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Mechanisms involved in the adaptation of Escherichia coli O157:H7 to the host intestinal microenvironment. Clin Sci (Lond) 2020; 134:3283-3301. [PMID: 33346356 DOI: 10.1042/cs20200971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 11/17/2022]
Abstract
Host adaptation of pathogens may increase intra- and interspecies transmission. We showed previously that the passage of a clinically isolated enterohemorrhagic Escherichia coli (EHEC) O157 strain (125/99) through the gastrointestinal tract of mice increases its pathogenicity in the same host. In this work, we aimed to elucidate the underlying mechanism(s) involved in the patho-adaptation of the stool-recovered (125RR) strain. We assessed the global transcription profile by microarray and found almost 100 differentially expressed genes in 125RR strain compared with 125/99 strain. We detected an overexpression of Type Three Secretion System (TTSS) proteins at the mRNA and protein levels and demonstrated increased adhesion to epithelial cell lines for the 125RR strain. Additional key attributes of the 125RR strain were: increased motility on semisolid agar, which correlated with an increased fliC mRNA level; reduced Stx2 production at the mRNA and protein levels; increased survival at pH 2.5, as determined by acid resistance assays. We tested whether the overexpression of the LEE-encoded regulator (ler) in trans in the 125/99 strain could recreate the increased pathogenicity observed in the 125RR strain. As anticipated ler overexpression led to increased expression of TTSS proteins and bacterial adhesion to epithelial cells in vitro but also increased mortality and intestinal colonization in vivo. We conclude that this host-adaptation process required changes in several mechanisms that improved EHEC O157 fitness in the new host. The research highlights some of the bacterial mechanisms required for horizontal transmission of these zoonotic pathogens between their animal and human populations.
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Junaid QO, Khaw LT, Mahmud R, Ong KC, Lau YL, Borade PU, Liew JWK, Sivanandam S, Wong KT, Vythilingam I. Pathogenesis of Plasmodium berghei ANKA infection in the gerbil (Meriones unguiculatus) as an experimental model for severe malaria. ACTA ACUST UNITED AC 2017; 24:38. [PMID: 29034874 PMCID: PMC5642054 DOI: 10.1051/parasite/2017040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/26/2017] [Indexed: 01/10/2023]
Abstract
Background: As the quest to eradicate malaria continues, there remains a need to gain further understanding of the disease, particularly with regard to pathogenesis. This is facilitated, apart from in vitro and clinical studies, mainly via in vivo mouse model studies. However, there are few studies that have used gerbils (Meriones unguiculatus) as animal models. Thus, this study is aimed at characterizing the effects of Plasmodium berghei ANKA (PbA) infection in gerbils, as well as the underlying pathogenesis. Methods: Gerbils, 5-7 weeks old were infected by PbA via intraperitoneal injection of 1 × 106 (0.2 mL) infected red blood cells. Parasitemia, weight gain/loss, hemoglobin concentration, red blood cell count and body temperature changes in both control and infected groups were monitored over a duration of 13 days. RNA was extracted from the brain, spleen and whole blood to assess the immune response to PbA infection. Organs including the brain, spleen, heart, liver, kidneys and lungs were removed aseptically for histopathology. Results: Gerbils were susceptible to PbA infection, showing significant decreases in the hemoglobin concentration, RBC counts, body weights and body temperature, over the course of the infection. There were no neurological signs observed. Both pro-inflammatory (IFNγ and TNF) and anti-inflammatory (IL-10) cytokines were significantly elevated. Splenomegaly and hepatomegaly were also observed. PbA parasitized RBCs were observed in the organs, using routine light microscopy and in situ hybridization. Conclusion: Gerbils may serve as a good model for severe malaria to further understand its pathogenesis.
