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Cain CL, White E, Citron LE, Zheng Q, Morris DO, Grice EA, Bradley CW. Longitudinal evaluation of the cutaneous and rectal microbiota of German shepherd dogs with perianal fistulas undergoing therapy with ciclosporin and ketoconazole. Vet Dermatol 2024; 35:375-385. [PMID: 38616572 DOI: 10.1111/vde.13249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/18/2024] [Accepted: 03/27/2024] [Indexed: 04/16/2024]
Abstract
BACKGROUND Perianal fistulas are painful ulcers or sinus tracts that disproportionately affect German shepherd dogs and are proposed as a spontaneous animal model of fistulising Crohn's disease. OBJECTIVES To characterise the rectal and cutaneous microbiota in German shepherd dogs with perianal fistulas and to investigate longitudinal shifts with lesion resolution during immunomodulatory therapy. ANIMALS Eleven German shepherd dogs with perianal fistulas and 15 healthy German shepherd dogs. MATERIALS AND METHODS Affected dogs were evaluated and swabbed at three visits, 30 days apart, while undergoing treatment with ciclosporin and ketoconazole. Healthy German shepherd dogs were contemporaneously sampled. Sites included the rectum, perianal skin and axilla. The microbiome was evaluated following sequencing of the V4 hypervariable region of the 16S ribosomal RNA (rRNA) gene. RESULTS Alpha diversity was not significantly different between healthy and affected dogs at each of the three body sites (p > 0.5), yet rectal and perianal beta diversities from affected dogs differed significantly from those of healthy dogs at Day 0 (p = 0.004). Rectal and perianal relative abundance of Prevotella spp. increased and perianal Staphylococcus spp. relative abundance decreased in affected dogs over time, coincident with lesion resolution. CONCLUSIONS AND CLINICAL RELEVANCE Changes in lesional cutaneous and rectal microbiota occur in German shepherd dogs with perianal fistulas and shift over time with lesion resolution during immunomodulatory therapy. Further investigations of the role of cutaneous and enteric microbiota in the pathogenesis of perianal fistulas, and whether manipulation of microbial populations may ameliorate disease, are needed.
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Affiliation(s)
- Christine L Cain
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ellen White
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Lindsey E Citron
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Qi Zheng
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Daniel O Morris
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Elizabeth A Grice
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Charles W Bradley
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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The Intersection of Human and Veterinary Medicine-A Possible Direction towards the Improvement of Cell Therapy Protocols in the Treatment of Perianal Fistulas. Int J Mol Sci 2022; 23:ijms232213917. [PMID: 36430390 PMCID: PMC9696944 DOI: 10.3390/ijms232213917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/31/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
The effective treatment of perianal fistulizing Crohn's disease is still a challenge. Local administration of mesenchymal stromal cells (MSCs) is becoming a part of accepted treatment options. However, as a fledgling technique, it still can be optimized. A new trend in translational research, which is in line with "One Health" approach, bases on exploiting parallels between naturally occurring diseases affecting humans and companion animals. Canine anal furunculosis (AF) has been indicated as condition analogous to human perianal Crohn's disease (pCD). This narrative review provides the first comprehensive comparative analysis of these two diseases based on the published data. The paper also outlines the molecular mechanisms of action of MSCs which are likely to have a role in modulating the perianal fistula niche in humans, and refers them to the current knowledge on the immunomodulatory properties of canine MSCs. Generally, the pathogenesis of both diseases shares main determinants such as the presence of genetic predispositions, dysregulation of immune response and the relation to intestine microbiota. However, we also identified many aspects which should be further specified, such as determining the frequency of true fistulas formation in AF patients, elucidating the role of TNF and Th17 pathway in the pathogenesis of AF, or clarifying the role of epithelial-to-mesenchymal transition phenomenon in the formation of canine fistulae. Nevertheless, the available data support the hypothesis that the results from testing cell therapies in dogs with anal furunculosis have a significant translational value in optimizing MSC transplants procedures in pCD patients.
