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Zhu YW, Liu ZT, Tang AQ, Liang X, Wang Y, Liu YF, Jin YQ, Gao W, Yuan H, Wang DY, Ji X, Wu D. The emerging roles of hydrogen sulfide in ferroptosis. Antioxid Redox Signal 2024. [PMID: 39041626 DOI: 10.1089/ars.2023.0535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
SIGNIFICANCE Ferroptosis, a form of regulated cell death characterized by a large amount of lipid peroxidation-mediated membrane damage, joins the evolution of multisystem diseases. For instance, neurodegenerative diseases, chronic obstructive pulmonary disease and acute respiratory distress syndrome, osteoporosis and osteoarthritis, and so on. Since being identified as the third gasotransmitter in living organisms, the intricate role of hydrogen sulfide (H2S) in ferroptosis has emerged at the forefront of research. RECENT ADVANCES The discovery of novel targets in the relevant metabolic pathways, including transferrin receptor 1, cystine/glutamate antiporter, and others, coupled with the exploration of new signaling pathways, particularly the p53 signaling pathway and the nitric oxide / nuclear factor erythroid 2-related factor 2 signaling pathway, and so on. Many diseases such as emphysema and airway inflammation, myocardial diseases, endothelial dysfunction in aging arteries, and traumatic brain injury have recently been found to be alleviated directly by H2S inhibition of ferroptosis. Safe, effective, and tolerable novel H2S donors have been developed and have shown promising results in phase I clinical trials. CRITICAL ISSUES Complicated crosstalk between ferroptosis signaling pathway and oncogenic factors results in the risk of cancer when inhibiting ferroptosis. Notably, targeted delivery of H2S is still a challenging task. FUTURE DIRECTIONS Discovering more reliable and stable novel H2S donors and achieving their targeted delivery will enable further clinical trials for diseases associated with ferroptosis inhibition by H2S, determining their safety, efficacy, and tolerance.
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Affiliation(s)
- Yi-Wen Zhu
- Henan University, Kaifeng, Henan, China;
| | - Zi-Tao Liu
- Henan University, Kaifeng, Henan, China;
| | - Ao-Qi Tang
- Henan University, Kaifeng, Henan, China;
| | - Xiaoyi Liang
- Henan University, North section Jinming Avenue, Kaifeng, None Selected, China, 475001;
| | - Yan Wang
- Henan University, Kaifeng, Henan, China;
| | | | | | - Wei Gao
- Henan University, Kaifeng, Henan, China;
| | - Hang Yuan
- Henan University, Kaifeng, Henan, China;
| | | | | | - DongDong Wu
- Henan University, North section of Jinming Dadao, Kaifeng City, Henan Province, Kaifeng, China, 475001;
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Megat Mazhar Khair MH, Selvarajah GT, Omar AR, Mustaffa-Kamal F. Expression of Toll-like receptors 3, 7, 9 and cytokines gene expression in feline infectious peritonitis virus-infected CRFK cells and feline peripheral monocytes. J Vet Sci 2022; 23:e27. [PMID: 35363438 PMCID: PMC8977543 DOI: 10.4142/jvs.21225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/04/2021] [Accepted: 11/29/2021] [Indexed: 11/28/2022] Open
Abstract
Background The role of Toll-like receptors (TLRs) in a feline infectious peritonitis virus (FIPV) infection is not completely understood. Objectives This study examined the expression of TLR3, TLR7, TLR9, tumor necrosis factor-alpha (TNF-α), interferon (IFN)-β, and interleukin (IL)-10 upon an FIPV infection in Crandell-Reese feline kidney (CRFK) cells and feline monocytes. Methods CRFK cells and monocytes from feline coronavirus (FCoV)-seronegative cats and FCoV-seropositive cats were infected with type II FIPV-79-1146. At four, 12, and 24 hours post-infection (hpi), the expression of TLR3, TLR7, TLR9, TNF-α, IFN-β, and IL-10, and the viral load were measured using reverse transcription quantitative polymerase chain reaction. Viral protein production was confirmed using immunofluorescence. Results FIPV-infected CRFK showed the upregulation of TLR9, TNF-α, and IFN-β expression between 4 and 24 hpi. Uninfected monocytes from FCoV-seropositive cats showed lower TLR3 and TLR9 expression but higher TLR7 expression compared to uninfected monocytes from FCoV-seronegative cats. FIPV-infected monocytes from FCoV-seropositive cats downregulated TLR7 and TNF-α expression between 4 and 24 hpi, and 4 and 12 hpi, respectively. IFN-β was upregulated early in FIPV-infected monocytes from FCoV-seropositive cats, with a significant difference observed at 12 hpi compared to FCoV-seronegative cats. The viral load in the CRFK and FIPV-infected monocytes in both cohorts of cats was similar over time. Conclusion TLR7 may be the key TLR involved in evading the innate response against inhibiting TNF-α production. Distinct TLR expression profiles between FCoV-seronegative and FCoV-seropositive cats were observed. The associated TLR that plays a role in the induction of IFN-β needs to be explored further.