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Affiliation(s)
- Quazim Olawale Junaid
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia - Department of Biological Science, Faculty of Science, Federal University Kashere, Gombe State, Nigeria
| | - Loke Tim Khaw
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia - Department of Pathology, School of Medicine, International Medical University, 57000 Kuala Lumpur, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Prajakta Uttam Borade
- Department of Pathology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Jonathan Wee Kent Liew
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Sinnadurai Sivanandam
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Kum Thong Wong
- Department of Pathology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
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Silva WM, Carvalho RDDO, Dorella FA, Folador EL, Souza GHMF, Pimenta AMC, Figueiredo HCP, Le Loir Y, Silva A, Azevedo V. Quantitative Proteomic Analysis Reveals Changes in the Benchmark Corynebacterium pseudotuberculosis Biovar Equi Exoproteome after Passage in a Murine Host. Front Cell Infect Microbiol 2017; 7:325. [PMID: 28791255 PMCID: PMC5524672 DOI: 10.3389/fcimb.2017.00325] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 07/03/2017] [Indexed: 11/13/2022] Open
Abstract
Corynebacterium pseudotuberculosis biovar equi is the etiologic agent of ulcerative lymphangitis. To investigate proteins that could be related to the virulence of this pathogen, we combined an experimental passage process using a murine model and high-throughput proteomics with a mass spectrometry, data-independent acquisition (LC-MSE) approach to identify and quantify the proteins released into the supernatants of strain 258_equi. To our knowledge, this approach allowed characterization of the exoproteome of a C. pseudotuberculosis equi strain for the first time. Interestingly, the recovery of this strain from infected mouse spleens induced a change in its virulence potential, and it became more virulent in a second infection challenge. Proteomic screening performed from culture supernatant of the control and recovered conditions revealed 104 proteins that were differentially expressed between the two conditions. In this context, proteomic analysis of the recovered condition detected the induction of proteins involved in bacterial pathogenesis, mainly related to iron uptake. In addition, KEGG enrichment analysis showed that ABC transporters, bacterial secretion systems and protein export pathways were significantly altered in the recovered condition. These findings show that secretion and secreted proteins are key elements in the virulence and adaptation of C. pseudotuberculosis. Collectively, bacterial pathogenesis-related proteins were identified that contribute to the processes of adherence, intracellular growth and evasion of the immune system. Moreover, this study enhances our understanding of the factors that may influence the pathogenesis of C. pseudotuberculosis.
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Affiliation(s)
- Wanderson M Silva
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo Horizonte, Brazil.,Institut National de la Recherche Agronomique (INRA), UMR1253 Science & Technologie du Lait & de l'Oeuf (STLO)Rennes, France.,Agrocampus Ouest, UMR1253 Science & Technologie du Lait & de l'Oeuf (STLO)Rennes, France
| | - Rodrigo D De Oliveira Carvalho
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Fernanda A Dorella
- Escola de Veterinária, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Edson L Folador
- Centro de Biotecnologia, Universidade Federal da ParaíbaJoão Pessoa, Brazil
| | - Gustavo H M F Souza
- Waters Corporation, Waters Technologies Brazil, MS Applications LaboratorySão Paulo, Brazil
| | - Adriano M C Pimenta
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | | | - Yves Le Loir
- Institut National de la Recherche Agronomique (INRA), UMR1253 Science & Technologie du Lait & de l'Oeuf (STLO)Rennes, France.,Agrocampus Ouest, UMR1253 Science & Technologie du Lait & de l'Oeuf (STLO)Rennes, France
| | - Artur Silva
- Instituto de Ciências Biológicas, Universidade Federal do ParáBelém, Brazil
| | - Vasco Azevedo
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
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Silva WM, Dorella FA, Soares SC, Souza GHMF, Castro TLP, Seyffert N, Figueiredo H, Miyoshi A, Le Loir Y, Silva A, Azevedo V. A shift in the virulence potential of Corynebacterium pseudotuberculosis biovar ovis after passage in a murine host demonstrated through comparative proteomics. BMC Microbiol 2017; 17:55. [PMID: 28327085 PMCID: PMC5361795 DOI: 10.1186/s12866-017-0925-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 01/04/2017] [Indexed: 01/19/2023] Open
Abstract