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Novak A, Pupo E, Van't Veld E, Rutten VPMG, Broere F, Sloots A. Activation of Canine, Mouse and Human TLR2 and TLR4 by Inactivated Leptospira Vaccine Strains. Front Immunol 2022; 13:823058. [PMID: 35386703 PMCID: PMC8978998 DOI: 10.3389/fimmu.2022.823058] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/28/2022] [Indexed: 12/31/2022] Open
Abstract
Canine Leptospira vaccines contain inactivated strains of pathogenic Leptospira, the causative agents of leptospirosis. For an effective response to vaccination, activation of the innate immune system via pattern recognition receptors such as TLRs is crucial. However, it is not known which TLRs are activated by Leptospira in dogs. To investigate the involvement of canine TLR2, TLR4, and TLR5 in the recognition of Leptospira, we stimulated canine moDC and reporter cells expressing canine TLR2 with either whole-inactivated bacteria or purified LPS of Leptospira strains, representing the serogroups generally used in canine leptospirosis vaccines. Using the endotoxin neutralizing reagent polymyxin B and TLR4 antagonist RS-LPS, we demonstrate that Leptospira LPS and canine TLR4 are involved in IL-1β production as well as in the uptake of inactivated Leptospira in canine moDC. Furthermore, polymyxin B only partially inhibited IL-1β production induced by inactivated Leptospira, suggesting that next to TLR4, also other TLRs may be involved. The observed activation of canine TLR2-expressing reporter cells by inactivated Leptospira strains indicates that TLR2 could be one of these TLRs. Next, we analyzed TLR2 and TLR4 activating capabilities by the same Leptospira strains using human and mouse TLR-expressing reporter cells. Inactivated Leptospira and leptospiral LPS activated not only mouse, but also human TLR4 and this activation was shown to be LPS dependent in both cases. Additionally, inactivated Leptospira activated mouse and human TLR2-expressing reporter cell lines. In our study, we could not identify significant species differences in the recognition of Leptospira by TLR2 and TLR4 between dog, human and mouse. Lastly, we show that these inactivated Leptospira strains are recognized by both mouse and human TLR5 reporter cells only after exposure to additional heat-treatment. Unfortunately, we were not able to confirm this in the canine system. Our data show that TLR2 and TLR4 are involved in the recognition of Leptospira strains used in the production of canine Leptospira vaccines. This study contributes to the understanding of Leptospira-induced innate immune responses in dogs, humans, and mice. Future studies are needed to further explore the role of canine TLR2, TLR4 and TLR5 in the induction of vaccine-mediated immunity against Leptospira.
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Affiliation(s)
- Andreja Novak
- Division Infectious Diseases and Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Department of Product Characterization and Formulation, Intravacc, Bilthoven, Netherlands
| | - Elder Pupo
- Department of Product Characterization and Formulation, Intravacc, Bilthoven, Netherlands
| | - Esther Van't Veld
- Center for Cell Imaging (CCI), Division Cell Biology, Metabolism and Cancer, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Victor P M G Rutten
- Division Infectious Diseases and Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - Femke Broere
- Division Infectious Diseases and Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Division Internal Medicine of Companion Animals, Department Clinical Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Arjen Sloots
- Department of Product Characterization and Formulation, Intravacc, Bilthoven, Netherlands
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Kloch A, Biedrzycka A, Szewczyk M, Nowak S, Niedźwiedzka N, Kłodawska M, Hájková A, Hulva P, Jędrzejewska B, Mysłajek R. High genetic diversity of immunity genes in an expanding population of a highly mobile carnivore, the grey wolf
Canis
lupus
, in Central Europe. DIVERS DISTRIB 2021. [DOI: 10.1111/ddi.13360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Agnieszka Kloch
- Department of Ecology, Institute of Functional Biology and Ecology, Faculty of Biology, Biological and Chemical Research Centre University of Warsaw Warszawa Poland
| | | | - Maciej Szewczyk
- Department of Vertebrate Ecology and Zoology Faculty of Biology University of Gdańsk Gdańsk Poland
| | - Sabina Nowak
- Association for Nature “Wolf” Twardorzeczka Poland
| | | | - Monika Kłodawska
- Department of Zoology Faculty of Science Charles University Prague Czech Republic
| | - Andrea Hájková
- State Nature Conservancy of the Slovak Republic Spišská Nová Ves Slovakia
| | - Pavel Hulva
- Department of Zoology Faculty of Science Charles University Prague Czech Republic
- Department of Biology and Ecology Faculty of Science University of Ostrava Ostrava Czech Republic
| | | | - Robert Mysłajek
- Department of Ecology, Institute of Functional Biology and Ecology, Faculty of Biology, Biological and Chemical Research Centre University of Warsaw Warszawa Poland
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Igarashi H, Ohno K, Uchida E, Fujiwara-Igarashi A, Kanemoto H, Fukushima K, Uchida K, Tsujimoto H. Polymorphisms of nucleotide-binding oligomerization domain 2 (NOD2) gene in miniature dachshunds with inflammatory colorectal polyps. Vet Immunol Immunopathol 2015; 164:160-9. [PMID: 25746347 DOI: 10.1016/j.vetimm.2015.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/01/2015] [Accepted: 02/11/2015] [Indexed: 12/18/2022]
