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Ma X, Lu X, Zhang W, Yang L, Wang D, Xu J, Jia Y, Wang X, Xie H, Li S, Zhang M, He Y, Jin P, Sheng J. Gut microbiota in the early stage of Crohn’s disease has unique characteristics. Gut Pathog 2022; 14:46. [DOI: 10.1186/s13099-022-00521-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 12/06/2022] [Indexed: 12/15/2022] Open
Abstract
Abstract
Background
Emerging evidence suggests that gut microbiota plays a predominant role in Crohn’s disease (CD). However, the microbiome alterations in the early stage of CD patients still remain unclear. The present study aimed to identify dysbacteriosis in patients with early CD and explore specific gut bacteria related to the progression of CD.
Methods
This study was nested within a longitudinal prospective Chinese CD cohort, and it included 18 early CD patients, 22 advanced CD patients and 30 healthy controls. The microbiota communities were investigated using high-throughput Illumina HiSeq sequencing targeting the V3–V4 region of 16S ribosomal DNA (rDNA) gene. The relationship between the gut microbiota and clinical characteristics of CD was analyzed.
Results
Differential microbiota compositions were observed in CD samples (including early and advanced CD samples) and healthy controls samples. Notably, Lachnospiracea_incertae_sedis and Parabacteroides were enriched in the early CD patients, Escherichia/Shigella, Enterococcus and Proteus were enriched in the advanced CD patients, and Roseburia, Gemmiger, Coprococcus, Ruminococcus 2, Butyricicoccus, Dorea, Fusicatenibacter, Anaerostipes, Clostridium IV were enriched in the healthy controls [LDA score (log10) > 2]. Furthermore, Kruskal–Wallis Rank sum test results showed that Blautia, Clostridium IV, Coprococcus, Dorea, Fusicatenibacter continued to significantly decrease in early and advanced CD patients, and Escherichia/Shigella and Proteus continued to significantly increase compared with healthy controls (P < 0.05). The PICRUSt analysis identified 16 remarkably different metabolic pathways [LDA score (log10) > 2]. Some genera were significantly correlated with various clinical parameters, such as fecal calprotectin, erythrocyte sedimentation rate, C-reactive protein, gland reduce, goblet cells decreased, clinical symptoms (P < 0.05).
Conclusions
Dysbacteriosis occurs in the early stage of CD and is associated with the progression of CD. This data provides a foundation that furthers the understanding of the role of gut microbiota in CD’s pathogenesis.
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Yang J, Guo Y, Lee R, Henning SM, Wang J, Pan Y, Qing T, Hsu M, Nguyen A, Prabha S, Ojha R, Small GW, Heber D, Li Z. Pomegranate Metabolites Impact Tryptophan Metabolism in Humans and Mice. Curr Dev Nutr 2020; 4:nzaa165. [PMID: 33274309 PMCID: PMC7695807 DOI: 10.1093/cdn/nzaa165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/12/2020] [Accepted: 10/22/2020] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND We showed that pomegranate juice (PomJ) can help to maintain memory in adults aged >50 y. The mechanism for this effect is unknown, but might involve Trp and its metabolites, which are important in brain function. OBJECTIVES We aimed to test the hypothesis that PomJ and its metabolites ellagic acid (EA) and urolithin A (UA) affect Trp metabolism. METHODS Stool and plasma from a cohort [11 PomJ, 9 placebo drink (PL)] of subjects enrolled in our double-blind, placebo-controlled trial (NCT02093130) were collected at baseline and after 1 y of PomJ or PL consumption. In a mouse study, cecum and serum were collected from DBA/2J mice receiving 8 wk of dietary 0.1% EA or UA supplementation. Trp metabolites and intestinal microbiota were analyzed by LC-MS and 16S rRNA gene sequencing, respectively. RESULTS In the human study, the change in the plasma Trp metabolite indole propionate (IPA) over 1 y was significantly different between PomJ and PL groups (P = 0.03). In serum of experimental mice, we observed a 230% increase of IPA by EA but not UA, a 54% increase of indole sulfate by UA but not EA, and 43% and 34% decreases of kynurenine (KYN) by EA and UA, respectively. In cecum, there was a 32% decrease of Trp by UA but not EA, and an 86% decrease of KYN by EA but not UA (P < 0.05). The abundance of 2 genera, Shigella and Catenibacterium, was reduced by PomJ in humans as well as by UA in mice, and their abundance was negatively associated with blood IPA in humans and mice (P < 0.05). CONCLUSIONS These results suggest a novel mechanism involving the regulation of host and microbial Trp metabolism that might contribute to the health benefits of ellagitannins and EA-enriched food, such as PomJ.
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Affiliation(s)
- Jieping Yang
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Yuanqiang Guo
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin, China
| | - Rupo Lee
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Susanne M Henning
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Jing Wang
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Yajing Pan
- Key Laboratory of Health Cultivation of the Ministry of Education, Beijing University of Chinese Medicine , Beijing, China
| | - Tianyu Qing
- Key Laboratory of Health Cultivation of the Ministry of Education, Beijing University of Chinese Medicine , Beijing, China
| | - Mark Hsu
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Alex Nguyen
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Siddarth Prabha
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Rashi Ojha
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Gary W Small
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - David Heber
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Zhaoping Li
- Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Medicine, VA Greater Los Angeles Health Care System , Los Angeles, CA, USA
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Toapanta FR, Bernal PJ, Kotloff KL, Levine MM, Sztein MB. T cell mediated immunity induced by the live-attenuated Shigella flexneri 2a vaccine candidate CVD 1208S in humans. J Transl Med 2018. [PMID: 29534721 PMCID: PMC5851169 DOI: 10.1186/s12967-018-1439-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Background Shigellosis persists as a public health problem worldwide causing ~ 165,000 deaths every year, of which ~ 55,000 are in children less than 5 years of age. No vaccine against shigellosis is currently licensed. The live-attenuated Shigella flexneri 2a vaccine candidate CVD 1208S (S. flexneri 2a; ΔguaBA, Δset, Δsen) demonstrated to be safe and immunogenic in phase 1 and 2 clinical trials. Earlier reports focused on humoral immunity. However, Shigella is an intracellular pathogen and therefore, T cell mediated immunity (T-CMI) is also expected to play an important role. T-CMI responses after CVD 1208S immunization are the focus of the current study. Methods Consenting volunteers were immunized orally (3 doses, 108 CFU/dose, 28 days apart) with CVD 1208S. T-CMI to IpaB was assessed using autologous EBV-transformed B-Lymphocytic cell lines as stimulator cells. T-CMI was assessed by the production of 4 cytokines (IFN-γ, IL-2, IL-17A and TNF-α) and/or expression of the degranulation marker CD107a in 14 volunteers (11 vaccine and 3 placebo recipients). Results Following the first immunization, T-CMI was detected in CD8 and CD4 T cells obtained from CVD 1208S recipients. Among CD8 T cells, the T effector memory (TEM) and central memory (TCM) subsets were the main cytokine/CD107a producers/expressors. Multifunctional (MF) cells were also detected in CD8 TEM cells. Cells with 2 and 3 functions were the most abundant. Interestingly, TNF-α appeared to be dominant in CD8 TEM MF cells. In CD4 T cells, TEM responses predominated. Following subsequent immunizations, no booster effect was detected. However, production of cytokines/expression of CD107a was detected in individuals who had previously not responded. After three doses, production of at least one cytokine/CD107a was detected in 8 vaccinees (73%) in CD8 TEM cells and in 10 vaccinees (90%) in CD4 TEM cells. Conclusions CVD 1208S induces diverse T-CMI responses, which likely complement the humoral responses in protection from disease. Trial registration This study was approved by the Institutional Review Board and registered on ClinicalTrials.gov (identifier NCT01531530) Electronic supplementary material The online version of this article (10.1186/s12967-018-1439-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Franklin R Toapanta
- Department of Medicine, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
| | - Paula J Bernal
- Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Karen L Kotloff
- Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Myron M Levine
- Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Marcelo B Sztein
- Department of Medicine, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. .,Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
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Davis CL, Wahid R, Toapanta FR, Simon JK, Sztein MB. A clinically parameterized mathematical model of Shigella immunity to inform vaccine design. PLoS One 2018; 13:e0189571. [PMID: 29304144 PMCID: PMC5755796 DOI: 10.1371/journal.pone.0189571] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 11/16/2017] [Indexed: 11/28/2022] Open
Abstract
We refine and clinically parameterize a mathematical model of the humoral immune response against Shigella, a diarrheal bacteria that infects 80-165 million people and kills an estimated 600,000 people worldwide each year. Using Latin hypercube sampling and Monte Carlo simulations for parameter estimation, we fit our model to human immune data from two Shigella EcSf2a-2 vaccine trials and a rechallenge study in which antibody and B-cell responses against Shigella′s lipopolysaccharide (LPS) and O-membrane proteins (OMP) were recorded. The clinically grounded model is used to mathematically investigate which key immune mechanisms and bacterial targets confer immunity against Shigella and to predict which humoral immune components should be elicited to create a protective vaccine against Shigella. The model offers insight into why the EcSf2a-2 vaccine had low efficacy and demonstrates that at a group level a humoral immune response induced by EcSf2a-2 vaccine or wild-type challenge against Shigella′s LPS or OMP does not appear sufficient for protection. That is, the model predicts an uncontrolled infection of gut epithelial cells that is present across all best-fit model parameterizations when fit to EcSf2a-2 vaccine or wild-type challenge data. Using sensitivity analysis, we explore which model parameter values must be altered to prevent the destructive epithelial invasion by Shigella bacteria and identify four key parameter groups as potential vaccine targets or immune correlates: 1) the rate that Shigella migrates into the lamina propria or epithelium, 2) the rate that memory B cells (BM) differentiate into antibody-secreting cells (ASC), 3) the rate at which antibodies are produced by activated ASC, and 4) the Shigella-specific BM carrying capacity. This paper underscores the need for a multifaceted approach in ongoing efforts to design an effective Shigella vaccine.