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Affiliation(s)
| | - Gayathri Thevi Selvarajah
- Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Abdul Rahman Omar
- Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Farina Mustaffa-Kamal
- Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
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Lee Y, Maes RK, Kruger JM, Kiupel M, Giessler KS, Soboll Hussey G. Safety and Efficacy of Felid Herpesvirus-1 Deletion Mutants in Cats. Viruses 2021; 13:v13020163. [PMID: 33499363 PMCID: PMC7911815 DOI: 10.3390/v13020163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 01/10/2021] [Accepted: 01/18/2021] [Indexed: 02/05/2023] Open
Abstract
Felid herpesvirus-1 (FeHV-1) is an important respiratory and ocular pathogen of cats and current vaccines are limited in duration and efficacy because they do not prevent infection, viral nasal shedding and latency. To address these shortcomings, we have constructed FeHV-1 gE-TK- and FeHV-1 PK- deletion mutants (gE-TK- and PK-) using bacterial artificial chromosome (BAC) mutagenesis and shown safety and immunogenicity in vitro. Here, we compare the safety and efficacy of a prime boost FeHV-1 gE-TK- and FeHV-1 PK- vaccination regimen with commercial vaccination in cats. Cats in the vaccination groups were vaccinated at 3-week intervals and all cats were challenge infected 3 weeks after the last vaccination. Evaluations included clinical signs, nasal shedding, virus neutralizing antibodies (VN), cytokine mRNA gene expression, post-mortem histology and detection of latency establishment. Vaccination with gE-TK- and PK- mutants was safe and resulted in significantly reduced clinical disease scores, pathological changes, viral nasal shedding, and viral DNA in the trigeminal ganglia (the site of latency) following infection. Both mutants induced VN antibodies and interferons after immunization. In addition, after challenge infection, we observed a reduction of IL-1β expression, and modulation of TNFα, TGFβ and IL10 expression. In conclusion, this study shows the merits of using FeHV-1 deletion mutants for prevention of FeHV-1 infection in cats.
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Affiliation(s)
- Yao Lee
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA; (Y.L.); (R.K.M.); (M.K.); (K.S.G.)
| | - Roger K. Maes
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA; (Y.L.); (R.K.M.); (M.K.); (K.S.G.)
- Veterinary Diagnostic Laboratory, Michigan State University, 4125 Beaumont Road, Lansing, MI 48910, USA
| | - John M. Kruger
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA;
| | - Matti Kiupel
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA; (Y.L.); (R.K.M.); (M.K.); (K.S.G.)
- Veterinary Diagnostic Laboratory, Michigan State University, 4125 Beaumont Road, Lansing, MI 48910, USA
| | - Kim S. Giessler
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA; (Y.L.); (R.K.M.); (M.K.); (K.S.G.)
| | - Gisela Soboll Hussey
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48824, USA; (Y.L.); (R.K.M.); (M.K.); (K.S.G.)
- Correspondence: ; Tel.: +1-517-432-3273
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Uddin MJ, Kaewmala K, Neuhof C, Tesfaye D, Tholen E, Looft C, Cinar MU, Schellander K. Heterogeneous expression of Toll-like receptors genes in lymphoid tissues of different ages pigs. GENE REPORTS 2019. [DOI: 10.1016/j.genrep.2019.100401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Wheat W, Chow L, Coy J, Contreras E, Lappin M, Dow S. Activation of upper respiratory tract mucosal innate immune responses in cats by liposomal toll-like receptor ligand complexes delivered topically. J Vet Intern Med 2019; 33:838-845. [PMID: 30770582 PMCID: PMC6430862 DOI: 10.1111/jvim.15426] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 01/11/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Nonspecific induction of local innate immune responses by mucosally administered immunotherapy is a new approach to protection from upper respiratory tract infections. Therefore, a new liposome-toll-like receptor complex (LTC) immune stimulant was developed and investigated for its ability to activate innate immune responses in cats, both in vitro and in vivo, as part of an initial evaluation of LTC for use as an immunotherapeutic agent in cats. OBJECTIVES We hypothesized that LTC could activate innate immune responses in cats after topical application to nasal and oropharyngeal mucosal surfaces. ANIMALS Mucosal immune responses to topical administration of LTC were assessed in 7 healthy, purpose-bred cats, and in vitro responses were assessed using blood samples from healthy cats. METHODS Cytokine and cellular immune responses to LTC were evaluated in blood samples, nasal lavage specimens, and pharyngeal swabs from cats, using reverse transcriptase polymerase chain reaction assays, ELISA assays, and flow cytometry. RESULTS Liposome-TLR complexes rapidly activated leukocytes in vitro, including upregulation of costimulatory molecule expression and cytokine production. Topical administration of LTC in healthy cats triggered rapid recruitment of monocytes to the nasal and oropharyngeal mucosa. CONCLUSIONS AND CLINICAL IMPORTANCE Liposome-TLR complexes were found to effectively activate innate immune responses in cats after mucosal administration. These findings suggest that LTC have potential for use as a new mucosally administered immunotherapy for nonspecific protection from viral and bacterial respiratory tract infections.