Abstract
Inflammatory colorectal polyps (ICRPs) frequently occur in miniature dachshunds (MDs) in Japan, typically form multiple polyps with severe neutrophil infiltration. ICRPs are speculated as a novel, breed-specific canine inflammatory bowel disease. Pattern recognition receptors (PRRs) play an important role in the differentiation of pathogens from commensal bacteria and food antigens, and polymorphisms of various PRRs have been shown to be associated with human and canine IBD. We recently reported that the reactivity of nucleotide-binding oligomerization domain 2 (NOD2), toll-like receptor (TLR) 1/2, TLR2, and TLR2/6 are greater in ICRP-affected MDs than that in controls. Therefore, this study was aimed to investigate single nucleotide polymorphisms (SNPs) of PRRs associated with ICRPs in MDs. Mutational analysis of canine NOD2, TLR1, TLR2, and TLR6 genes was performed with six ICRP-affected MDs, five control MDs, and five healthy beagles. The mutational analysis identified 13 non-synonymous SNPs in NOD2, TLR1, TLR2, and TLR6 genes, of which six SNPs in NOD2 exon 3 were further analyzed in an association study using 63 ICRP-affected MDs, 82 control MDs, and 237 control dogs of various breeds. Four of the SNPs (A1532G, T1573C, C1688G, and G1880A of the NOD2 gene) were in Hardy-Weinberg equilibrium and in complete linkage disequilibrium in MDs, and their minor allele frequencies were significantly lower in ICRP-affected MDs than in control MDs (0.016 vs. 0.140, P=0.0002). The calculated inheritance model was an additive model (odds ratio=0.10, 95% confidence interval=0.02-0.45, P=0.0001), which indicates that the haplotype with minor alleles in these SNPs (A, T, C, and G in A1532G, T1573C, C1688G, and G1880A) possess a protective effect regarding the development of ICRPs. However, these SNPs were not specific for MDs, although the minor allele frequencies of these SNPs in control MDs were significantly lower than in other breed dogs. These results suggest that the identified four SNPs (A1532G, T1573C, C1688G, and G1880A in the NOD2 gene) may play a role in the pathogenesis of ICRPs in MDs. Because the majority of MDs and other breed dogs do not have the protective alleles, their absence may not be a specific cause of ICRPs in MDs but rather contribute to the development of inflammation.
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Affiliation(s)
- Hirotaka Igarashi
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Koichi Ohno
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
| | - Eri Uchida
- Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Aki Fujiwara-Igarashi
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hideyuki Kanemoto
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Kenjiro Fukushima
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Kazuyuki Uchida
- Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hajime Tsujimoto
- Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Genetics of canine anal furunculosis in the German shepherd dog. Immunogenetics 2014; 66:311-24. [DOI: 10.1007/s00251-014-0766-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 02/25/2014] [Indexed: 12/25/2022]
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Prélaud AR, Fuchs S, Weber K, Winter G, Coester C, Mueller RS. In vitro effects of CpG oligodeoxynucleotides delivered by gelatin nanoparticles on canine peripheral blood mononuclear cells of atopic and healthy dogs - a pilot study. Vet Dermatol 2013; 24:494-e117. [PMID: 23826658 DOI: 10.1111/vde.12056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND Cytosine-phosphate-guanine (CpG) oligodeoxynucleotides offer a novel promising immunotherapeutic approach for atopic dermatitis (AD) both in humans and animals. Gelatin nanoparticles (GNP) enhance and prolong CpG-associated immunomodulatory effects and minimize adverse effects both in vitro and in vivo. Information about the effects of this combination in dogs is lacking. HYPOTHESIS/OBJECTIVES The aim of this study was to evaluate immunological effects of CpG coupled to GNP on canine peripheral blood mononuclear cells (PBMCs) in vitro. ANIMALS Eight dogs with AD, diagnosed by standard criteria and with a concurrent immediate hypersensitivity to house dust mites were included. Control samples were taken from eight healthy, age-matched control dogs without history or evidence of cutaneous or systemic illness. METHODS Peripheral blood mononuclear cells of healthy and allergic dogs were incubated with CpG-GNP and the uptake of CpG-GNP was demonstrated using confocal laser scanning microscopy. Cell culture supernatant concentrations of interferon gamma (IFN-γ), interleukin (IL)-4, IL-6 and IL-10 were measured by Canine Cytokine Milliplex. RESULTS No significant changes in IFN-γ and IL-4 were found when comparing PBMCs incubated with CpG and CpG-GNP with the negative controls in atopic and healthy dogs. Interleukin-6 was not detected in any of the groups. However, a statistically significant increase in IL-10 concentration was found after 24 h stimulation with CpG-GNP compared with CpG alone both in atopic and healthy dogs. CONCLUSIONS AND CLINICAL IMPORTANCE As IL-10 is considered an immunosuppressive cytokine playing a key role in peripheral tolerance; the reported CpG-GNP formulation could be a new approach in allergy treatment.