Background Corynebacterium pseudotuberculosis biovar ovis, a facultative intracellular pathogen, is the etiologic agent of caseous lymphadenitis in small ruminants. During the infection process, C. pseudotuberculosis changes its gene expression to resist different types of stresses and to evade the immune system of the host. However, factors contributing to the infectious process of this pathogen are still poorly documented. To better understand the C. pseudotuberculosis infection process and to identify potential factors which could be involved in its virulence, experimental infection was carried out in a murine model using the strain 1002_ovis and followed by a comparative proteomic analysis of the strain before and after passage. Results The experimental infection assays revealed that strain 1002_ovis exhibits low virulence potential. However, the strain recovered from the spleen of infected mice and used in a new infection challenge showed a dramatic change in its virulence potential. Label-free proteomic analysis of the culture supernatants of strain 1002_ovis before and after passage in mice revealed that 118 proteins were differentially expressed. The proteome exclusive to the recovered strain contained important virulence factors such as CP40 proteinase and phospholipase D exotoxin, the major virulence factor of C. pseudotuberculosis. Also, the proteome from recovered condition revealed different classes of proteins involved in detoxification processes, pathogenesis and export pathways, indicating the presence of distinct mechanisms that could contribute in the infectious process of this pathogen. Conclusions This study shows that C. pseudotuberculosis modifies its proteomic profile in the laboratory versus infection conditions and adapts to the host context during the infection process. The screening proteomic performed us enable identify known virulence factors, as well as potential proteins that could be related to virulence this pathogen. These results enhance our understanding of the factors that might influence in the virulence of C. pseudotuberculosis. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-0925-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wanderson M Silva
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.,INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Fernanda A Dorella
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Siomar C Soares
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Gustavo H M F Souza
- Waters Corporation, Waters Technologies Brazil, MS Applications Laboratory, Alphaville, São Paulo, Brazil
| | - Thiago L P Castro
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Núbia Seyffert
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Henrique Figueiredo
- Aquacen, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Anderson Miyoshi
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Yves Le Loir
- INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Artur Silva
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, Belém, Pará, Brazil
| | - Vasco Azevedo
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
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Role of energy sensor TlpD of Helicobacter pylori in gerbil colonization and genome analyses after adaptation in the gerbil. Infect Immun 2013; 81:3534-51. [PMID: 23836820 DOI: 10.1128/iai.00750-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Helicobacter pylori maintains colonization in its human host using a limited set of taxis sensors. TlpD is a proposed energy taxis sensor of H. pylori and dominant under environmental conditions of low bacterial energy yield. We studied the impact of H. pylori TlpD on colonization in vivo using a gerbil infection model which closely mimics the gastric physiology of humans. A gerbil-adapted H. pylori strain, HP87 P7, showed energy-dependent behavior, while its isogenic tlpD mutant lost it. A TlpD-complemented strain regained the wild-type phenotype. Infection of gerbils with the complemented strain demonstrated that TlpD is important for persistent infection in the antrum and corpus and suggested a role of TlpD in horizontal navigation and persistent corpus colonization. As a part of the full characterization of the model and to gain insight into the genetic basis of H. pylori adaptation to the gerbil, we determined the complete genome sequences of the gerbil-adapted strain HP87 P7, two HP87 P7 tlpD mutants before and after gerbil passage, and the original human isolate, HP87. The integrity of the genome, including that of a functional cag pathogenicity island, was maintained after gerbil adaptation. Genetic and phenotypic differences between the strains were observed. Major differences between the gerbil-adapted strain and the human isolate emerged, including evidence of recent recombination. Passage of the tlpD mutant through the gerbil selected for gain-of-function variation in a fucosyltransferase gene, futC (HP0093). In conclusion, a gerbil-adapted H. pylori strain with a stable genome has helped to establish that TlpD has important functions for persistent colonization in the stomach.