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Affiliation(s)
- William Wheat
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Lyndah Chow
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Jonathan Coy
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Elena Contreras
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Michael Lappin
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Steven Dow
- Center for Immune and Regenerative Medicine and the Center for Companion Animal Studies, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
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Malbon AJ, Meli ML, Barker EN, Davidson AD, Tasker S, Kipar A. Inflammatory Mediators in the Mesenteric Lymph Nodes, Site of a Possible Intermediate Phase in the Immune Response to Feline Coronavirus and the Pathogenesis of Feline Infectious Peritonitis? J Comp Pathol 2018; 166:69-86. [PMID: 30691609 PMCID: PMC7094650 DOI: 10.1016/j.jcpa.2018.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/28/2018] [Accepted: 11/05/2018] [Indexed: 02/09/2023]
Abstract
Feline infectious peritonitis (FIP) is an almost invariably fatal feline coronavirus (FCoV)-induced disease thought to arise from a combination of viral mutations and an overexuberant immune response. Natural initial enteric FCoV infection may remain subclinical, or result in mild enteric signs or the development of FIP; cats may also carry the virus systemically with no adverse effect. This study screened mesenteric lymph nodes (MLNs), the presumed first site of FCoV spread from the intestine regardless of viraemia, for changes in the transcription of a panel of innate immune response mediators in response to systemic FCoV infection and with FIP, aiming to identify key pathways triggered by FCoV. Cats with and without FIP, the latter with and without FCoV infection in the MLN, were compared. Higher expression levels in FIP were found for toll-like receptors (TLRs) 2, 4 and 8. These are part of the first line of defence and suggest a response to both viral structural proteins and viral nucleic acid. Expression of genes encoding inflammatory cytokines and chemokines, including interleukin (IL)-1β, IL-6, IL-15, tumour necrosis factor (TNF)-α, CXCL10, CCL8, interferon (IFN)-α, IFN-β and IFN-γ, was higher in cats with FIP, consistent with inflammatory pathway activation. Expression of genes encoding transcription factors STAT1 and 2, regulating signalling pathways, particularly of the interferons, was also higher. Among cats without FIP, there were few differences between virus-positive and virus-negative MLNs; however, TLR9 and STAT2 expression were higher with infection, suggesting a direct viral effect. The study provides evidence for TLR involvement in the response to FCoV. This could open up new avenues for therapeutic approaches.
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Affiliation(s)
- A J Malbon
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Switzerland; Graduate School for Cellular and Biomedical Sciences, Bern, Switzerland; Center for Clinical Studies, Switzerland
| | - M L Meli
- Center for Clinical Studies, Switzerland; Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Switzerland
| | | | - A D Davidson
- School of Cellular and Molecular Medicine, Faculty of Life Sciences, University of Bristol, UK
| | | | - A Kipar
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Switzerland; Institute of Global Health, Faculty of Health and Life Sciences, University of Liverpool, UK.
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de Pablo-Maiso L, Doménech A, Echeverría I, Gómez-Arrebola C, de Andrés D, Rosati S, Gómez-Lucia E, Reina R. Prospects in Innate Immune Responses as Potential Control Strategies against Non-Primate Lentiviruses. Viruses 2018; 10:v10080435. [PMID: 30126090 PMCID: PMC6116218 DOI: 10.3390/v10080435] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/08/2018] [Accepted: 08/10/2018] [Indexed: 02/06/2023] Open
Abstract
Lentiviruses are infectious agents of a number of animal species, including sheep, goats, horses, monkeys, cows, and cats, in addition to humans. As in the human case, the host immune response fails to control the establishment of chronic persistent infection that finally leads to a specific disease development. Despite intensive research on the development of lentivirus vaccines, it is still not clear which immune responses can protect against infection. Viral mutations resulting in escape from T-cell or antibody-mediated responses are the basis of the immune failure to control the infection. The innate immune response provides the first line of defense against viral infections in an antigen-independent manner. Antiviral innate responses are conducted by dendritic cells, macrophages, and natural killer cells, often targeted by lentiviruses, and intrinsic antiviral mechanisms exerted by all cells. Intrinsic responses depend on the recognition of the viral pathogen-associated molecular patterns (PAMPs) by pathogen recognition receptors (PRRs), and the signaling cascades leading to an antiviral state by inducing the expression of antiviral proteins, including restriction factors. This review describes the latest advances on innate immunity related to the infection by animal lentiviruses, centered on small ruminant lentiviruses (SRLV), equine infectious anemia virus (EIAV), and feline (FIV) and bovine immunodeficiency viruses (BIV), specifically focusing on the antiviral role of the major restriction factors described thus far.