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Affiliation(s)
- Courtney L. Davis
- Natural Science Division, Pepperdine University, Malibu, CA, United States of America
- * E-mail:
| | - Rezwanul Wahid
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Franklin R. Toapanta
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Jakub K. Simon
- Merck & Co. Inc. Kenilworth, NJ, United States of America
| | - Marcelo B. Sztein
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
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Qian T, Zhang R, Zhu L, Shi P, Yang J, Yang CY, Chen DM, Shi JY, Zhou XG, Qiu YP, Yang Y, He L, He SR, Cao YT, Wei QF, Kumar M, Chen C. Necrotizing enterocolitis in low birth weight infants in China: Mortality risk factors expressed by birth weight categories. Pediatr Neonatol 2017; 58:509-515. [PMID: 28528756 DOI: 10.1016/j.pedneo.2016.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 09/21/2016] [Accepted: 10/14/2016] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND We retrospectively investigated incidence, morbidity, and mortality of neonatal necrotizing enterocolitis in China, with special emphasis on determining the predictors of necrotizing enterocolitis associated mortality. METHODS We identified neonates as having necrotizing enterocolitis if they met the accepted diagnostic criterion. Data pertaining to antenatal period, labor and birth, and the postnatal course of illness were collected. Multivariate analysis and logistic regression were used to analyze the risk factors. RESULTS There were 1167 cases of necrotizing enterocolitis identified from the 95 participating NICUs in mainland China in 2011, with the incidence of 2.50% and 4.53% in LBW (birth weight <2500 g) and VLBW (birth weight <1500 g) infants, respectively. Stage 1, 2 and 3 diseases were noted in 51.1%, 30.3% and 18.6% of cases respectively. The mortality from stage 2 and 3 necrotizing enterocolitis in this cohort was 41.7%. In VLBW infants, the important risk factors for mortality were small for gestation age (OR: 5.02, 95% CI 1.73-14.6; P = 0.003) and stage 3 NEC (OR: 8.09, 95% CI 2.80-23.3, P < 0.001). In moderate LBW infants (birth weight 1500-2499 g), the risk factors identified for mortality were sepsis during hospitalization (OR: 2.59, 95% CI 1.57-4.28, P < 0.001) and stage 3 NEC (OR: 5.37, 95% CI 3.24-8.90; P < 0.001). CONCLUSIONS Necrotizing enterocolitis remains an important cause of morbidity and mortality in prematurely born neonates in Chinese neonatal units. Awareness of the associated risk factors and appropriate interventions may improve the outcome of necrotizing enterocolitis in different birth weight subgroup.
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Affiliation(s)
- Tian Qian
- Children's Hospital of Fudan University and the Laboratory of Neonatal Diseases of Ministry of Health, Shanghai, China
| | - Rong Zhang
- Children's Hospital of Fudan University and the Laboratory of Neonatal Diseases of Ministry of Health, Shanghai, China
| | - Li Zhu
- Children's Hospital of Fudan University and the Laboratory of Neonatal Diseases of Ministry of Health, Shanghai, China
| | - Peng Shi
- Children's Hospital of Fudan University and the Laboratory of Neonatal Diseases of Ministry of Health, Shanghai, China
| | - Jie Yang
- Guangdong Provincial Maternity Hospital, Guangzhou, China
| | | | | | - Jing-Yun Shi
- Gansu Provincial Maternity Hospital, Lanzhou, China
| | - Xiao-Guang Zhou
- Nanjing Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Yin-Ping Qiu
- General Hospital of Ningxia Medical University, Yinchuan, China
| | - Yong Yang
- Dongguan Maternity Hospital, Dongguan, China
| | - Ling He
- Jiangxi Provincial Children's Hospital, Nanchang, China
| | - Shao-Ru He
- Guangdong Provincial People's Hospital, Guangzhou, China
| | - Yun-Tao Cao
- Affiliated Hospital of Zunyi Medical College, Zunyi, China
| | - Qiu-Fen Wei
- Maternal and Child Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | | | - Chao Chen
- Children's Hospital of Fudan University and the Laboratory of Neonatal Diseases of Ministry of Health, Shanghai, China.
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Poole NM, Green SI, Rajan A, Vela LE, Zeng XL, Estes MK, Maresso AW. Role for FimH in Extraintestinal Pathogenic Escherichia coli Invasion and Translocation through the Intestinal Epithelium. Infect Immun 2017; 85:e00581-17. [PMID: 28808163 DOI: 10.1128/IAI.00581-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 08/11/2017] [Indexed: 12/27/2022] Open
Abstract
The translocation of bacteria across the intestinal epithelium of immunocompromised patients can lead to bacteremia and life-threatening sepsis. Extraintestinal pathogenic Escherichia coli (ExPEC), so named because this pathotype infects tissues distal to the intestinal tract, is a frequent cause of such infections, is often multidrug resistant, and chronically colonizes a sizable portion of the healthy population. Although several virulence factors and their roles in pathogenesis are well described for ExPEC strains that cause urinary tract infections and meningitis, they have not been linked to translocation through intestinal barriers, a fundamentally distant yet important clinical phenomenon. Using untransformed ex situ human intestinal enteroids and transformed Caco-2 cells, we report that ExPEC strain CP9 binds to and invades the intestinal epithelium. ExPEC harboring a deletion of the gene encoding the mannose-binding type 1 pilus tip protein FimH demonstrated reduced binding and invasion compared to strains lacking known E. coli virulence factors. Furthermore, in a murine model of chemotherapy-induced translocation, ExPEC lacking fimH colonized at levels comparable to that of the wild type but demonstrated a statistically significant reduction in translocation to the kidneys, spleen, and lungs. Collectively, this study indicates that FimH is important for ExPEC translocation, suggesting that the type 1 pilus is a therapeutic target for the prevention of this process. Our study also highlights the use of human intestinal enteroids in the study of enteric diseases.
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Arena ET, Tinevez JY, Nigro G, Sansonetti PJ, Marteyn BS. The infectious hypoxia: occurrence and causes during Shigella infection. Microbes Infect 2016; 19:157-165. [PMID: 27884799 DOI: 10.1016/j.micinf.2016.10.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 10/27/2016] [Accepted: 10/31/2016] [Indexed: 12/19/2022]
Abstract
Hypoxia is defined as a tissue oxygenation status below physiological needs. During Shigella infection, an infectious hypoxia is induced within foci of infection. In this review, we discuss how Shigella physiology and virulence are modulated and how the main recruited immune cells, the neutrophils, adapt to this environment.
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Affiliation(s)
- Ellen T Arena
- Institut Pasteur, Unité de Pathogénie Microbienne Moléculaire, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; INSERM Unité 1202, 28 rue du Dr Roux, 75724 Paris Cedex 15, France
| | - Jean-Yves Tinevez
- Institut Pasteur, Citech, Imagopole, 28 rue du Dr Roux, 75724 Paris Cedex 15, France
| | - Giulia Nigro
- Institut Pasteur, Unité de Pathogénie Microbienne Moléculaire, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; INSERM Unité 1202, 28 rue du Dr Roux, 75724 Paris Cedex 15, France
| | - Philippe J Sansonetti
- Institut Pasteur, Unité de Pathogénie Microbienne Moléculaire, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; INSERM Unité 1202, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; Collège de France, 11 Place Marcellin Berthelot, F-75231, Paris Cedex 05, France
| | - Benoit S Marteyn
- Institut Pasteur, Unité de Pathogénie Microbienne Moléculaire, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; INSERM Unité 1202, 28 rue du Dr Roux, 75724 Paris Cedex 15, France; Gustave Roussy Cancer Campus, Laboratoire de Thérapie Cellulaire, 114 Rue Edouard Vaillant, 94800 Villejuif, France.
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Nag D, Koley H, Sinha R, Mukherjee P, Sarkar C, Withey JH, Gachhui R. Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae. Scand J Immunol 2016; 83:92-101. [PMID: 26478541 DOI: 10.1111/sji.12394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/06/2015] [Indexed: 02/03/2023]
Abstract
An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future.
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Affiliation(s)
- D Nag
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - H Koley
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - R Sinha
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - P Mukherjee
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - C Sarkar
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - J H Withey
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - R Gachhui
- Department of Life Science and Technology, Jadavpur University, Kolkata, India
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9
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Nag D, Sinha R, Mitra S, Barman S, Takeda Y, Shinoda S, Chakrabarti MK, Koley H. Heat killed multi-serotype Shigella immunogens induced humoral immunity and protection against heterologous challenge in rabbit model. Immunobiology 2015. [PMID: 26210044 DOI: 10.1016/j.imbio.2015.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently we have shown the homologous protective efficacy of heat killed multi-serotype Shigella (HKMS) immunogens in a guinea pig colitis model. In our present study, we have advanced our research by immunizing rabbits with a reduced number of oral doses and evaluating the host's adaptive immune responses. The duration of immunogenicity and subsequently protective efficacy was determined against wild type heterologous Shigella strains in a rabbit luminal model. After three successive oral immunizations with HKMS immunogens, serum and lymphocyte supernatant antibody titer against the heterologous shigellae were reciprocally increased and remained at an elevated level up to 180 days. Serogroup and serotype specific O-antigen of lipopolysaccharide and immunogenic proteins of heterologous challenge strains were detected by immunoblot assay. Up-regulation of IL-12p35, IFN-γ and IL-10 mRNA expression was detected in immunized rabbit peripheral blood mononuclear cells (PBMC) after stimulation with HKMS in vitro. HKMS-specific plasma cell response was confirmed by production of a relatively higher level of HKMS-specific IgG in immunized PBMC supernatant compared to control group. Furthermore, the immunized groups of rabbits exhibited complete protection against wild type heterologous shigellae challenge. Thus HKMS immunogens induced humoral and Th1-mediated adaptive immunity and provided complete protection in a rabbit model. These immunogens could be a broad spectrum non-living vaccine candidate for human use in the near future.
