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Abele TJ, Billman ZP, Harvest CK, Bryan AK, Larson HN, Coers J, Miao EA. Overexpression of T3SS translocation signals in Salmonella causes delayed attenuation. Infect Immun 2024; 92:e0032923. [PMID: 38084951 PMCID: PMC10790824 DOI: 10.1128/iai.00329-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 11/21/2023] [Indexed: 01/17/2024] Open
Abstract
Engineering pathogens is a useful method for discovering new details of microbial pathogenesis and host defense. However, engineering can result in off-target effects. We previously engineered Salmonella enterica serovar Typhimurium to overexpress the secretion signal of the type 3 secretion system effector SspH1 fused with domains of other proteins as cargo. Such engineering had no virulence cost to the bacteria for the first 48 hours post infection in mice. Here, we show that after 48 hours, the engineered bacteria manifest an attenuation that correlates with the quantity of the SspH1 translocation signal expressed. In IFN-γ-deficient mice, this attenuation was weakened. Conversely, the attenuation was accelerated in the context of a pre-existing infection. We speculate that inflammatory signals change aspects of the target cell's physiology, which makes host cells less permissive to S. Typhimurium infection. This increased degree of difficulty requires the bacteria to utilize its T3SS at peak efficiency, which can be disrupted by engineered effectors.
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Affiliation(s)
- Taylor J. Abele
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Pathology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Zachary P. Billman
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Carissa K. Harvest
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Alexia K. Bryan
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Biomedical Engineering, Duke University Pratt School of Engineering, Durham, North Carolina, USA
| | - Heather N. Larson
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Pathology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Jörn Coers
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Edward A. Miao
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Pathology, Duke University School of Medicine, Durham, North Carolina, USA
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2
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Harrell JE, Hahn MM, D'Souza SJ, Vasicek EM, Sandala JL, Gunn JS, McLachlan JB. Salmonella Biofilm Formation, Chronic Infection, and Immunity Within the Intestine and Hepatobiliary Tract. Front Cell Infect Microbiol 2021; 10:624622. [PMID: 33604308 PMCID: PMC7885405 DOI: 10.3389/fcimb.2020.624622] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022] Open
Abstract
Within the species of Salmonella enterica, there is significant diversity represented among the numerous subspecies and serovars. Collectively, these account for microbes with variable host ranges, from common plant and animal colonizers to extremely pathogenic and human-specific serovars. Despite these differences, many Salmonella species find commonality in the ability to form biofilms and the ability to cause acute, latent, or chronic disease. The exact outcome of infection depends on many factors such as the growth state of Salmonella, the environmental conditions encountered at the time of infection, as well as the infected host and immune response elicited. Here, we review the numerous biofilm lifestyles of Salmonella (on biotic and abiotic surfaces) and how the production of extracellular polymeric substances not only enhances long-term persistence outside the host but also is an essential function in chronic human infections. Furthermore, careful consideration is made for the events during initial infection that allow for gut transcytosis which, in conjunction with host immune functions, often determine the progression of disease. Both typhoidal and non-typhoidal salmonellae can cause chronic and/or secondary infections, thus the adaptive immune responses to both types of bacteria are discussed with particular attention to the differences between Salmonella Typhi, Salmonella Typhimurium, and invasive non-typhoidal Salmonella that can result in differential immune responses. Finally, while strides have been made in our understanding of immunity to Salmonella in the lymphoid organs, fewer definitive studies exist for intestinal and hepatobiliary immunity. By examining our current knowledge and what remains to be determined, we provide insight into new directions in the field of Salmonella immunity, particularly as it relates to chronic infection.
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Affiliation(s)
- Jaikin E Harrell
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Mark M Hahn
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Shaina J D'Souza
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States
| | - Erin M Vasicek
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Jenna L Sandala
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - John S Gunn
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States.,Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - James B McLachlan
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, United States
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Hotinger JA, May AE. Antibodies Inhibiting the Type III Secretion System of Gram-Negative Pathogenic Bacteria. Antibodies (Basel) 2020; 9:antib9030035. [PMID: 32726928 PMCID: PMC7551047 DOI: 10.3390/antib9030035] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/16/2020] [Accepted: 07/22/2020] [Indexed: 12/11/2022] Open
Abstract
Pathogenic bacteria are a global health threat, with over 2 million infections caused by Gram-negative bacteria every year in the United States. This problem is exacerbated by the increase in resistance to common antibiotics that are routinely used to treat these infections, creating an urgent need for innovative ways to treat and prevent virulence caused by these pathogens. Many Gram-negative pathogenic bacteria use a type III secretion system (T3SS) to inject toxins and other effector proteins directly into host cells. The T3SS has become a popular anti-virulence target because it is required for pathogenesis and knockouts have attenuated virulence. It is also not required for survival, which should result in less selective pressure for resistance formation against T3SS inhibitors. In this review, we will highlight selected examples of direct antibody immunizations and the use of antibodies in immunotherapy treatments that target the bacterial T3SS. These examples include antibodies targeting the T3SS of Pseudomonas aeruginosa, Yersinia pestis, Escherichia coli, Salmonella enterica, Shigella spp., and Chlamydia trachomatis.