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MESH Headings
- Animals
- Cats
- Cattle
- Dendritic Cells/immunology
- Dendritic Cells/virology
- Gene Expression Regulation/immunology
- Goats
- Horses
- Immunity, Innate
- Immunodeficiency Virus, Bovine/immunology
- Immunodeficiency Virus, Bovine/pathogenicity
- Immunodeficiency Virus, Feline/immunology
- Immunodeficiency Virus, Feline/pathogenicity
- Infectious Anemia Virus, Equine/immunology
- Infectious Anemia Virus, Equine/pathogenicity
- Interferon Regulatory Factors/genetics
- Interferon Regulatory Factors/immunology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/virology
- Lentivirus Infections/genetics
- Lentivirus Infections/immunology
- Lentivirus Infections/virology
- Macrophages/immunology
- Macrophages/virology
- Pathogen-Associated Molecular Pattern Molecules/immunology
- Receptors, Pattern Recognition/genetics
- Receptors, Pattern Recognition/immunology
- Sheep
- T-Lymphocytes/immunology
- T-Lymphocytes/virology
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Affiliation(s)
- Lorena de Pablo-Maiso
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Ana Doménech
- Dpto. Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain.
| | - Irache Echeverría
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Carmen Gómez-Arrebola
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Damián de Andrés
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Sergio Rosati
- Malattie Infettive degli Animali Domestici, Dipartimento di Scienze Veterinarie, Università degli Studi di Torino, Torino 10095, Italy.
| | - Esperanza Gómez-Lucia
- Dpto. Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain.
| | - Ramsés Reina
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
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Loots AK, Cardoso-Vermaak E, Venter EH, Mitchell E, Kotzé A, Dalton DL. The role of toll-like receptor polymorphisms in susceptibility to canine distemper virus. Mamm Biol 2018. [DOI: 10.1016/j.mambio.2017.11.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Alan E, Liman N. Toll-like receptor expression patterns in the rat uterus during post partum involution. Reprod Fertil Dev 2017; 30:330-348. [PMID: 28701256 DOI: 10.1071/rd16431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 06/12/2017] [Indexed: 11/23/2022] Open
Abstract
Toll-like receptors (TLRs) belong to a family of pathogen recognition receptors and play critical roles in detecting and responding to invading pathogens. TLR expression could be significant because, in the uterus, the reproductive tract is an important site of exposure to and infection by pathogens during the post partum involution period. To clarify the expression and localisation patterns of TLRs in the rat uterus on Days 1, 3, 5 and 10 post partum (PP1, PP3, PP5 and PP10 respectively), immunohistochemistry and western blotting were used to analyse TLR1-7, TLR9 and TLR10. The immunohistochemistry results indicated that TLR1-7, TLR9 and TLR10 were localised in both the cytoplasm and nuclei of luminal and glandular epithelium, stromal fibroblasts and myometrial cells in the rat uterus. In the luminal epithelium, TLR4-7 were also found in lateral membranes, whereas TLR10 was present in apical membranes. Western blot analysis revealed that the expression of TLR proteins increased with the number of days post partum, reaching a maximum on PP10, although levels did not differ significantly from those on PP1 (P>0.05). These findings confirm that TLR1-7, TLR9 and TLR10 are constitutively expressed in uterine cells and that localisation pattern of TLRs in the endometrium varies with structural changes in the uterus on different days of involution. These results suggest that TLRs may play a role in uterine repair and remodelling during physiological involution.
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Affiliation(s)
- Emel Alan
- Department of Histology and Embryology, Faculty of Veterinary Medicine, Erciyes University, Kayseri 38039, Turkey
| | - Narin Liman
- Department of Histology and Embryology, Faculty of Veterinary Medicine, Erciyes University, Kayseri 38039, Turkey
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Jursza-Piotrowska E, Siemieniuch MJ. Comparison of the effect of lipopolysaccharide on tumor necrosis factor α (TNF-α) secretion and TNF and TNFR1 mRNA levels in feline endometrium throughout the estrous cycle during pyometra and after medroxyprogesterone acetate treatment. J Reprod Dev 2016; 62:385-91. [PMID: 27097764 PMCID: PMC5004795 DOI: 10.1262/jrd.2016-002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Endotoxins released by Gram-negative bacteria are potent stimulators of tumor
necrosis factor α (TNF-α) production. The objectives of this study were to evaluate
plasma levels of TNF-α, TNF-α secretion, and mRNA levels of TNF and
TNF-α receptor type 1 (TNFR1) following exposure to
lipopolysaccharide (LPS). For this, we used cultured endometrial cells or organ
cultures, throughout the estrous cycle, after hormone treatment with
medroxyprogesterone acetate (MPA), and during pyometra. Plasma TNF-α concentrations
were increased in animals at estrus (P < 0.05) compared to other groups. In the
LPS-challenged endometrium, secretion of TNF-α by tissues collected during estrus
increased (P < 0.001) compared to that of other groups. LPS, alone or combined
with TNF-α, upregulated TNF gene expression in the feline
endometrium at diestrus (P < 0.001 for both treatments), in queens treated
short-term with MPA (P < 0.01 and P < 0.05, respectively) and in queens treated
long-term with MPA (P < 0.01 and P < 0.001, respectively). During pyometra,
TNF and TNFR1 mRNA were increased only after
tissues were challenged with TNF-α and LPS (P < 0.001 and P < 0.01,
respectively). When cultured endometrial cells were challenged with LPS, the
concentration of TNF-α increased only in epithelial cells after 4 h and 12 h (P <
0.05 and P < 0.01, respectively). Since LPS did not affect stromal cells, but
TNF-α increased its own transcript after 2 h (P < 0.01), 4 h (P < 0.05) and 12
h (P < 0.001), we assume that stromal cells are not directly involved in pathogen
recognition, as was the case for epithelial cells.