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Affiliation(s)
- Dhrubajyoti Nag
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Ritam Sinha
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Soma Mitra
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Soumik Barman
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Yoshifumi Takeda
- Collaborative Research Centre of Okayama University for Infectious Diseases, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sumio Shinoda
- Collaborative Research Centre of Okayama University for Infectious Diseases, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - M K Chakrabarti
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Hemanta Koley
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India.
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Toapanta FR, Simon JK, Barry EM, Pasetti MF, Levine MM, Kotloff KL, Sztein MB. Gut-Homing Conventional Plasmablasts and CD27(-) Plasmablasts Elicited after a Short Time of Exposure to an Oral Live-Attenuated Shigella Vaccine Candidate in Humans. Front Immunol 2014; 5:374. [PMID: 25191323 PMCID: PMC4138503 DOI: 10.3389/fimmu.2014.00374] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/22/2014] [Indexed: 12/05/2022] Open
Abstract
Currently, there is no licensed Shigella vaccine; however, various promising live-attenuated vaccine candidates have emerged, including CVD1208S (ΔguaBA, Δset, Δsen S. flexneri 2a), which was shown to be safe and immunogenic in Phase 1 clinical trials. Here, we report the immune responses elicited in an outpatient Phase 2 clinical trial in which subjects were vaccinated with CVD 1208S. Oral immunization with CVD 1208S elicited high anti-S. flexneri 2a LPS and IpaB antibody responses as well as an acute plasmablast (PB) infiltration in peripheral blood 7 days after immunization. PB sorted based on their expression of homing molecules confirmed that cells expressing integrin α4β7 alone or in combination with CD62L were responsible for antibody production (as measured by ELISpot). Furthermore, using high-color flow-cytometry, on day 7 after immunization, we observed the appearance of conventional PB (CPB, CD19dim CD20− CD27+high CD38+high CD3−), as well as a PB population that did not express CD27 (CD27− PB; pre-plasmablasts). The pattern of individual or simultaneous expression of homing markers (integrin α4β7, CD62L, CXCR3, and CXCR4) suggested that CPB cells homed preferentially to the inflamed gut mucosa. In contrast, ~50% CD27− PB cells appear to home to yet to be identified peripheral lymphoid organs or were in a transition state preceding integrin α4β7 upregulation. In sum, these observations demonstrate that strong immune responses, including distinct PB subsets with the potential to home to the gut and other secondary lymphoid organs, can be elicited after a short time of exposure to a shigella oral vaccine.
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Affiliation(s)
- Franklin R Toapanta
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Medicine, University of Maryland School of Medicine , Baltimore, MD , USA
| | | | - Eileen M Barry
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Microbiology and Immunology, University of Maryland School of Medicine , Baltimore, MD , USA
| | - Marcela F Pasetti
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Pediatrics, University of Maryland School of Medicine , Baltimore, MD , USA
| | - Myron M Levine
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Medicine, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Pediatrics, University of Maryland School of Medicine , Baltimore, MD , USA
| | - Karen L Kotloff
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Medicine, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Pediatrics, University of Maryland School of Medicine , Baltimore, MD , USA
| | - Marcelo B Sztein
- Center for Vaccine Development, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Microbiology and Immunology, University of Maryland School of Medicine , Baltimore, MD , USA ; Department of Pediatrics, University of Maryland School of Medicine , Baltimore, MD , USA
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11
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Schröder-Braunstein J, Gras J, Brors B, Schwarz S, Szikszai T, Lasitschka F, Wabnitz G, Heidtmann A, Lee YS, Schiessling S, Leowardi C, Al-Saeedi M, Ulrich A, Engelke A, Winter J, Samstag Y, Giese T, Meuer S. Initiation of an inflammatory response in resident intestinal lamina propria cells -use of a human organ culture model. PLoS One 2014; 9:e97780. [PMID: 24841635 PMCID: PMC4026413 DOI: 10.1371/journal.pone.0097780] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 04/22/2014] [Indexed: 01/30/2023] Open
Abstract
Resident human lamina propria immune cells serve as powerful effectors in host defense. Molecular events associated with the initiation of an intestinal inflammatory response in these cells are largely unknown. Here, we aimed to characterize phenotypic and functional changes induced in these cells at the onset of intestinal inflammation using a human intestinal organ culture model. In this model, healthy human colonic mucosa was depleted of epithelial cells by EDTA treatment. Following loss of the epithelial layer, expression of the inflammatory mediators IL1B, IL6, IL8, IL23A, TNFA, CXCL2, and the surface receptors CD14, TLR2, CD86, CD54 was rapidly induced in resident lamina propria cells in situ as determined by qRT-PCR and immunohistology. Gene microarray analysis of lamina propria cells obtained by laser-capture microdissection provided an overview of global changes in gene expression occurring during the initiation of an intestinal inflammatory response in these cells. Bioinformatic analysis gave insight into signalling pathways mediating this inflammatory response. Furthermore, comparison with published microarray datasets of inflamed mucosa in vivo (ulcerative colitis) revealed a significant overlap of differentially regulated genes underlining the in vivo relevance of the organ culture model. Furthermore, genes never been previously associated with intestinal inflammation were identified using this model. The organ culture model characterized may be useful to study molecular mechanisms underlying the initiation of an intestinal inflammatory response in normal mucosa as well as potential alterations of this response in inflammatory bowel disease.
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Affiliation(s)
| | - Judith Gras
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Benedikt Brors
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sonja Schwarz
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Timea Szikszai
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
- Department of Anesthesiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Felix Lasitschka
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Guido Wabnitz
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Antje Heidtmann
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Young-Seon Lee
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, Hannover, Germany
| | - Serin Schiessling
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
- Department of Surgery, University Hospital Heidelberg, Heidelberg, Germany
| | - Christine Leowardi
- Department of Surgery, University Hospital Heidelberg, Heidelberg, Germany
| | - Mohammed Al-Saeedi
- Department of Surgery, University Hospital Heidelberg, Heidelberg, Germany
| | - Alexis Ulrich
- Department of Surgery, University Hospital Heidelberg, Heidelberg, Germany
| | | | - Johannes Winter
- Department of Surgery, St. Vincentius Hospital, Speyer, Germany
| | - Yvonne Samstag
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Thomas Giese
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Stefan Meuer
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
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12
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Abstract
Several live-attenuated Shigella vaccines, with well-defined mutations in specific genes, have shown great promise in eliciting significant immune responses when given orally to volunteers. These responses have been measured by evaluating antibody-secreting cells, serum antibody levels and fecal immunoglobulin A to bacterial lipopolysaccharide and to individual bacterial invasion plasmid antigens. In this review, data collected from volunteer trials with live Shigella vaccines from three different research groups are described. The attenuating features of the bacterial strains, as well as the immune response following the use of different dosing regimens, are also described. The responses obtained with each vaccine strain are compared with data obtained from challenge trials using wild-type Shigella strains. Although the exact correlates of protection have not been found, some consensus may be derived as to what may constitute a protective immune response. Future directions in the field of live Shigella vaccines are also discussed.
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Affiliation(s)
- Malabi M Venkatesan
- Division of Bacterial and Rickettsial Diseases, Walter Reed Army Institute of Research, 503 Robert Forney Drive, Room 3s12, Silver Spring, MD 20910, USA.
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13
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Fisher ML, Sun W, Curtiss R. The route less taken: pulmonary models of enteric Gram-negative infection. Pathog Dis 2013; 70:99-109. [PMID: 24259516 DOI: 10.1111/2049-632x.12109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/16/2013] [Indexed: 11/29/2022] Open
Abstract
Many pathogens are capable of causing a fulminant infection in pulmonary tissues of mammals. Animal models have provided an extensive understanding of the genetic and molecular mechanisms of bacterial pathogenesis as well as host immune response in the lungs. Many clinically relevant Gram-negative bacteria are host-restricted. Thus, the powerful, informative tools of mouse models are not available for study with these organisms. However, over the past 30 years, enterprising work has demonstrated the utility of pulmonary infection with enteric pathogens. Such infection models have increased our understanding host-pathogen interactions in these organisms. Here, we provide a review and comparison of lung models of infection with enteric, Gram-negative bacteria relative to naturally occurring lung pathogens.
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Affiliation(s)
- Michael L Fisher
- Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, AZ, USA
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14
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Abstract
The burden of dysentery due to shigellosis among children in the developing world is still a major concern. A safe and efficacious vaccine against this disease is a priority, since no licensed vaccine is available. This review provides an update of vaccine achievements focusing on subunit vaccine strategies and the forthcoming strategies surrounding this approach. In particular, this review explores several aspects of the pathogenesis of shigellosis and the elicited immune response as being the basis of vaccine requirements. The use of appropriate Shigella antigens, together with the right adjuvants, may offer safety, efficacy and more convenient delivery methods for massive worldwide vaccination campaigns.
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15
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Mitra S, Chakrabarti MK, Koley H. Multi-serotype outer membrane vesicles of Shigellae confer passive protection to the neonatal mice against shigellosis. Vaccine 2013; 31:3163-73. [DOI: 10.1016/j.vaccine.2013.05.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 03/14/2013] [Accepted: 05/01/2013] [Indexed: 12/27/2022]
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16
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Affiliation(s)
- Allen G P Ross
- Griffith Health Institute, Griffith University, Gold Coast, QLD, Australia.