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Bleich EM, Keubler LM, Smoczek A, Mähler M, Bleich A. Hygienic monitoring of Mongolian gerbils: which mouse viruses should be included? Lab Anim 2012; 46:173-5. [PMID: 22334874 DOI: 10.1258/la.2011.011144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Mongolian gerbil (Meriones unguiculatus) serves as an animal model for a wide range of diseases. A practical limitation in its use is the definition of the hygienic status, as not much is known about viruses that potentially infect gerbils and might be transmitted to other rodents. As successful re-derivation was recently described for gerbils, we now aimed at investigating which mouse viruses induce seroconversion in gerbils and might be transmitted to mice. Gerbils were inoculated with viral agents of mice and co-housed with mouse contact sentinels. Seroconversion in gerbils was observed after oronasal inoculation with Sendai virus (SeV), mammalian orthoreovirus serotype 3 (Reo-3) and rotavirus A (RV-A, EDIM), seroconversion to RV-A also in sentinel mice. Pneumonia virus of mice (PVM) was not detected by serology but by polymerase chain reaction in gerbils and respective sentinel mice. No seroconversion towards or transmission of murine hepatitis virus, murine norovirus, minute virus of mice or mouse cytomegalovirus was detected. Anti-gerbil IgG antibodies did not increase sensitivity of indirect immunofluorescence (IFA) compared with anti-mouse IgG. In conclusion, seroconversion to SeV, Reo-3 and RV-A as well as transmission of RV-A and PVM indicate that these agents should be included in health monitoring of gerbils. Furthermore, anti-mouse IgG is suitable as a secondary antibody for IFA with gerbil serum.
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Affiliation(s)
- Eva-M Bleich
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, 30625 Hannover, Germany.
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Zárate-Aquino C, Torres-Marcial J, Ortiz-Herrera M, Romero-Ramírez H, Santos-Argumedo L, López-Corella E, Coria-Jiménez R. Identification of Helicobacter pylori strain cagPAI+ and cagPAI- Antigens by IgG antibodies from sera of experimentally colonized meriones unguiculatus (Mongolian gerbils). Helicobacter 2011; 16:200-9. [PMID: 21585605 DOI: 10.1111/j.1523-5378.2011.00831.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Mongolian gerbils that are experimentally infected with Helicobacter pylori develop a chronic inflammation that is similar to natural infections in humans. The aim of this study was to compare the antigens of H. pylori cagPAI+ and cagPAI- strains that are expressed during Meriones unguiculatus colonization. MATERIALS AND METHODS We identified H. pylori cagPAI+ and cagPAI- strain antigens via Western blotting of samples from Mongolian gerbils that were subjected to unique, mixed, and sequential bacterial infections. RESULTS The antigens from the J99/CG3 (cagPAI+) strain had a lower molecular weight than the antigens from the 251F/CG3 (cagPAI-) strain. There were fewer identified antigens in the single unique infections compared with the mixed and sequential infections. The number of recognized antigens that had a frequency of recognition >60% was higher for the simultaneous and sequential infection groups compared with the single infection group. A 57-kDa antigen was present in >60% of the samples and four of the five experimental groups. Antigens specific to each bacterial strain were identified; the 190- and 158-kDa antigens appear to be specific for cagPAI-, and the 70-kDa antigen appears to be specific for cagPAI+. CONCLUSIONS In this study, we identified antigens that are common and specific to the H. pylori cagPAI+ and cagPAI- strains.
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Affiliation(s)
- Carmen Zárate-Aquino
- Laboratory of Experimental Bacteriology, National Institute of Pediatrics, Mexico City, Mexico
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Study of simultaneous experimental colonization of Meriones unguiculatus (Mongolian gerbils) by cagPAI+ and cagPAI− strains of Helicobacter pylori. Microbes Infect 2010; 12:607-14. [DOI: 10.1016/j.micinf.2010.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 03/07/2010] [Accepted: 04/08/2010] [Indexed: 01/17/2023]
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Bleich EM, Martin M, Bleich A, Klos A. The Mongolian gerbil as a model for inflammatory bowel disease. Int J Exp Pathol 2010; 91:281-7. [PMID: 20113376 DOI: 10.1111/j.1365-2613.2009.00701.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Mongolian gerbils are used as biomedical research models for a variety of diseases and are in some cases suited better than other rodents for basic research and therapeutic studies. The aim of this study was to establish and characterize a dextran sulphate sodium (DSS)-induced model in gerbils for the human inflammatory bowel disease (IBD) and to utilize them for a therapeutic study in vivo. Four concentrations (0.5%, 1%, 2% and 4%) of DSS were administered via drinking water for 7 days; based on these results, a concentration of 3% DSS was given for 9 days in a second approach. Fluid uptake and general clinical condition were assessed daily using a clinical score. Caecum and colon were scored histologically. Fluid uptake was affected by addition of DSS to the drinking water. First clinical symptoms were observed at day 4 of DSS treatment with a considerable increase in clinical score parameters only in gerbils receiving 2% or 4% DSS. Histologically, ulceration and inflammation were observed predominantly in the caecum of gerbils treated with at least 1% DSS; reproducible inflammation in the colon required at least 2% DSS. Using 3% DSS for 9 days, considerably more inflammation was induced in the colon, comparable with lesions usually observed in the mouse model. Using an optimized protocol, DSS treatment induces reproducibly typhlocolitis in Mongolian gerbils, rendering them as a useful model for IBD.