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Affiliation(s)
- Ewelina Jursza-Piotrowska
- Department of Reproductive Immunology and Pathology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, 10-748 Olsztyn, Poland
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Cambier LC, Heinen MPAL, Bagut ET, Antoine NA, Mignon BR. Overexpression of TLR-2 and TLR-4 mRNA in feline polymorphonuclear neutrophils exposed to Microsporum canis. Vet Dermatol 2016; 27:78-81e22. [PMID: 26914839 DOI: 10.1111/vde.12295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Polymorphonuclear neutrophils (PMNs), along with macrophages, are the first leukocytes recruited to the site of infection in dermatophytoses and are responsible for the in fine elimination of the fungus. It has been demonstrated that feline PMNs produce pro-inflammatory cytokines after stimulation with Microsporum canis. The activation of these cells results from the recognition of specific PAMPs (pathogen associated molecular patterns) from M. canis by PRRs (pattern recognition receptors) of PMNs. The C-type lectin receptors (CLRs) and toll-like receptors (TLRs) are the two main PRRs in phagocytic cells that recognize fungal components. HYPOTHESIS/OBJECTIVE The aim of this study was to evaluate the expression of TLR-2, TLR-4 and dectin-1 mRNA in feline PMNs exposed to different components from M. canis. METHODS Feline PMNs were stimulated for 2 h or 4 h with either live arthroconidia, heat-killed arthroconidia or secreted components from M. canis. The levels of TLR-2, TLR-4 and dectin-1 mRNA were assessed by RT-qPCR. RESULTS Results showed an increase of TLR-2 and TLR-4 mRNA levels in feline PMNs stimulated with live and heat-killed arthroconidia, but not in those stimulated with the secreted components from M. canis. No significant variation in dectin-1 mRNA expression was observed in PMNs stimulated with the different fungal components. CONCLUSIONS AND CLINICAL IMPORTANCE The overexpression of TLR-2 and TLR-4 mRNAs in stimulated feline PMNs suggests that these receptors are involved in the host immune response through the recognition of M. canis PAMPs.
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Affiliation(s)
- Ludivine C Cambier
- Veterinary Mycology, FARAH (Fundamental and Applied Research for Animals & Health), Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20 B-43a, Liège, 4000, Belgium
| | - Marie-Pierre A-L Heinen
- Veterinary Mycology, FARAH (Fundamental and Applied Research for Animals & Health), Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20 B-43a, Liège, 4000, Belgium
| | - Elena T Bagut
- Veterinary Mycology, FARAH (Fundamental and Applied Research for Animals & Health), Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20 B-43a, Liège, 4000, Belgium.,Parasitology and Parasitic Diseases Unit, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street, Cluj-Napoca, 400372, Romania
| | - Nadine A Antoine
- Animal Histology, FARAH, Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20 B-43a, Liège, 4000, Belgium
| | - Bernard R Mignon
- Veterinary Mycology, FARAH (Fundamental and Applied Research for Animals & Health), Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20 B-43a, Liège, 4000, Belgium
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12
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Nelli RK, Maes R, Kiupel M, Hussey GS. Use of a feline respiratory epithelial cell culture system grown at the air-liquid interface to characterize the innate immune response following feline herpesvirus 1 infection. Virus Res 2016; 214:39-48. [PMID: 26795546 DOI: 10.1016/j.virusres.2016.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/11/2016] [Accepted: 01/13/2016] [Indexed: 12/24/2022]
Abstract
Infection with feline herpesvirus-1 (FHV-1) accounts for 50% of viral upper respiratory diseases in domestic cats and is a significant cause of ocular diseases. Despite the clinical significance and high prevalence of FHV-1 infection, currently available vaccines cannot completely protect cats from infection and lifelong latency. FHV-1 infects via the mucous membranes and replicates in respiratory epithelial cells, but very little is known about the early innate immunity at this site. To address questions about immunity to FHV-1, feline respiratory epithelial cells cultured at air-liquid interface (ALI-FRECs) were established by collecting respiratory tracts from 6 healthy cats after euthanasia. Cells were isolated, cultured and characterized histologically and immunologically before infection with FHV-1. The expression of Toll-like receptors (TLRs), cytokine and chemokine responses were measured by real time PCR. ALI-FRECs morphologically resembled the natural airways of cats with multilayered columnar epithelial cells and cilia. Immunological properties of the natural airways were maintained in ALI-FRECs, as evidenced by the expression of TLRs, cytokines, chemokines, interferons, beta-defensins, and other regulatory genes. Furthermore, ALI-FRECs were able to support infection and replication of FHV-1, as well as modulate transcriptional regulation of various immune genes in response to infection. IL-1β and TNFα were increased in ALI-FRECs by 24hpi, whereas expression levels of IFN-α and TLR9 were not increased until 36hpi. In contrast, TLR3, GM-CSF and TGF-1β expression was down-regulated at 36hpi. The data presented show the development of a system ideal for investigating the molecular pathogenesis and immunity of FHV-1 or other respiratory pathogens.