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17
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Davis CL, Wahid R, Toapanta FR, Simon JK, Sztein MB, Levy D. Applying mathematical tools to accelerate vaccine development: modeling Shigella immune dynamics. PLoS One 2013; 8:e59465. [PMID: 23589755 PMCID: PMC3614931 DOI: 10.1371/journal.pone.0059465] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 02/11/2013] [Indexed: 12/02/2022] Open
Abstract
We establish a mathematical framework for studying immune interactions with Shigella, a bacteria that kills over one million people worldwide every year. The long-term goal of this novel approach is to inform Shigella vaccine design by elucidating which immune components and bacterial targets are crucial for establishing Shigella immunity. Our delay differential equation model focuses on antibody and B cell responses directed against antigens like lipopolysaccharide in Shigella’s outer membrane. We find that antibody-based vaccines targeting only surface antigens cannot elicit sufficient immunity for protection. Additional boosting prior to infection would require a four-orders-of-magnitude increase in antibodies to sufficiently prevent epithelial invasion. However, boosting anti-LPS B memory can confer protection, which suggests these cells may correlate with immunity. We see that IgA antibodies are slightly more effective per molecule than IgG, but more total IgA is required due to spatial functionality. An extension of the model reveals that targeting both LPS and epithelial entry proteins is a promising avenue to advance vaccine development. This paper underscores the importance of multifaceted immune targeting in creating an effective Shigella vaccine. It introduces mathematical models to the Shigella vaccine development effort and lays a foundation for joint theoretical/experimental/clinical approaches to Shigella vaccine design.
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Affiliation(s)
- Courtney L Davis
- Natural Science Division, Pepperdine University, Malibu, California, United States of America.
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18
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Burnaevskiy N, Fox TG, Plymire DA, Ertelt JM, Weigele BA, Selyunin AS, Way SS, Patrie SM, Alto NM. Proteolytic elimination of N-myristoyl modifications by the Shigella virulence factor IpaJ. Nature 2013; 496:106-9. [PMID: 23535599 DOI: 10.1038/nature12004] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 02/12/2013] [Indexed: 12/13/2022]
Abstract
Protein N-myristoylation is a 14-carbon fatty-acid modification that is conserved across eukaryotic species and occurs on nearly 1% of the cellular proteome. The ability of the myristoyl group to facilitate dynamic protein-protein and protein-membrane interactions (known as the myristoyl switch) makes it an essential feature of many signal transduction systems. Thus pathogenic strategies that facilitate protein demyristoylation would markedly alter the signalling landscape of infected host cells. Here we describe an irreversible mechanism of protein demyristoylation catalysed by invasion plasmid antigen J (IpaJ), a previously uncharacterized Shigella flexneri type III effector protein with cysteine protease activity. A yeast genetic screen for IpaJ substrates identified ADP-ribosylation factor (ARF)1p and ARF2p, small molecular mass GTPases that regulate cargo transport through the Golgi apparatus. Mass spectrometry showed that IpaJ cleaved the peptide bond between N-myristoylated glycine-2 and asparagine-3 of human ARF1, thereby providing a new mechanism for host secretory inhibition by a bacterial pathogen. We further demonstrate that IpaJ cleaves an array of N-myristoylated proteins involved in cellular growth, signal transduction, autophagasome maturation and organelle function. Taken together, these findings show a previously unrecognized pathogenic mechanism for the site-specific elimination of N-myristoyl protein modification.
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Affiliation(s)
- Nikolay Burnaevskiy
- Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8816, USA
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19
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Abstract
Much is known about the molecular effectors of pathogenicity of gram-negative enteric pathogens, among which Shigella can be considered a model. This is due to its capacity to recapitulate the multiple steps required for a pathogenic microbe to survive close to its mucosal target, colonize and then invade its epithelial surface, cause its inflammatory destruction and simultaneously regulate the extent of the elicited innate response to likely survive the encounter and achieve successful subsequent transmission. These various steps of the infectious process represent an array of successive environmental conditions to which the bacteria need to successfully adapt. These conditions represent the selective pressure that triggered the "arms race" in which Shigella acquired the genetic and molecular effectors of its pathogenic armory, including the regulatory hierarchies that regulate the expression and function of these effectors. They also represent cues through which Shigella achieves the temporo-spatial expression and regulation of its virulence effectors. The role of such environmental cues has recently become obvious in the case of the major virulence effector of Shigella, the type three secretion system (T3SS) and its dedicated secreted virulence effectors. It needs to be better defined for other major virulence components such as the LPS and peptidoglycan which are used as examples here, in addition to the T3SS as models of regulation as it relates to the assembly and functional regulation of complex macromolecular systems of the bacterial surface. This review also stresses the need to better define what the true and relevant environmental conditions can be at the various steps of the progression of infection. The "identity" of the pathogen differs depending whether it is cultivated under in vitro or in vivo conditions. Moreover, this "identity" may quickly change during its progression into the infected tissue. Novel concepts and relevant tools are needed to address this challenge in microbial pathogenesis.
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Affiliation(s)
- Benoit Marteyn
- Unité de Pathogénie Microbienne Moléculaire; Institut Pasteur; Paris, France,Unité INSERM 786; Institut Pasteur; Paris, France
| | - Anastasia Gazi
- Unité de Pathogénie Microbienne Moléculaire; Institut Pasteur; Paris, France,Unité INSERM 786; Institut Pasteur; Paris, France
| | - Philippe Sansonetti
- Unité de Pathogénie Microbienne Moléculaire; Institut Pasteur; Paris, France,Unité INSERM 786; Institut Pasteur; Paris, France,Chaire de Microbiologie et Maladies Infectieuses; Collège de France; Paris, France,Correspondence to: Philippe Sansonetti,
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20
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Abstract
Shigellosis is a major form of bacillary dysentery caused by Shigella spp. To date, there is no suitable animal model to evaluate the protective efficacy of vaccine candidates against this pathogen. Here, we describe a successful experimental shigellosis in the guinea-pig model, which has shown the characteristic features of human shigellosis. This model yielded reproducible results without any preparatory treatment besides cecal ligation. In this study, guinea-pigs were discretely infected with virulent Shigella dysenteriae type 1 and Shigella flexneri type 2a into the cecocolic junction after ligation of the distal cecum. All the experimental animals lost ∼10% of their body weight and developed typical dysentery within 24-h postinfection. In the histological analysis, distal colon showed edema, hemorrhage, exudation and inflammatory infiltrations in the lamina propria. Orally immunized animals with heat-killed S. dysenteriae type 1 and S. flexneri type 2a strains showed high levels of serum immunoglobulin G (IgG) and mucosal IgA antibodies and conferred significant homologous protective immunity against subsequent challenges with the live strains. The direct administration of shigellae into the cecocolic junction induces acute inflammation, making this animal model useful for assessing shigellosis and evaluating the protective immunity of Shigella vaccine candidates.
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Affiliation(s)
- Soumik Barman
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
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21
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Abstract
PURPOSE OF REVIEW The incidence of gastrointestinal infections continues to increase and infectious colitis contributes to significant morbidity and mortality worldwide. The purpose of this review is to highlight the recent advances in knowledge of pathogens causing infectious colitis. We describe the various pathogens and specifically focus on enterohemorrhagic Escherichia coli (EHEC) O157:H7, Salmonella, Shigella, Campylobacter, and Entamoeba histolytica infections, and their impact on long-term effects, including postinfectious irritable bowel syndrome and inflammatory bowel disease. RECENT FINDINGS Salmonella, Campylobacter, and EHEC outbreaks continue to occur with disturbing regularity. Peanut butter and peppers were recently responsible for outbreaks of nontyphoid Salmonella. Recent research has identified Salmonella genes required for colonization of various hosts and transposon-mediated differential hybridization was recently used to identify genes required during infection in different animal models. A number of other strains of EHEC in addition to O157:H7 are emerging as serious threats to food safety in the USA. Campylobacter jejuni isolates are of interest because of absence of genes encoding for classical enterotoxins, and lack of plasmids encoding genes promoting bacterial invasion. Recent research has identified that the organism is able to invade and replicate in infected epithelia via Toll-like receptor (TLR)-2 and TLR-4. Also patients with infectious colitis, in particular Salmonella and Campylobacter, are at increased risk of postinfectious irritable bowel syndrome and inflammatory bowel disease on long-term follow-up. The paradigm of Entamoeba histolytica infection is changing with recent reports of detection of E. dispar deoxyribonucleic acid sequences, previously considered nonpathogenic. SUMMARY There has been an explosion in the understanding of the epidemiology, pathobiology, and mechanisms underlying infectious colitis. Additional studies to address prevention strategies and strict screening modalities for these infections are necessary.
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22
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Morinaga Y, Yanagihara K, Nakamura S, Hasegawa H, Seki M, Izumikawa K, Kakeya H, Yamamoto Y, Yamada Y, Kohno S, Kamihira S. Legionella pneumophila induces cathepsin B-dependent necrotic cell death with releasing high mobility group box1 in macrophages. Respir Res 2010; 11:158. [PMID: 21092200 PMCID: PMC3003236 DOI: 10.1186/1465-9921-11-158] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2010] [Accepted: 11/22/2010] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Legionella pneumophila (LPN) can cause a lethal infectious disease with a marked inflammatory response in humans. However, the mechanism of this severe inflammation remains poorly understood. Since necrosis is known to induce inflammation, we investigated whether LPN induces necrosis in macrophages. We also analyzed the involvement of lysosomal cathepsin B in LPN-induced cell death. METHODS The human monocytic cell line THP-1 was infected with LPN, NUL1 strain. MG132-treated cells were used as apoptotic control cells. After infection, the type of cell death was analyzed by using microscopy, LDH release and flow cytometry. As a proinflammatory mediator, high-mobility group box 1 (HMGB-1), was measured. Cathepsin B activity was also measured and the inhibitory effects of cathepsin B on LPN-induced cell death were analyzed. RESULTS THP-1 cells after treatment with high dose of LPN showed necrotic features with releasing HMGB-1. This necrosis and the HMGB-1 release were inhibited by a specific lysosomal cathepsin B inhibitor and were characterized by a rapid and high activation of cathepsin B that was not observed in apoptotic control cells. The necrosis was also accompanied by cathepsin B-dependent poly(ADP-ribose) polymerase (PARP) cleavage. CONCLUSIONS We demonstrate here that L. pneumophila rapidly induces cathepsin B-dependent necrosis in a dose-dependent manner and releases a proinflammatory mediator, HMGB-1, from macrophages. This report describes a novel aspect of the pathogenesis of Legionnaires' disease and provides a possible therapeutic target for the regulation of inflammation.