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Affiliation(s)
- Eva-Maria Bleich
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover, Germany
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Guo G, Liu KY, Xie QH, Zhang WJ, Zou QM. Establishment of a BALB/c mouse model infected steadily with H. pylori through serial passages in vivo. Shijie Huaren Xiaohua Zazhi 2007; 15:1338-1341. [DOI: 10.11569/wcjd.v15.i12.1338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To increase the colonization ability of H. pylori and establish a BALB/c mouse model infected steadily with H. pylori.
METHODS: Mongolian gerbils-adaptive strain GS10 of H. pylori were inoculated into BALB/c mice and acclimated through serial passages in vivo for procuring an adaptive colonization of H. pylori strain. After being infected for 4 weeks, all the animals were treated for microbiological examination, including culturing, smearing, urease test and polymerase chain reaction (PCR). The infectious rate of each group was calculated till the rate rose to 80%. Then, the gastric mucosal tissues were collected from the infected mice for quantitative analysis of H. pylori and histological examination.
RESULTS: The proportion of BALB/c mice infected by H. pylori increased gradually from about 11.1% at the first infection to 80% after 6 passages in vivo. At the 4th week after BALB/c mice were infected with the adaptive strain BS8 (strains after 8 passages), the colonization density in the gastric antrum, body and fundus of the infected mice, expressed by the common logarithm of colony forming unit per gram of tissue, was 5.03 ± 1.16, 4.27 ± 0.93 and 0.72 ± 2.57, respectively, which were similar to the colonization density (5.32 ± 0.88, 4.14 ± 1.05 and 1.05 ± 2.25) in the mice infected with H. pylori strain SS1 (P > 0.05). Infiltrations of polymorphonuclear leucocytes and monomuclear cells were observed in the lamina propria and submucosa of the stomach from the H. pylori-infected mice. A great number of H. pylori were also observed in the gastric mucus through microscopy.
CONCLUSION: H. pylori with high colonization ability and infection rates are obtained, and a BALB/c mouse model infected steadily with H. pylori is established successfully.
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Bleich A, Mahler M. Environment as a Critical Factor for the Pathogenesis and Outcome of Gastrointestinal Disease: Experimental and Human Inflammatory Bowel Disease and Helicobacter-Induced Gastritis. Pathobiology 2006; 72:293-307. [PMID: 16582581 DOI: 10.1159/000091327] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 10/18/2005] [Indexed: 12/20/2022] Open
Abstract
Environmental factors play an important role in the manifestation, course, and prognosis of diseases of the gastrointestinal tract such as inflammatory bowel disease (IBD) and Helicobacter pylori-induced gastritis. These two disease complexes were chosen for a discussion of the contribution of environmental factors to the disease outcome in humans and animal models. Dissecting complex diseases like IBD and Helicobacter-induced gastritis has shown that the outcome of disease depends on the allelic constellation of a host and the microbial and physical environments. Host alleles predisposing to a disease in one genomic and/or environmental milieu may not be deleterious in other constellations; on the other hand, microbes can have different effects in different hosts and under different environmental conditions. The impact of the complex interaction between host genetics and environmental factors, particularly microflora, also underlines the importance of a defined genetic background and defined environments in animal studies and is indicative of the difficulties in analyzing complex diseases in humans.
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Affiliation(s)
- A Bleich
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, Hannover, Germany.
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