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Affiliation(s)
- Rahul K Nelli
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, 784 Wilson Road, East Lansing, MI 48824, USA.
| | - Roger Maes
- Diagnostic Center for Population and Animal Health, 4125 Beaumont Road, Building 0215, Lansing, MI 48910, USA.
| | - Matti Kiupel
- Diagnostic Center for Population and Animal Health, 4125 Beaumont Road, Building 0215, Lansing, MI 48910, USA.
| | - Gisela Soboll Hussey
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, 784 Wilson Road, East Lansing, MI 48824, USA.
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Cheng C, Sun WK, Liu R, Wang RM, Chen YH, Wang Y, Li JL, Lu XB, Gao R. Comparison of gene expression of Toll-like receptors and antimicrobial peptides in immune organs and tissues between Yorkshire and Tibetan pigs. Anim Genet 2015; 46:272-9. [PMID: 25917299 DOI: 10.1111/age.12286] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2015] [Indexed: 11/29/2022]
Abstract
Toll-like receptors (TLRs), an important family of pattern-recognition receptors, and antimicrobial peptides (AMPs) contribute to the first line of innate protection of mammals against microbes. To compare characteristics of innate immunity between Tibetan and Yorkshire pigs, we investigated the mRNA abundance of TLR genes (TLR1-TLR9) and two AMP-encoding genes (PBD-1 and PR-39) in thymus, spleen, blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes of the two breeds at ages of 6, 12 and 24 weeks using quantitative real-time PCR. Results showed that all mRNAs were detected in all tissues. Transcript levels of the major TLR genes of Tibetan pigs were significantly higher than those of Yorkshires in most tissues of the immune system, with a higher abundance of porcine (PBD-1) (beta-defensin-1) and PR-39 mRNA in lymphoid organs and tissues, especially blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes. Our data suggest that Tibetan pigs have stronger innate immunity for triggering local and/or systemic immune responses to eliminate infections with pathogenic microorganisms.
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Affiliation(s)
- C Cheng
- Key Laboratory for Bio-resource and Eco-environment of the Education Ministry, College of Life Science, Sichuan University, Chengdu, Sichuan, 610064, China; Key Laboratory for Animal Disease Prevention and Food Safety of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan, 610064, China; College of Bioengineering, Sichuan University of Science & Engineering, Zigong, Sichuan, 643000, China
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The role of toll-like receptors 2 and 4 in the pathogenesis of feline pyometra. Theriogenology 2015; 83:596-603. [DOI: 10.1016/j.theriogenology.2014.10.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 10/17/2014] [Accepted: 10/27/2014] [Indexed: 11/21/2022]
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Targeting TLR2 for vaccine development. J Immunol Res 2014; 2014:619410. [PMID: 25057505 PMCID: PMC4098989 DOI: 10.1155/2014/619410] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/16/2014] [Accepted: 06/04/2014] [Indexed: 02/07/2023] Open
Abstract
Novel and more effective immunization strategies against many animal diseases may profit from the current knowledge on the modulation of specific immunity through stimulation of innate immune receptors. Toll-like receptor (TLR)2-targeting formulations, such as synthetic lipopeptides and antigens expressed in fusion with lipoproteins, have been shown to have built-in adjuvant properties and to be effective at inducing cellular and humoral immune mechanisms in different animal species. However, contradictory data has arisen concerning the profile of the immune response elicited. The benefits of targeting TLR2 for vaccine development are thus still debatable and more studies are needed to rationally explore its characteristics. Here, we resume the main features of TLR2 and TLR2-induced immune responses, focusing on what has been reported for veterinary animals.