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Affiliation(s)
- Yoshitomo Morinaga
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Shigeki Nakamura
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Hiroo Hasegawa
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Masafumi Seki
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Koichi Izumikawa
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Hiroshi Kakeya
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Yoshihiro Yamamoto
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Yasuaki Yamada
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Shigeru Kohno
- Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
- Global COE Program, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
| | - Shimeru Kamihira
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 851-2128, Japan
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23
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Rawal M, Hoff E, Aas-Pedersen L, Haugum K, Lindstedt BA. Rapid multiple-locus variable-number tandem-repeats analysis of Shigella spp. using multicolour capillary electrophoresis. J Microbiol Methods 2010; 83:279-85. [PMID: 20951171 DOI: 10.1016/j.mimet.2010.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 10/01/2010] [Accepted: 10/06/2010] [Indexed: 01/21/2023]
Abstract
The multiple-locus variable-number tandem-repeats analysis (MLVA) method for genotyping has proven to be a fast and reliable typing tool in several bacterial species. MLVA is in our laboratory the routine typing method for Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli (two assays), Listeria monocytogenes and Yersinia enterocolitica. The gram-negative invasive enteropathogenic bacterium Shigella is the most common cause of bacillary dysentery (shigellosis) worldwide, and is a global human health problem. It was of great interest to develop a rapid and robust MLVA-assay for this important pathogen. Though not common in Norway, we do receive isolates mostly associated with foreign travel and thus an outbreak may be possible. The resulting MLVA-assay is based on seven polymorphous VNTRs found by search in the published genomes of all Shigella species. The assay is fast (one multiplexed PCR reaction), robust and show high divergence among the Shigellae. A total of 235 Shigella spp. were typed with 194 distinct MLVA-genotypes. An outbreak cluster of Shigella sonnei was additionally identified during manuscript preparation.
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Affiliation(s)
- Monica Rawal
- Division of Infectious Diseases control, Norwegian Institute of Public Health, Lovisenberggata 8, P.O. Box 4404 Nydalen, N-0403 Oslo, Norway
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24
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Abstract
Bacterial translocation from the gastrointestinal tract is an important pathway initiating late-onset sepsis and necrotizing enterocolitis in very low-birth-weight infants. The emerging intestinal microbiota, nascent intestinal epithelia, naive immunity, and suboptimal nutrition (lack of breast milk) have roles in facilitating bacterial translocation. Feeding lactoferrin, probiotics, or prebiotics has presented exciting possibilities to prevent bacterial translocation in preterm infants, and clinical trials will identify the most safe and efficacious prevention and treatment strategies.
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26
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Abstract
Infectious diarrhea is an important public health problem worldwide. Research has provided new insights into the mechanisms of diarrhea caused by various pathogens that are classified as noninflammatory, inflammatory or invasive. These three groups of organisms cause two diarrheal syndromes--noninflammatory diarrhea and inflammatory diarrhea. The noninflammatory diarrheas are caused by enterotoxin-producing organisms such as Vibrio cholerae and enterotoxigenic Escherichia coli, or by viruses that adhere to the mucosa and disrupt the absorptive and/or secretory processes of the enterocyte without causing acute inflammation or mucosal destruction. Inflammatory diarrhea is caused by two groups of organisms--cytotoxin-producing, noninvasive bacteria (e.g. enteroaggregative Escherichia coli, enterohemorrhagic Escherichia coli and Clostridium difficile), or by invasive organisms (e.g. Salmonella spp., Shigella spp., Campylobacter spp., Entamoeba histolytica). The cytotoxin-producing organisms adhere to the mucosa, activate cytokines and stimulate the intestinal mucosa to release inflammatory mediators. Invasive organisms, which can also produce cytotoxins, invade the intestinal mucosa to induce an acute inflammatory reaction, involving the activation of cytokines and inflammatory mediators. Regardless of the underlying mechanism they use, these various types of pathogen have all successfully evolved to evade and modulate the host defense systems. The mechanisms by which the different pathogens invade the host and cause infectious diarrhea are the topic of this Review.
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Affiliation(s)
- Udayakumar Navaneethan
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0595, USA
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27
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Nagy G, Emo˝dy L, Pál T. Strategies for the development of vaccines conferring broad-spectrum protection. Int J Med Microbiol 2008; 298:379-95. [DOI: 10.1016/j.ijmm.2008.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 11/07/2007] [Accepted: 01/14/2008] [Indexed: 11/21/2022] Open
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28
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Wong D, Bazopoulou D, Pujol N, Tavernarakis N, Ewbank JJ. Genome-wide investigation reveals pathogen-specific and shared signatures in the response of Caenorhabditis elegans to infection. Genome Biol 2008; 8:R194. [PMID: 17875205 PMCID: PMC2375032 DOI: 10.1186/gb-2007-8-9-r194] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 09/14/2007] [Accepted: 09/17/2007] [Indexed: 01/12/2023] Open
Abstract
Microarray analysis of the transcriptional response of C. elegans to four bacterial pathogens revealed that different infections trigger responses, some of which are common to all four pathogens, such as necrotic cell death, which has been associated with infection in humans. Background There are striking similarities between the innate immune systems of invertebrates and vertebrates. Caenorhabditis elegans is increasingly used as a model for the study of innate immunity. Evidence is accumulating that C. elegans mounts distinct responses to different pathogens, but the true extent of this specificity is unclear. Here, we employ direct comparative genomic analyses to explore the nature of the host immune response. Results Using whole-genome microarrays representing 20,334 genes, we analyzed the transcriptional response of C. elegans to four bacterial pathogens. Different bacteria provoke pathogen-specific signatures within the host, involving differential regulation of 3.5-5% of all genes. These include genes that encode potential pathogen-recognition and antimicrobial proteins. Additionally, variance analysis revealed a robust signature shared by the pathogens, involving 22 genes associated with proteolysis, cell death and stress responses. The expression of these genes, including those that mediate necrosis, is similarly altered following infection with three bacterial pathogens. We show that necrosis aggravates pathogenesis and accelerates the death of the host. Conclusion Our results suggest that in C. elegans, different infections trigger both specific responses and responses shared by several pathogens, involving immune defense genes. The response shared by pathogens involves necrotic cell death, which has been associated with infection in humans. Our results are the first indication that necrosis is important for disease susceptibility in C. elegans. This opens the way for detailed study of the means by which certain bacteria exploit conserved elements of host cell-death machinery to increase their effective virulence.
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Affiliation(s)
- Daniel Wong
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, Case 906, 13288 Marseille Cedex 9, France
- Institut National de la Santé et de la Recherche Médicale, U631, 13288 Marseille, France
- Centre National de la Recherche Scientifique, UMR6102, 13288 Marseille, France
| | - Daphne Bazopoulou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion 71110, Crete, Greece
| | - Nathalie Pujol
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, Case 906, 13288 Marseille Cedex 9, France
- Institut National de la Santé et de la Recherche Médicale, U631, 13288 Marseille, France
- Centre National de la Recherche Scientifique, UMR6102, 13288 Marseille, France
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion 71110, Crete, Greece
| | - Jonathan J Ewbank
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, Case 906, 13288 Marseille Cedex 9, France
- Institut National de la Santé et de la Recherche Médicale, U631, 13288 Marseille, France
- Centre National de la Recherche Scientifique, UMR6102, 13288 Marseille, France
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29
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Abstract
Shigella, a Gram-negative invasive enteropathogenic bacterium, causes the rupture, invasion and inflammatory destruction of the human colonic epithelium. This complex and aggressive process accounts for the symptoms of bacillary dysentery. The so-called invasive phenotype of Shigella is linked to expression of a type III secretory system (TTSS) injecting effector proteins into the epithelial cell membrane and cytoplasm, thereby inducing local but massive changes in the cell cytoskeleton that lead to bacterial internalization into non-phagocytic intestinal epithelial cells. The invasive phenotype also accounts for the potent pro-inflammatory capacity of the microorganism. Recent evidence indicates that a large part of the mucosal inflammation is initiated by intracellular sensing of bacterial peptidoglycan by cytosolic leucine-rich receptors of the NOD family, particularly NOD1, in epithelial cells. This causes activation of the nuclear factor kappa B and c-JunNH(2)-terminal-kinase pathways, with interleukin-8 appearing as a major chemokine mediating the inflammatory burst that is dominated by massive infiltration of the mucosa by polymorphonuclear leukocytes. Not unexpectedly, this inflammatory response, which is likely to be very harmful for the invading microbe, is regulated by the bacterium itself. A group of proteins encoded by Shigella, which are injected into target cells by the TTSS, has been recently recognized as a family of potent regulators of the innate immune response. These enzymes target key cellular functions that are essential in triggering the inflammatory response, and more generally defense responses of the intestinal mucosa. This review focuses on the mechanisms employed by Shigella to manipulate the host innate response in order to escape early bacterial killing, thus ensuring establishment of its infectious process. The escape strategies, the possible direct effect of Shigella on B and T lymphocytes, their impact on the development of adaptive immunity, and how they may help explain the limited protection induced by natural infection are discussed.