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Brucella Peptide Cross-Reactive Major Histocompatibility Complex Class I Presentation Activates SIINFEKL-Specific T Cell Receptor-Expressing T Cells. Infect Immun 2018; 86:IAI.00281-18. [PMID: 29735518 PMCID: PMC6013681 DOI: 10.1128/iai.00281-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 04/25/2018] [Indexed: 12/23/2022] Open
Abstract
Brucella spp. are intracellular pathogenic bacteria remarkable in their ability to escape immune surveillance and therefore inflict a state of chronic disease within the host. To enable further immune response studies, Brucella was engineered to express the well-characterized chicken ovalbumin (OVA). Surprisingly, we found that CD8 T cells bearing T cell receptors (TCR) nominally specific for the OVA peptide SIINFEKL (OT-1) reacted to parental Brucella-infected targets as well as OVA-expressing Brucella variants in cytotoxicity assays. Furthermore, splenocytes from Brucella-immunized mice produced gamma interferon (IFN-γ) and exhibited cytotoxicity in response to SIINFEKL-pulsed target cells.To determine if the SIINFEKL-reactive OT-1 TCR could be cross-reacting to Brucella peptides, we searched the Brucella proteome using an algorithm to generate a list of near-neighbor nonamer peptides that would bind to H2Kb. Selecting five Brucella peptide candidates, along with controls, we verified that several of these peptides mimicked SIINFEKL, resulting in T cell activation through the “SIINFEKL-specific” TCR. Activation was dependent on peptide concentration as well as sequence. Our results underscore the complexity and ubiquity of cross-reactivity in T cell recognition. This cross-reactivity may enable microbes such as Brucella to escape immune surveillance by presenting peptides similar to those of the host and may also lead to the activation of autoreactive T cells.
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Hu M, Zhao W, Gao W, Li W, Meng C, Yan Q, Wang Y, Zhou X, Geng S, Pan Z, Cui G, Jiao X. Recombinant Salmonella expressing SspH2-EscI fusion protein limits its colonization in mice. BMC Immunol 2017; 18:21. [PMID: 28468643 PMCID: PMC5415771 DOI: 10.1186/s12865-017-0203-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 04/24/2017] [Indexed: 12/20/2022] Open
Abstract
Background Activation of inflammasome contributes to the clearance of intracellular bacteria. C-terminus of E. coli EscI protein can activate NLRC4 (NLR family, CARD domain containing-4) inflammasome in macrophages. The purpose of this study was to determine if activation of NLRC4 inflammasome by EscI can reduce the colonization of Salmonella in mice. Results A recombinant S. typhimurium strain expressing fusion protein of the N-terminal SspH2 (a Salmonella type III secretion system 2 effector) and C-terminal EscI was constructed and designated as X4550(pYA3334-SspH2-EscI). In vitro assay showed that X4550(pYA3334-SspH2-EscI) significantly enhanced IL-1β and IL-18 secretion (P < 0.05) and pyroptotic cell death of mouse peritoneal macrophages, compared with those infected with control strain, X4550(pYA3334-SspH2). In vivo studies showed that colonization of X4550(pYA3334-SspH2-EscI) in both spleen and liver were significantly lower than that of X4550(pYA3334-SspH2) (P < 0.05). The bacterial counts of X4550(pYA3334-SspH2-EscI) in mice decreased, while those of X4550(pYA3334-SspH2) increased over the time after infection. Additionally, X4550(pYA3334-SspH2-EscI) induced a less pathological alteration in spleen and liver than X4550(pYA3334-SspH2). Conclusion Fusion protein SspH2-EscI may be translocated into macrophages and activate NLRC4 inflammasome, which limits Salmonella colonization in spleen and liver of mice.