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Flies AS, Maksimoski MT, Mansfield LS, Weldele ML, Holekamp KE. Characterization of Toll-like receptors 1-10 in spotted hyenas. Vet Res Commun 2014; 38:165-70. [PMID: 24488231 DOI: 10.1007/s11259-014-9592-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2014] [Indexed: 11/27/2022]
Abstract
Previous research has shown that spotted hyenas (Crocuta crocuta) regularly survive exposure to deadly pathogens such as rabies, canine distemper virus, and anthrax, suggesting that they have robust immune defenses. Toll-like receptors (TLRs) recognize conserved molecular patterns and initiate a wide range of innate and adaptive immune responses. TLR genes are evolutionarily conserved, and assessing TLR expression in various tissues can provide insight into overall immunological organization and function. Studies of the hyena immune system have been minimal thus far due to the logistical and ethical challenges of sampling and preserving the immunological tissues of this and other long-lived, wild species. Tissue samples were opportunistically collected from captive hyenas humanely euthanized for a separate study. We developed primers to amplify partial sequences for TLRs 1-10, sequenced the amplicons, compared sequence identity to those in other mammals, and quantified TLR expression in lymph nodes, spleens, lungs, and pancreases. Results show that hyena TLR DNA and protein sequences are similar to TLRs in other mammals, and that TLRs 1-10 were expressed in all tissues tested. This information will be useful in the development of new assays to understand the interactions among the hyena immune system, pathogens, and the microbial communities that inhabit hyenas.
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Affiliation(s)
- Andrew S Flies
- Department of Zoology, Michigan State University, East Lansing, MI, 48824-1317, USA,
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Expression patterns of porcine Toll-like receptors family set of genes (TLR1-10) in gut-associated lymphoid tissues alter with age. Res Vet Sci 2013; 95:92-102. [PMID: 23433683 DOI: 10.1016/j.rvsc.2013.01.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 01/17/2013] [Accepted: 01/25/2013] [Indexed: 01/09/2023]
Abstract
The aim was to study the expression pattern of the porcine TLR family (TLR1-10) genes in gut-associated lymphoid tissues (GALT) of varying ages. A total of nine clinically healthy pigs of three ages group (1 day, 2 months and 5 months old) were selected for this experiment (three pigs in each group). Tissues from intestinal mucosa in stomach, duodenum, jejunum and ileum and mesenteric lymph node (MLN) were used. mRNA expression of TLRs (1-10) was detectable in all tissues and TLR3 showed the highest mRNA abundance among TLRs. TLR3 expression in stomach, and TLR1 and TLR6 expression in MLN were higher in adult than newborn pigs. The western blot results of TLR2, 3 and 9 in some cases, did not coincide with the mRNA expression results. The protein localization of TLR2, 3 and 9 showed that TLR expressing cells were abundant in the lamina propria, Peyer's patches in intestine, and around and within the lymphoid follicles in the MLN. This expressions study sheds the first light on the expression patterns of all TLR genes in GALT at different ages of pigs.
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Dolieslager SMJ, Lappin DF, Bennett D, Graham L, Johnston N, Riggio MP. The influence of oral bacteria on tissue levels of Toll-like receptor and cytokine mRNAs in feline chronic gingivostomatitis and oral health. Vet Immunol Immunopathol 2012; 151:263-74. [PMID: 23287555 DOI: 10.1016/j.vetimm.2012.11.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 11/16/2012] [Accepted: 11/28/2012] [Indexed: 01/09/2023]
Abstract
Feline chronic gingivostomatitis (FCGS) is an inflammatory disease of the oral cavity that causes severe pain and distress in affected cats. Treatment methods are currently very limited. The aims of this study were to assess the feline innate immune response by investigating the levels of cytokine and Toll-like receptor (TLR) mRNAs in tissue biopsies of cats with and without FCGS, and to relate this to the presence or absence of putative oral pathogens identified previously within these cats. Mucosal biopsies were collected from 28 cats with FCGS and eight healthy cats. The levels of TLR (TLR2, TLR3, TLR4, TLR7, TLR9) and cytokine (IL-1β, IL-4, IL-6, IL-10, IL-12, TNF-α, IFN-γ) mRNA was determined using quantitative PCR. In the FCGS group a statistically significant increase was seen in TLR2, TLR7, TNF-α, IFN-γ, IL-1β and IL-6 mRNA levels compared to the healthy group. In cats where Tannerella forsythia was present, statistically significant increases were seen in TLR2, TLR4, TLR7, TLR9, TNF-α and IL-1β mRNA levels compared to cats where this putative pathogen was absent. Statistically significant increases in mRNA expression were also seen in cats harbouring feline calicivirus (FCV) (TLR2, IL-1β, IL-6, IFN-γ) and Porphyromonas circumdentaria (TLR2, TLR3) compared to cats where these putative pathogens were absent. Pasteurella multocida subsp. multocida and Pseudomonas sp. did not significantly alter the expression of any TLR or cytokine mRNAs when compared to animals who tested negative for these species, while cats colonised with P. multocida subsp. septica demonstrated a statistically significant reduction in the expression of TLR7, TNF-α and IFN-γ mRNAs compared to cats free of this species. The expression of mRNA for several TLRs and cytokines is elevated in FCGS. A positive correlation was observed between clinical disease severity and the presence of FCV (p=0.001; Rho=0.58). Although the number of cats harbouring T. forsythia was low by comparison, 80% of samples in which it was present were from cases with the highest clinical disease severity. Positive correlations with clinical disease severity were seen for TLR2 (p=0.00086), TLR7 (p=0.049), TNF-α (p=0.027), IFN-γ (p=0.0015), IL-1β (p=0.004) and IL-6 (p=0.00001) mRNAs. The putative pathogens FCV and T. forsythia may be important in stimulating a host immune response to FCGS and may play a role in the pathogenesis of this disease.