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Affiliation(s)
- Armelle Phalipon
- Unité de Pathogénie Microbienne Moléculaire, INSERM U786, Institut Pasteur 25, Rue du Dr Roux, Paris, France.
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30
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Suzuki T, Yoshikawa Y, Ashida H, Iwai H, Toyotome T, Matsui H, Sasakawa C. High Vaccine Efficacy against Shigellosis of Recombinant NoninvasiveShigellaMutant That ExpressesYersiniaInvasin. J Immunol 2006; 177:4709-17. [PMID: 16982910 DOI: 10.4049/jimmunol.177.7.4709] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Live attenuated Shigella vaccines elicit protective immune responses, but involve a potential risk of inducing a strong inflammatory reaction. The bacterial invasiveness that is crucial for Ag delivery causes inflammatory destruction of infected epithelial cells and proinflammatory cell death of infected macrophages. In this study, the noninvasive Shigella mutant DeltaipaB was equipped with Yersinia invasin protein, which has been shown to mediate bacterial invasion and targeting to M cells located in follicle-associated epithelium. Invasin-expressing DeltaipaB (DeltaipaB/inv) was internalized into epithelial cells and retained in the intraphagosomal space. DeltaipaB/inv did not induce necrotic cell death of infected macrophages nor cause symptomatic damage after intranasal vaccination of mice. DeltaipaB/inv was safer and more effective than the conventional live vaccine, DeltavirG. Infection by DeltaipaB/inv caused polymorphonuclear neutrophil infiltration in the lung, but did not induce production of large amounts of proinflammatory cytokines. We concluded that the low experimental morbidity and high vaccine efficacy of DeltaipaB/inv are primarily based on high protective immune responses, which may be enhanced by the polymorphonuclear neutrophil infiltration unaccompanied by tissue injury.
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Affiliation(s)
- Toshihiko Suzuki
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
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31
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Payne SM, Wyckoff EE, Murphy ER, Oglesby AG, Boulette ML, Davies NML. Iron and pathogenesis of Shigella: iron acquisition in the intracellular environment. Biometals 2006; 19:173-80. [PMID: 16718602 DOI: 10.1007/s10534-005-4577-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Accepted: 10/24/2005] [Indexed: 10/24/2022]
Abstract
Shigella species are able to grow in a variety of environments, including intracellularly in host epithelial cells. Shigella have a number of different iron transport systems that contribute to their ability to grow in these diverse environments. Siderophore iron uptake systems, heme transporters, and ferric and ferrous iron transport systems are present in these bacteria, and the genes encoding some of these systems appear to have spread among the Shigella species by horizontal transmission. Iron is not only essential for growth of Shigella but also plays an important role in regulation of metabolic processes and virulence determinants in Shigella. This regulation is mediated by the repressor protein Fur and the small RNA RyhB.
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Affiliation(s)
- Shelley M Payne
- Section of Molecular Genetics and Microbiology, The University of Texas at Austin, Austin, TX, 78712, USA.
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32
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Johnson S, Roversi P, Espina M, Deane JE, Birket S, Picking WD, Blocker A, Picking WL, Lea SM. Expression, limited proteolysis and preliminary crystallographic analysis of IpaD, a component of the Shigella flexneri type III secretion system. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:865-8. [PMID: 16946465 PMCID: PMC1894744 DOI: 10.1107/s1744309106027047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Accepted: 07/12/2006] [Indexed: 01/22/2023]
Abstract
IpaD, the putative needle-tip protein of the Shigella flexneri type III secretion system, has been overexpressed and purified. Crystals were grown of the native protein in space group P2(1)2(1)2(1), with unit-cell parameters a = 55.9, b = 100.7, c = 112.0 A, and data were collected to 2.9 A resolution. Analysis of the native Patterson map revealed a peak at 50% of the origin on the Harker section v = 0.5, suggesting twofold non-crystallographic symmetry parallel to the b crystallographic axis. As attempts to derivatize or grow selenomethionine-labelled protein crystals failed, in-drop proteolysis was used to produce new crystal forms. A trace amount of subtilisin Carlsberg was added to IpaD before sparse-matrix screening, resulting in the production of several new crystal forms. This approach produced SeMet-labelled crystals and diffraction data were collected to 3.2 A resolution. The SeMet crystals belong to space group C2, with unit-cell parameters a = 139.4, b = 45.0, c = 99.5 A, beta = 107.9 degrees . An anomalous difference Patterson map revealed peaks on the Harker section v = 0, while the self-rotation function indicates the presence of a twofold noncrystallographic symmetry axis, which is consistent with two molecules per asymmetric unit.
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Affiliation(s)
- Steven Johnson
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, England
- Sir William Dunn School of Pathology, University of Oxford, England
| | - Pietro Roversi
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, England
| | | | - Janet E. Deane
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, England
| | - Susan Birket
- Department of Molecular Biosciences, University of Kansas, USA
| | | | - Ariel Blocker
- Sir William Dunn School of Pathology, University of Oxford, England
| | | | - Susan M. Lea
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, England
- Sir William Dunn School of Pathology, University of Oxford, England
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33
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Abstract
Pro-inflammatory macrophage apoptosis is pivotal in the aetiology of bacillary dysentery, an acute inflammatory diarrhoea caused by Shigella spp. S. flexneri triggers its uptake by macrophages, escapes the phagosome and kills the host cell by a cytotoxic pathway, which activates and requires caspase-1 [interleukin (IL)-1beta-converting enzyme] and releases mature IL-1beta. The bacterial type III-secreted translocator/effector protein IpaB triggers cell death and directly binds to caspase-1. Here, we demonstrate that in S. flexneri-infected macrophages, activated caspase-1 is present in the cytoplasm, the nucleus and on vesicular membranes. IpaB partitions with membrane and cytoplasmic fractions and colocalizes with activated caspase-1 on the surface of bacteria, in the macrophage cytoplasm and on vesicular membranes. Macrophages treated with the cholesterol-sequestering compound methyl-beta-cyclodextrin (MCD) were depleted from cholesterol within minutes and were impaired for phagocytosis of S. flexneri. Consequently, cytotoxicity as determined by lactate dehydrogenase release was blocked. Interestingly, if MCD was added 15-30 min post infection, cytotoxicity, activation of caspase-1, and apoptosis were inhibited, while phagocytosis of the bacteria, escape from the phagosome and type III secretion of IpaB was not affected. Inhibition of Shigella cytotoxicity by MCD coincided with a reduced association of IpaB to host cell membranes. Contrarily, the activation of caspase-1 and cytotoxicity triggered by the K+/H+ antiport ionophore nigericin or by ATP was not affected or even increased by MCD. These results indicate that cholesterol is specifically required for caspase-1 activation and apoptosis triggered by Shigella after the escape from phagosomes, and suggest that membrane association of IpaB contributes to the activation of caspase-1.
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Affiliation(s)
- Gunnar N Schroeder
- Institute of Microbiology, ETH Zürich, Wolfgang-Pauli Strasse 10, 8093 Zürich, Switzerland
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34
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Berlutti F, Schippa S, Morea C, Sarli S, Perfetto B, Donnarumma G, Valenti P. Lactoferrin downregulates pro-inflammatory cytokines upexpressed in intestinal epithelial cells infected with invasive or noninvasive Escherichia coli strainsThis paper is one of a selection of papers published in this Special Issue, entitled 7th International Conference on Lactoferrin: Structure, Function, and Applications, and has undergone the Journal’s usual peer review process. Biochem Cell Biol 2006; 84:351-7. [PMID: 16936806 DOI: 10.1139/o06-039] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Intestinal epithelial cells are able to differentially interact with commensal or pathogenic microorganisms, triggering a physiological or destructive inflammation, respectively. To mimic commensal–enteroinvasive bacteria–host cell interaction, we infected Caco-2 cells with noninvasive Escherichia coli HB101 and with recombinant invasive E. coli HB101(pRI203). Using DNA microarray mRNA profiling and ELISA assays, we studied the expression of several cytokine and cytokine-related genes in infected Caco-2 cells in the absence or presence of bovine lactoferrin (bLf). Infection of Caco-2 cells with the noninvasive strain induced a slight increase in the expression of interleukin 8 (IL-8), whereas infection with invasive E. coli HB101(pRI203) induced a significant increase in the expression of IL-8 as well as other pro-inflammatory cytokines. The addition of bLf, in native- or holo-form, did not influence expression of cytokine genes by uninfected Caco-2 cells, but it decreased expression of IL-8 by cells infected with E.coli HB101. Moreover, except for IL-8, bLfs dramatically downregulated pro-inflammatory cytokines upexpressed by Caco-2 cells infected with the invasive strain. Although IL-8 was decreased by bLfs, it remained upregulated, suggesting that it could be a signal of persistence of intracellular bacteria. The bLf ability to reduce expression of some pro-inflammatory cytokines, which appears independent of its iron saturation, might represent an important natural mechanism in regulating epithelial cell responses to pathogenic bacteria and in limiting cell damage and the spread of infections.