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Affiliation(s)
- Maozhi Hu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China. .,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China.
| | - Weixin Zhao
- College of Tourism & Cuisine (College of Food Science and Engineering), Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Wei Gao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Wenhua Li
- College of Tourism & Cuisine (College of Food Science and Engineering), Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Chuang Meng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Qiuxiang Yan
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Yuyang Wang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Xiaohui Zhou
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China.,Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, 06269-3089, CT, USA
| | - Shizhong Geng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Zhiming Pan
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Guiyou Cui
- College of Tourism & Cuisine (College of Food Science and Engineering), Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Xinan Jiao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China. .,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, Jiangsu, China.
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Kamble NM, Nandre RM, Lee JH. Inhibition of Salmonella-induced apoptosis as a marker of the protective efficacy of virulence gene-deleted live attenuated vaccine. Vet Immunol Immunopathol 2015; 169:96-101. [PMID: 26651227 DOI: 10.1016/j.vetimm.2015.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/04/2015] [Accepted: 11/09/2015] [Indexed: 01/26/2023]
Abstract
Vaccination is one of the best protection strategies against Salmonella infection in humans and chickens. Salmonella bacteria must induce apoptosis prior to initiating infection, pathogenesis and evasion of host immune responses. In this study, we evaluated the efficacy of vaccinating chickens against Salmonella Enteritidis (SE) using a vaccine candidate strain (JOL919), constructed by deleting the lon and cpxR genes from a wild-type SE using an allelic exchange method. In present study day old chickens were inoculated with 1×10(7)cfu (colony forming unit) of JOL919 per os. We measured cell-mediated immunity, protective efficacy and extent of apoptosis induction in splenocytes. Seven days post-immunization, the number of CD3+CD4+ and CD3+ CD8+ T cells was significantly higher in the immunized group compared to the control group, indicating a significant augmentation of systemic immune response. The internal organs of chickens immunized with JOL919 had a significantly lower challenge-strain recovery, indicating effective protection and clearance of the challenge strain. Post-challenge, the number of apoptotic cells in the immunized group was significantly lower than in the control group. Additionally, AV/PI (Annexin V/propidium iodide) staining was performed to differentiate between apoptotic cells and necrotic cells, which corroborated TUNEL-assay (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling) results. The proportions of AV+/PI- and AV+/PI+ cells, which represent the proportions of early apoptotic and late apoptotic/early necrotic cells present, respectively, were significantly lower in the immunized group. Our findings suggest that the apoptotic splenocytes in immunized chickens significantly decreased in number, which occurred concomitantly with a significant rise in systemic immune response and bacterial clearance. This suggests that inhibition of apoptosis may be a marker of protection efficacy in immunized chickens.
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Affiliation(s)
- Nitin M Kamble
- College of Veterinary Medicine, Chonbuk National University, Jeonbuk 570-752, South Korea
| | - Rahul M Nandre
- College of Veterinary Medicine, Chonbuk National University, Jeonbuk 570-752, South Korea
| | - John Hwa Lee
- College of Veterinary Medicine, Chonbuk National University, Jeonbuk 570-752, South Korea.
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7
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γδ T cells exhibit multifunctional and protective memory in intestinal tissues. Immunity 2013; 39:184-95. [PMID: 23890071 DOI: 10.1016/j.immuni.2013.06.015] [Citation(s) in RCA: 166] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 06/27/2013] [Indexed: 01/13/2023]
Abstract
The study of T cell memory and the target of vaccine design have focused on memory subsumed by T cells bearing the αβ T cell receptor. Alternatively, γδ T cells are thought to provide rapid immunity, particularly at mucosal borders. Here, we have shown that a distinct subset of mucosal γδ T cells mounts an immune response to oral Listeria monocytogenes (Lm) infection and leads to the development of multifunctional memory T cells capable of simultaneously producing interferon-γ and interleukin-17A in the murine intestinal mucosa. Challenge infection with oral Lm, but not oral Salmonella or intravenous Lm, induced rapid expansion of memory γδ T cells, suggesting contextual specificity to the priming pathogen. Importantly, memory γδ T cells were able to provide enhanced protection against infection. These findings illustrate that γδ T cells play a role with hallmarks of adaptive immunity in the intestinal mucosa.
