25 and 50 LD50 of S. dysentery and S. flexneri was done. RESULTS The expression and purification of the recombinant protein with 60.6 kDa was done. ELISA showed increased antibody titer against the chimeric protein. MTT assay indicated that 1/8000 dilution of the sera had a 51% of cell viability against the toxin in Vero cell line. The challenge of mice immunized with toxin showed that the mice had complete protection against 10 and 25 LD50 of toxin and had 40% survival against 50 LD50. Mice receiving 10 and 25 LD50 of S. dysenteri and S. flexneri had 100% protection and in 50 LD50 the survival rate was 60 and 50%, respectively. Organ burden showed that the amount of bacterial colonization in immunized mice was 1 × 104 CFU/mL, which was significantly different from the control group. CONCLUSION This study showed that chimeric proteins can create favorable immunogenicity in the host as vaccine candidates.
Collapse
Affiliation(s)
- Javad Fathi
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Jafar Amani
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
| | - Shahram Nazarian
- Department of Biological Sciences, Faculty of Science, Imam Hossein University, Tehran, Iran.
| | - Nahal Hadi
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Ali Mirhosseini
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Reza Ranjbar
- Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Hossein Samiei Abianeh
- Department of Medical Biotechnology and Nanotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
6
|
Song Y, Ma F, Sun M, Mu G, Tuo Y. The Chemical Structure Properties and Promoting Biofilm Activity of Exopolysaccharide Produced by Shigella flexneri. Front Microbiol 2022; 12:807397. [PMID: 35185832 PMCID: PMC8854994 DOI: 10.3389/fmicb.2021.807397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/23/2021] [Indexed: 11/17/2022] Open
Abstract
Shigella flexneri is a waterborne and foodborne pathogen that can damage human health. The exopolysaccharides (S-EPS) produced by S. flexneri CMCC51574 were found to promote biofilm formation and virulence. In this research, the crude S-EPS produced by S. flexneri CMCC51574 were separated into three main different fractions, S-EPS 1-1, S-EPS 2-1, and S-EPS 3-1. The structure of the S-ESP 2-1 was identified by FT-IR, ion chromatography analysis, methylation analysis, and NMR analysis. The main chain of S-EPS 2-1 was α-Manp-(1 → 3)-α-Manp-[(1 → 2,6)-α-Manp]15-[(1 → 2)-Manf-(1→]8; there were two branched-chain R1 and R2 with a ratio of 4:1, R1: α-Manp-(1 → 6)- and R2: α-Manp-(1 → 6)- Glc-(1 → 6)- were linked with (1 → 2,6)-α-Manp. It was found that S-EPS 2-1 exhibited the highest promoting effect on biofilm formation of S. flexneri. The S-EPS 2-1 was identified to interact with extracellular DNA (eDNA) of S. flexneri, indicating that the S-EPS 2-1 was the specific polysaccharide in the spatial structure of biofilm formation. Our research found the important role of S-EPS in S. flexneri biofilm formation, which will help us to understand the underlining mechanisms of the biofilm formation and find effective ways to prevent S. flexneri biofilm infection.
Collapse
Affiliation(s)
- Yinglong Song
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Fenglian Ma
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Mengying Sun
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Guangqing Mu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Dalian Probiotics Function Research Key Laboratory, Dalian Polytechnic University, Dalian, China
| | - Yanfeng Tuo
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- *Correspondence: Yanfeng Tuo,
| |
Collapse
|
7
|
Recent Progress in Shigella and Burkholderia pseudomallei Vaccines. Pathogens 2021; 10:pathogens10111353. [PMID: 34832508 PMCID: PMC8621228 DOI: 10.3390/pathogens10111353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 12/28/2022] Open
Abstract
Significant advancement has been made in the development of vaccines against bacterial pathogens. However, several roadblocks have been found during the evaluation of vaccines against intracellular bacterial pathogens. Therefore, new lessons could be learned from different vaccines developed against unrelated intracellular pathogens. Bacillary dysentery and melioidosis are important causes of morbidity and mortality in developing nations, which are caused by the intracellular bacteria Shigella and Burkholderia pseudomallei, respectively. Although the mechanisms of bacterial infection, dissemination, and route of infection do not provide clues about the commonalities of the pathogenic infectious processes of these bacteria, a wide variety of vaccine platforms recently evaluated suggest that in addition to the stimulation of antibodies, identifying protective antigens and inducing T cell responses are some additional required elements to induce effective protection. In this review, we perform a comparative evaluation of recent candidate vaccines used to combat these two infectious agents, emphasizing the common strategies that can help investigators advance effective and protective vaccines to clinical trials.