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Affiliation(s)
- Francesca Berlutti
- Department of Public Health Sciences, University of Rome La Sapienza, Rome, Italy
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35
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Phalipon A, Costachel C, Grandjean C, Thuizat A, Guerreiro C, Tanguy M, Nato F, Vulliez-Le Normand B, Bélot F, Wright K, Marcel-Peyre V, Sansonetti PJ, Mulard LA. Characterization of functional oligosaccharide mimics of the Shigella flexneri serotype 2a O-antigen: implications for the development of a chemically defined glycoconjugate vaccine. J Immunol 2006; 176:1686-94. [PMID: 16424198 DOI: 10.4049/jimmunol.176.3.1686] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Protection against reinfection with noncapsulated Gram-negative bacteria, such as Shigella, an enteroinvasive bacterium responsible for bacillary dysentery, is mainly achieved by Abs specific for the O-Ag, the polysaccharide part of the LPS, the major bacterial surface Ag. The use of chemically defined glycoconjugates encompassing oligosaccharides mimicking the protective determinants carried by the O-Ag, thus expected to induce an efficient anti-LPS Ab response, has been considered an alternative to detoxified LPS-protein conjugate vaccines. The aim of this study was to identify such functional oligosaccharide mimics of the S. flexneri serotype 2a O-Ag. Using protective murine mAbs specific for S. flexneri serotype 2a and synthetic oligosaccharides designed to analyze the contribution of each sugar residue of the branched pentasaccharide repeating unit of the O-Ag, we demonstrated that the O-Ag exhibited an immunodominant serotype-specific determinant. We also showed that elongating the oligosaccharide sequence improved Ab recognition. From these antigenicity data, selected synthetic oligosaccharides were assessed for their potential to mimic the O-Ag by analyzing their immunogenicity in mice when coupled to tetanus toxoid via single point attachment. Our results demonstrated that induction of an efficient serotype 2a-specific anti-O-Ag Ab response was dependent on the length of the oligosaccharide sequence. A pentadecasaccharide representing three biological repeating units was identified as a potential candidate for further development of a chemically defined glycoconjugate vaccine against S. flexneri 2a infection.
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Affiliation(s)
- Armelle Phalipon
- Unité de Pathogénie Microbienne Moléculaire, Institut National de la Santé et de la Recherche Médicale Unité 389.
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36
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Taylor DN, McKenzie R, Durbin A, Carpenter C, Atzinger CB, Haake R, Bourgeois AL. Rifaximin, a nonabsorbed oral antibiotic, prevents shigellosis after experimental challenge. Clin Infect Dis 2006; 42:1283-8. [PMID: 16586388 DOI: 10.1086/503039] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Accepted: 12/23/2005] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND This double-blind, placebo-controlled study was conducted to assess the efficacy of the nonabsorbed oral antibiotic rifaximin to prevent shigellosis in volunteers challenged with Shigella flexneri. METHODS Volunteers were randomized to receive either prophylactic rifaximin (200 mg 3 times daily for 3 days; n = 15) or placebo (n = 10) on days 0, 1, and 2. On day 1, volunteers were challenged with approximately 1500 colony-forming units of S. flexneri 2a strain 2457T given orally in sodium bicarbonate buffer. RESULTS The incidence of diarrhea was 0 with rifaximin, compared with 60% with placebo (P = .001). The median time to onset of diarrhea was 78.5 h with placebo (P < .001). The incidence of dysentery was 0 for rifaximin and 10% for placebo (P = .4). The incidence of colonization with Shigella was 0 with rifaximin, compared with 50% with placebo (P < .005). A significant serum or mucosal immune response after challenge by at least 1 indicator (immunoglobulin A titer, immunoglobulin G titer, and immunoglobulin A antibody-secreting cell count) was 0 with rifaximin and 80% with placebo (P < .001). CONCLUSIONS Rifaximin was effective and well tolerated, compared with placebo, in preventing shigellosis in this double-blind study of volunteers challenged with S. flexneri 2a.
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Affiliation(s)
- David N Taylor
- Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
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37
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Orr N, Katz DE, Atsmon J, Radu P, Yavzori M, Halperin T, Sela T, Kayouf R, Klein Z, Ambar R, Cohen D, Wolf MK, Venkatesan MM, Hale TL. Community-based safety, immunogenicity, and transmissibility study of the Shigella sonnei WRSS1 vaccine in Israeli volunteers. Infect Immun 2006; 73:8027-32. [PMID: 16299296 PMCID: PMC1307051 DOI: 10.1128/iai.73.12.8027-8032.2005] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We describe the first community-based evaluation of Shigella sonnei strain WRSS1, a live, oral candidate vaccine attenuated by a 212-bp deletion in the virG (or icsA) plasmid virulence gene. Three single-dose regimens of WRSS1 (5 x 10(3) CFU, 2 x 10(4) CFU, and 4 x 10(5) CFU) were tested with cohorts of 15 adult volunteers. The vaccine was generally well tolerated at the 10(3)- and 10(4)-CFU doses. There were no fevers and there was one report of moderate diarrhea in 30 vaccinees; five additional vaccinees reported mild diarrhea. At the 10(5)-CFU dose, there were two reports of low-grade fevers and four reports of moderate diarrhea. The geometric means for immunoglobulin A (IgA) antibody-secreting cells (ASC) against lipopolysaccharide (LPS) were 30, 75, and 193 ASC per 10(6) peripheral blood mononuclear cells (PBMC) for the 10(3)-, 10(4)-, and 10(5)-CFU doses, respectively. The IgG means were 40, 46, and 135 ASC per 10(6) PBMC, respectively. The 10(4)-CFU dose of WRSS1 gave the best balance of safety and immunogenicity, since all vaccinees had a significant IgA ASC response and 73% had a response of more than 50 ASC. The anti-LPS seroconversion rate (threefold) for IgA was 60% and the IgG rate was 27% for the 10(4)-CFU cohort. Each vaccinee and a cohabitating household contact delivered daily perianal stool swabs for bacteriological culture. WRSS1 colonized vaccinees for a median of 5 days, and one individual excreted WRSS1 intermittently for 23 days. None of the 45 household contacts were colonized with WRSS1 after a cumulative 192 days of cohabitation with colonized vaccinees, suggesting that adventitious vaccine spread was not common in the community setting.
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Affiliation(s)
- Nadav Orr
- Center for Vaccine Development and Evaluation, Medical Corps, Israel Defense Force, Tel-Aviv, Israel
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38
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Abstract
Organismal homeostasis depends on an intricate balance between cell death and renewal. Early pathologists recognized that this balance could be disrupted by the extensive damage observed in internal organs during the course of certain diseases. This form of tissue damage was termed "necrosis", derived from the Greek "nekros" for corpse. As it became clear that the essential building block of tissue was the cell, necrosis came to be used to describe pathologic cell death. Until recently, necrotic cell death was believed to result from injuries that caused an irreversible bioenergetic compromise. The cell dying by necrosis has been viewed as a victim of extrinsic events beyond its control. However, recent evidence suggests that a cell can initiate its own demise by necrosis in a manner that initiates both inflammatory and/or reparative responses in the host. By initiating these adaptive responses, programmed cell necrosis may serve to maintain tissue and organismal integrity.
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Affiliation(s)
- Wei-Xing Zong
- Department of Molecular Genetics and Microbiology, State University of New York at Stony Brook, New York 11794, USA
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39
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Abstract
Bacteria of Shigella spp. (S. boydii, S. dysenteriae, S. flexneri and S. sonnei) and enteroinvasive Escherichia coli (EIEC) are responsible for shigellosis in humans, a disease characterized by the destruction of the colonic mucosa that is induced upon bacterial invasion. Shigella spp. and EIEC strains contain a virulence plasmid of approximately 220 kb that encodes determinants for entry into epithelial cells and dissemination from cell to cell. This review presents the current model on mechanisms of invasion of the colonic epithelium by these bacteria and focuses on their pathogenicity factors, particularly the virulence plasmid-encoded type III secretion system.
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Affiliation(s)
- Claude Parsot
- Unité de Pathogénie Microbienne Moléculaire, INSERM U389, Institut Pasteur, 25 rue du Dr Roux, 75724 Paris Cedex 15, France.
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40
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Wolf R, Grimaldi E, Donnarumma G, Greco R, Auricchio L, De Filippis A, Tufano MA. Quinine sulfate inhibits invasion of Salmonella typhimurium and Shigella flexneri: a preliminary study. J Travel Med 2005; 12:343-6. [PMID: 16343387 DOI: 10.2310/7060.2005.12608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The incidence of typhoid fever and shigellosis parallels that of malaria, so many individuals who are on antimalarial drugs can be found in areas where these diseases are widespread. We investigated the effect of quinine sulfate on the growth and invasion of Salmonella typhimurium and Shigella flexneri M90T to determine whether people on antimalarials can have secondary gain from some protection against typhoid fever and shigellosis. METHODS The effect of 50 and 100 microM quinine sulfate on the invasive ability of Salmonella typhimurium and Shigella flexneri M90T into human colon adenocarcinoma-2 (Caco-2) cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria by counting the colony-forming units. RESULTS The invasive ability of Salmonella typhimurium and Shigella flexneri M90T was significantly inhibited by 50 and 100 microM quinine sulfate in a dose-dependent manner (for Salmonella typhimurium) when the drug was added to Caco-2 cell monolayers during the infection period. CONCLUSIONS Since so many people who are on antimalarial drugs visit and inhabit areas that are endemic to typhoid fever and Shigella infection, a study on the influence of these drugs on the disease is long overdue. Our data indicate that quinine sulfate interferes with the invasion and internalization of Salmonella typhimurium and Shigella flexneri M90T into host cells. Further studies on additional strains/serotypes with other newer antimalarials at various concentrations are needed to verify this effect of quinine sulfate and to draw conclusions on its significance in vivo.