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Affiliation(s)
- Ana Rostaher Prélaud
- Vetsuisse Faculty University of Zurich, Clinic for Small Animal Internal Medicine, 8057, Zurich, Switzerland; Small Animal Medicine Clinic, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University, 80539, Munich, Germany
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Okanishi H, Hayashi K, Sakamoto Y, Sano T, Maruyama H, Kagawa Y, Watari T. NOD2 mRNA Expression and NFkappaB Activation in Dogs with Lymphocytic Plasmacytic Colitis. J Vet Intern Med 2013; 27:439-44. [DOI: 10.1111/jvim.12082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 02/02/2013] [Accepted: 03/05/2013] [Indexed: 12/15/2022] Open
Affiliation(s)
- H. Okanishi
- Laboratory of Comprehensive Veterinary Clinical Studies
| | - K. Hayashi
- Laboratory of Comprehensive Veterinary Clinical Studies
| | - Y. Sakamoto
- Laboratory of Comprehensive Veterinary Clinical Studies
| | - T. Sano
- Laboratory of Comprehensive Veterinary Clinical Studies
| | - H. Maruyama
- Laboratory of Veterinary Pathobiology (Maruyama); Department of Veterinary Medicine; College of Bioresource Sciences; Nihon University; Kanagawa Japan
| | | | - T. Watari
- Laboratory of Comprehensive Veterinary Clinical Studies
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11
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Lewis D, Chan D, Pinheiro D, Armitage‐Chan E, Garden O. The immunopathology of sepsis: pathogen recognition, systemic inflammation, the compensatory anti-inflammatory response, and regulatory T cells. J Vet Intern Med 2012; 26:457-82. [PMID: 22428780 PMCID: PMC7166777 DOI: 10.1111/j.1939-1676.2012.00905.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 11/28/2011] [Accepted: 02/07/2012] [Indexed: 02/06/2023] Open
Abstract
Sepsis, the systemic inflammatory response to infection, represents the major cause of death in critically ill veterinary patients. Whereas important advances in our understanding of the pathophysiology of this syndrome have been made, much remains to be elucidated. There is general agreement on the key interaction between pathogen-associated molecular patterns and cells of the innate immune system, and the amplification of the host response generated by pro-inflammatory cytokines. More recently, the concept of immunoparalysis in sepsis has also been advanced, together with an increasing recognition of the interplay between regulatory T cells and the innate immune response. However, the heterogeneous nature of this syndrome and the difficulty of modeling it in vitro or in vivo has both frustrated the advancement of new therapies and emphasized the continuing importance of patient-based clinical research in this area of human and veterinary medicine.
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Affiliation(s)
- D.H. Lewis
- Department of Veterinary Clinical SciencesThe Royal Veterinary CollegeHatfield CampusHertfordshire,UK (Lewis, Chan, Garden)
- Present address:
Langford Veterinary ServicesSmall Animal HospitalLangford HouseLangfordBristol, BS40 5DUUK
| | - D.L. Chan
- Department of Veterinary Clinical SciencesThe Royal Veterinary CollegeHatfield CampusHertfordshire,UK (Lewis, Chan, Garden)
| | - D. Pinheiro
- Regulatory T Cell LaboratoryThe Royal Veterinary CollegeCamden Campus, LondonNW1 OTUUK (Pinheiro, Garden)
| | - E. Armitage‐Chan
- Davies Veterinary SpecialistsManor Farm Business ParkHertfordshireSG5 3HR, UK (Armitage‐Chan)
| | - O.A. Garden
- Department of Veterinary Clinical SciencesThe Royal Veterinary CollegeHatfield CampusHertfordshire,UK (Lewis, Chan, Garden)
- Regulatory T Cell LaboratoryThe Royal Veterinary CollegeCamden Campus, LondonNW1 OTUUK (Pinheiro, Garden)
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Catchpole B, Allenspach K. Canine inflammatory bowel disease: does innate immunity fail to discriminate between friend and foe? Vet J 2012; 194:7-8. [PMID: 22513299 DOI: 10.1016/j.tvjl.2012.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 03/13/2012] [Indexed: 01/24/2023]
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Kathrani A, House A, Catchpole B, Murphy A, German A, Werling D, Allenspach K. Polymorphisms in the TLR4 and TLR5 gene are significantly associated with inflammatory bowel disease in German shepherd dogs. PLoS One 2010; 5:e15740. [PMID: 21203467 PMCID: PMC3009732 DOI: 10.1371/journal.pone.0015740] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 11/22/2010] [Indexed: 01/08/2023] Open
Abstract
Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease.
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Affiliation(s)
- Aarti Kathrani
- Department of Veterinary Clinical Sciences, Royal Veterinary College, University of London, Hatfield, United Kingdom.
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