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Lee SJ, Dunmire S, McSorley SJ. MHC class-I-restricted CD8 T cells play a protective role during primary Salmonella infection. Immunol Lett 2012; 148:138-43. [PMID: 23089550 DOI: 10.1016/j.imlet.2012.10.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 09/25/2012] [Accepted: 10/10/2012] [Indexed: 11/25/2022]
Abstract
Protective immunity against Salmonella infection is known to require CD4 Th1 cells and B cells, but the role of MHC class-I-restricted CD8 T cells is less clear. Previous studies have suggested that CD8 T cells participate in secondary, but not primary, bacterial clearance. However, these studies have used experimental models that are difficult to interpret and do not clearly isolate the role of MHC class-I-restricted CD8 T cells from other cell populations. Here, we examined the role of class-I-restricted T cells in protection against Salmonella infection using mice lacking all classical MHC class-Ia molecules, perforin, or granzyme B. Immunized K(b)D(b)-, perforin-, granzyme B-, or perforin/granzyme B-deficient mice were able to resolve secondary infection with virulent Salmonella, demonstrating that class-I-restricted CTLs are not required for acquired immunity. However, during primary infection with attenuated bacteria, bacterial clearance was delayed in each of these mouse strains when compared to wild-type mice. Taken together, these data demonstrate that CD8 T cells are not required for acquired immunity to Salmonella, but can play a protective role in resolving primary infection with attenuated bacteria.
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Affiliation(s)
- Seung-Joo Lee
- Center for Comparative Medicine, Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA.
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Penha Filho RAC, Moura BS, de Almeida AM, Montassier HJ, Barrow PA, Berchieri Junior A. Humoral and cellular immune response generated by different vaccine programs before and after Salmonella Enteritidis challenge in chickens. Vaccine 2012; 30:7637-43. [PMID: 23085366 DOI: 10.1016/j.vaccine.2012.10.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 09/01/2012] [Accepted: 10/04/2012] [Indexed: 12/24/2022]
Abstract
The poultry industry has a high demand for Salmonella vaccines in order to generate safer Salmonella-free food for consumers around the world. Vaccination against S. Enteritidis (SE) is vastly undertaken in many countries, although the criteria for the use of live vaccine (LV) or killed vaccine (KV) should also depend on the immune mechanisms triggered by each. In this study, a commercial bacterin (KV) and an attenuated SG mutant (LV) were used in four different vaccine programs (LV; LV+LV; KV; LV+KV). At 1 day before (dbi) and 1, 6 and 9 days after SE challenge (dpi), humoral (IgM, IgG and secretory IgA) and cellular (CD8(+) T cells) immune responses were evaluated along with the production of IL-10, IL-12 and IFN-γ. Although after challenge, all birds from each group had an influx of CD8(+) T cells, birds which received KV had lower levels of these cells in organs and significantly higher levels of immunoglobulins. The expression of the cytokines was up-regulated in all groups post-vaccination, although, after challenge, cytokine expression decreased in the vaccinated groups, and increased in the unvaccinated group A. IL-10 levels were significantly higher at 1 day post-infection in the group that received KV, which may be involved in the weak cellular immune response observed within this group. In caecal tonsils, IFN-γ expression at 1 dbi was higher in birds which received two vaccine doses, and after challenge, the population of CD8(+) T cells constantly increased in birds that were only vaccinated with the LV. This study demonstrated that the development of a mature immune response by CD8(+) T cells, provided by the use of the LV, had better efficacy in comparison to the high antibody levels in the serum stimulated by the KV. However, high secretory IgA levels in the intestinal lumen associated with influx CD8(+) T cells may be indicative of protection as noticed in group E (LV+KV).
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Abstract
Over the last decade, significant advances have been made in the methodology for studying immune responses in vivo. It is now possible to follow almost every aspect of pathogen-specific immunity using in vivo models that incorporate physiological infectious doses and natural routes of infection. This new ability to study immunity in a relevant physiological context will greatly expand our understanding of the dynamic interplay between host and pathogen. Visualizing the resolution of primary infection and the development of long-term immunological memory should also aid the development of new vaccines and therapeutics for infectious diseases. In this review, we will describe the application of in vivo visualization technology to Salmonella infection, describe our current understanding of Salmonella-specific immunity, and discuss some unanswered questions that remain in this model.
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Affiliation(s)
- James J. Moon
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN, 55455
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN, 55455
| | - Stephen J. McSorley
- Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, 55455
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN, 55455
- Center for Infectious Diseases & Microbiology Translational Research, University of Minnesota Medical School, Minneapolis, MN, 55455
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