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Affiliation(s)
- Ronni Wolf
- Dermitology Unit, Kaplan Medical Center, Rechovot, Isreal
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41
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Le-Barillec K, Magalhaes JG, Corcuff E, Thuizat A, Sansonetti PJ, Phalipon A, Di Santo JP. Roles for T and NK cells in the innate immune response to Shigella flexneri. J Immunol 2005; 175:1735-40. [PMID: 16034114 DOI: 10.4049/jimmunol.175.3.1735] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Shigella flexneri, an enteroinvasive Gram-negative bacterium, is responsible for the worldwide endemic form of bacillary dysentery. The host response to primary infection is characterized by the induction of an acute inflammation, which is accompanied by polymorphonuclear cell (PMN) infiltration, resulting in massive destruction of the colonic mucosa. However, PMN play a major role in the recovery from primary infection, by restricting the bacterial infection at the intestinal mucosa. In this study, we assessed the roles for T and NK cells in the control of primary S. flexneri infection, using an alymphoid mouse strain (Rag null gamma(c) null) devoid of B, T, and NK cells. Using the mouse pulmonary model of Shigella infection, we showed that alymphoid Rag null gamma(c) null mice were highly susceptible to S. flexneri infection in comparison with wild-type (wt) mice. Whereas PMN recruitment upon infection was similar, macrophage recruitment and production of proinflammatory cytokines were significantly decreased in Rag null gamma(c) null mice compared with wt mice. Upon selective engraftment of Rag null gamma(c) null mice with polyclonal alphabeta T cells, but not with alphabeta T cells from IFN-gamma null , S. flexneri infection could be subsequently controlled. Rag null mice devoid of B and T cells but harboring NK cells could control infection. Local IFN-gamma production by T and NK cells recruited to the lung was demonstrated in S. flexneri-infected wt mice. These data demonstrate that both alphabeta T cells and NK cells contribute to the early control of S. flexneri infection through amplification of an inflammatory response. This cellular lymphocyte redundancy assures IFN-gamma production, which is central to innate immunity against Shigella infection.
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MESH Headings
- Animals
- DNA-Binding Proteins/deficiency
- DNA-Binding Proteins/genetics
- Dysentery, Bacillary/genetics
- Dysentery, Bacillary/immunology
- Dysentery, Bacillary/prevention & control
- Genetic Predisposition to Disease
- Homeodomain Proteins/genetics
- Immunity, Innate/genetics
- Inflammation Mediators/physiology
- Interferon-gamma/biosynthesis
- Interleukin Receptor Common gamma Subunit
- Intestinal Mucosa/immunology
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/microbiology
- Intestinal Mucosa/pathology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Lung/immunology
- Lung/metabolism
- Lung/microbiology
- Lung/pathology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Receptors, Antigen, T-Cell, alpha-beta/administration & dosage
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Interleukin-7/deficiency
- Receptors, Interleukin-7/genetics
- Shigella flexneri/immunology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/transplantation
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Affiliation(s)
- Karine Le-Barillec
- Unité des Cytokines et Développement Lymphoide, Institut National de la Santé et de la Recherche Médicale, Unité 668, Paris cedex, France
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42
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Clément MJ, Fortuné A, Phalipon A, Marcel-Peyre V, Simenel C, Imberty A, Delepierre M, Mulard LA. Toward a better understanding of the basis of the molecular mimicry of polysaccharide antigens by peptides: the example of Shigella flexneri 5a. J Biol Chem 2005; 281:2317-32. [PMID: 16251186 DOI: 10.1074/jbc.m510172200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein conjugates of oligosaccharides or peptides that mimic complex bacterial polysaccharide antigens represent alternatives to the classical polysaccharide-based conjugate vaccines developed so far. Hence, a better understanding of the molecular basis ensuring appropriate mimicry is required in order to design efficient carbohydrate mimic-based vaccines. This study focuses on the following two unrelated sets of mimics of the Shigella flexneri 5a O-specific polysaccharide (O-SP): (i) a synthetic branched pentasaccharide known to mimic the average solution conformation of S. flexneri 5a O-SP, and (ii) three nonapeptides selected upon screening of phage-displayed peptide libraries with two protective murine monoclonal antibodies (mAbs) of the A isotype specific for S. flexneri 5a O-SP. By inducing anti-O-SP antibodies upon immunization in mice when appropriately presented to the immune system, the pentasaccharide and peptides p100c and p115, but not peptide p22, were qualified as mimotopes of the native antigen. NMR studies based on transferred NOE (trNOE) experiments revealed that both kinds of mimotopes had an average conformation when bound to the mAbs that was close to that of their free form. Most interestingly, saturation transfer difference (STD) experiments showed that the characteristic turn conformations adopted by the major conformers of p100c and p115, as well as of p22, are clearly involved in mAb binding. These latter experiments also showed that the branched glucose residue of the pentasaccharide was a key part of the determinant recognized by the protective mAbs. Finally, by using NMR-derived pentasaccharide and peptide conformations coupled to STD information, models of antigen-antibody interaction were obtained. Most interestingly, only one model was found compatible with experimental data when large O-SP fragments were docked into one of the mIgA-binding sites. This newly made available system provides a new contribution to the understanding of the molecular mimicry of complex polysaccharides by peptides and short oligosaccharides.
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Affiliation(s)
- Marie-Jeanne Clément
- Unité de RMN des Biomolécules, URA CNRS 2185, Institut Pasteur, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France
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Hummel S, Apte RN, Qimron U, Vitacolonna M, Porgador A, Zöller M. Tumor Vaccination by Salmonella typhimurium After Transformation with a Eukaryotic Expression Vector in Mice. J Immunother 2005; 28:467-79. [PMID: 16113603 DOI: 10.1097/01.cji.0000170359.92090.8b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Transformed attenuated Salmonella typhimurium (ST) have been suggested as an efficient means of tumor vaccination. However, ST themselves might be immunosuppressive, and the question has arisen as to whether this impedes vaccination efficacy even if ST are transformed with a eukaryotic expression vector such that "tumor antigen" will be transcribed by the host. The question was evaluated using a mutant SL7207, where the yej operon, which interferes with MHC I-mediated presentation, had been inactivated (SL7207DeltayejE). Mice were vaccinated with SL7207 or SL7207DeltayejE transformed with a eukaryotic expression vector carrying the lacZ or the gp100 gene and later received lacZ-transfected RENCA or YC8 or gp100-expressing B16F1 tumor cells. In vaccinated mice, tumor growth started with a delay and some animals remained tumor-free; however, the tumor growth rate remained unaltered. No significant difference was seen between SL7207DeltayejE versus SL7207 vaccinated mice. The latter finding contrasted with ex vivo analyses where vaccination with SL7207DeltayejE, compared with SL7207, induced a significantly stronger response, including nonadaptive defense mechanisms. The failure to detect a superior vaccination efficacy of SL7207DeltayejE in vivo could be attributed to a stronger effect of the yej operon on MHC-mediated antigen presentation when driven by a prokaryotic promoter. Also, additional Salmonella genes apparently interfere with maintenance of a sustained immune response. Thus, the immunosuppressive yej operon affects innate and adaptive immunity. However, when ST are carriers for eukaryotic-expressed tumor antigens, yej does not severely hamper induction of an immune response.
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Affiliation(s)
- Susanne Hummel
- Department of Tumor Progression and Tumor Defense, German Cancer Research Center, Heidelberg, Germany.
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Chapel H, Puel A, von Bernuth H, Picard C, Casanova JL. Shigella sonnei Meningitis Due to Interleukin-1 Receptor--Associated Kinase--4 Deficiency: First Association with a Primary Immune Deficiency. Clin Infect Dis 2005; 40:1227-31. [PMID: 15825022 DOI: 10.1086/428733] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2004] [Accepted: 11/28/2004] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Inherited interleukin-1-receptor-associated kinase-4 (IRAK-4) deficiency is a recently described immunodeficiency associated with pyogenic bacterial infections and a poor inflammatory response. Shigella sonnei is generally associated with outbreaks of rectocolitis in developed countries, but systemic illnesses have occasionally been reported. An underlying primary immunodeficiency has not been found in such cases before now. METHODS We report the clinical and immunological features of a patient with IRAK-4 deficiency who has a history of systemic shigellosis in addition to other infections. RESULTS The patient has a history of Staphylococcus aureus, Streptococcus pneumoniae, and Pseudomonas aeruginosa infections during childhood and an episode of S. sonnei septicemia and meningitis at 10 years of age. This patient's history contrasted with that of other individuals infected concurrently by the same organism. Of note, these episodes were not accompanied by acute phase responses in our patient. Subsequently, the patient has had more episodes of staphylococcal disease, but no systemic illnesses. The patient is now 30 years old and has been doing well since prophylactic antibiotic treatment was stopped 4 years ago. DISCUSSION To our knowledge, this is the first report of a case of systemic shigellosis in a person with a primary immunodeficiency, expanding the spectrum of infections associated with IRAK-4 deficiency. Thus, immunity mediated by IRAK-4 seems to be crucial for both the containment of and the inflammatory response to S. sonnei infection in the intestinal mucosa. IRAK-4 deficiency and related disorders should be considered in patients with systemic shigellosis.
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Affiliation(s)
- Helen Chapel
- Department of Clinical Immunology, Nuffield Department of Medicine, John Radcliffe Hospital, Headington, Oxford, United Kingdom.
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Pallen MJ, Beatson SA, Bailey CM. Bioinformatics, genomics and evolution of non-flagellar type-III secretion systems: a Darwinian perpective. FEMS Microbiol Rev 2005; 29:201-29. [PMID: 15808742 DOI: 10.1016/j.femsre.2005.01.001] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 12/22/2004] [Accepted: 01/06/2005] [Indexed: 12/17/2022] Open
Abstract
We review the biology of non-flagellar type-III secretion systems from a Darwinian perspective, highlighting the themes of evolution, conservation, variation and decay. The presence of these systems in environmental organisms such as Myxococcus, Desulfovibrio and Verrucomicrobium hints at roles beyond virulence. We review newly discovered sequence homologies (e.g., YopN/TyeA and SepL). We discuss synapomorphies that might be useful in formulating a taxonomy of type-III secretion. The problem of information overload is likely to be ameliorated by launch of a web site devoted to the comparative biology of type-III secretion ().
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Affiliation(s)
- Mark J Pallen
- Bacterial Pathogenesis and Genomics Unit, Division of Immunity and Infection, Medical School, University of Birmingham, Birmingham, West Midlands B15 2TT, UK.
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