Collapse
|
8
|
Swietnicki W. Secretory System Components as Potential Prophylactic Targets for Bacterial Pathogens. Biomolecules 2021; 11:892. [PMID: 34203937 PMCID: PMC8232601 DOI: 10.3390/biom11060892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/13/2021] [Accepted: 06/14/2021] [Indexed: 01/18/2023] Open
Abstract
Bacterial secretory systems are essential for virulence in human pathogens. The systems have become a target of alternative antibacterial strategies based on small molecules and antibodies. Strategies to use components of the systems to design prophylactics have been less publicized despite vaccines being the preferred solution to dealing with bacterial infections. In the current review, strategies to design vaccines against selected pathogens are presented and connected to the biology of the system. The examples are given for Y. pestis, S. enterica, B. anthracis, S. flexneri, and other human pathogens, and discussed in terms of effectiveness and long-term protection.
Collapse
Affiliation(s)
- Wieslaw Swietnicki
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. R. Weigla 12, 53-114 Wroclaw, Poland
| |
Collapse
|
9
|
Sierocki R, Jneid B, Orsini Delgado ML, Plaisance M, Maillère B, Nozach H, Simon S. An antibody targeting type III secretion system induces broad protection against Salmonella and Shigella infections. PLoS Negl Trop Dis 2021; 15:e0009231. [PMID: 33711056 PMCID: PMC7990167 DOI: 10.1371/journal.pntd.0009231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/24/2021] [Accepted: 02/11/2021] [Indexed: 11/18/2022] Open
Abstract
Salmonella and Shigella bacteria are food- and waterborne pathogens that are responsible for enteric infections in humans and are still the major cause of morbidity and mortality in the emerging countries. The existence of multiple Salmonella and Shigella serotypes as well as the emergence of strains resistant to antibiotics requires the development of broadly protective therapies. Recently, the needle tip proteins of the type III secretion system of these bacteria were successfully utilized (SipD for Salmonella and IpaD for Shigella) as vaccine immunogens to provide good prophylactic cross-protection in murine models of infections. From these experiments, we have isolated a cross-protective monoclonal antibody directed against a conserved region of both proteins. Its conformational epitope determined by Deep Mutational Scanning is conserved among needle tip proteins of all pathogenic Shigella species and Salmonella serovars, and are well recognized by this antibody. Our study provides the first in vivo experimental evidence of the importance of this common region in the mechanism of virulence of Salmonella and Shigella and opens the way to the development of cross-protective therapeutic agents. Salmonella and Shigella are responsible for gastrointestinal diseases and continue to remain a serious health hazard in South and South-East Asia and African countries, even more with the new emergence of multi drug resistances. Developed vaccines are either not commercialized (for Shigella) or cover only a limited number of serotypes (for Salmonella). There is thus a crucial need to develop cross-protective therapies. By targeting proteins SipD and IpaD belonging respectively to the injectisome of Salmonella and Shigella and necessary to their virulence, we have shown that a monoclonal antibody (mAb) directed against a conserved common region of their apical part provides good cross-protection prophylactic efficacy. We have determined the region targeted by this mAb which could explain why it is conserved among Salmonella and Shigella bacteria.
Collapse
Affiliation(s)
- Raphaël Sierocki
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Bakhos Jneid
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Gif-sur-Yvette, France
| | - Maria Lucia Orsini Delgado
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Gif-sur-Yvette, France
| | - Marc Plaisance
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Gif-sur-Yvette, France
| | - Bernard Maillère
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Hervé Nozach
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Stéphanie Simon
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Gif-sur-Yvette, France
- * E-mail:
| |
Collapse
|