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Affiliation(s)
- Sanne Maria Johanna Dolieslager
- Infection & Immunity Research Group, Dental School, University of Glasgow, Glasgow Dental Hospital & School, 378 Sauchiehall Street, Glasgow G2 3JZ, United Kingdom
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Uddin MJ, Nuro-Gyina PK, Islam MA, Tesfaye D, Tholen E, Looft C, Schellander K, Cinar MU. Expression dynamics of Toll-like receptors mRNA and cytokines in porcine peripheral blood mononuclear cells stimulated by bacterial lipopolysaccharide. Vet Immunol Immunopathol 2012; 147:211-22. [PMID: 22578850 PMCID: PMC11141511 DOI: 10.1016/j.vetimm.2012.04.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 04/07/2012] [Accepted: 04/20/2012] [Indexed: 01/25/2023]
Abstract
The Toll-like receptor (TLR)4 is critical for the recognition of Gram-negative bacterial lipopolysaccharide (LPS) but in porcine peripheral blood mononuclear cells (PBMCs) it may cooperate with other TLRs and lead to the production of inflammatory cytokines. Therefore, we analyzed TLR1-10 mRNA expression in porcine PBMCs stimulated with LPS over time (1-48 h) by using quantitative real-time PCR and cytokine proteins level by ELISA in culture supernatant. TLR1-10 mRNA was detectable in porcine PBMCs. When compared with the control (non-stimulated), TLR1 mRNA were increased (p<0.05) at 3 h after challenge with 1 μg/ml LPS, whereas TLR1 and TLR2 mRNA were increased (p<0.01) at 6 h after challenge with 10 μg/ml LPS. TLR4 increased (p<0.001) at 3h after challenge with LPS and remained constant. TLR5 and TLR6 mRNA increased (p<0.05) at 9 h and 1 h after of LPS stimulation, respectively. The mRNA of CD14 and MD2 were increased (p<0.001) at 1h after LPS stimulation. Additionally, at most of the time analyzed, the mRNA expression increased with the dose of LPS. The LPS concentration had influence (p<0.05) on all the TLRs expression except TLR10; whereas time had effect (p<0.05) on all TLRs expression except TLR2, 3, 6 and 10. When compared to the control, the cytokines IL1b, IL8 and TNFα proteins were increased (p<0.001) immediately at 1 h after LPS stimulation and remained constant till 48 h. IL12b was increased (p<0.001) 12 h after challenge with 10 μg/ml of LPS. Although IL8 level was the highest, the higher (p<0.05) expression of all these inflammatory cytokines indicate that upon interacting with TLRs, LPS exerted inflammatory response in PBMCs through the production of Th1 type cytokines. The production of cytokines was influenced (p<0.001) by both the dose of LPS and the stimulation time. Hence, the porcine PBMCs are likely able to express all members of TLRs.
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Affiliation(s)
- Muhammad Jasim Uddin
- Institute of Animal Science, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany.
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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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Salem ML. Triggering of toll-like receptor signaling pathways in T cells contributes to the anti-tumor efficacy of T cell responses. Immunol Lett 2011; 137:9-14. [PMID: 21352854 DOI: 10.1016/j.imlet.2011.02.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 02/15/2011] [Accepted: 02/16/2011] [Indexed: 02/07/2023]
Abstract
Traditionally, expression of toll-like receptors (TLRs) has been associated with innate immune cells in particular professional antigen presenting cells and natural killer cells. This led to the concept that the adjuvant effects of ligation of TLR in a host occur mainly in innate immune cells. However, this concept has been challenged by recent studies including ours demonstrating that T cells express appreciated levels of different TLRs, which can serve as costimulatory co-receptors during polyclonal and antigen-specific stimulation of T cells. Because T cells express low levels of TLRs as compared to innate immune cells, increasing the expression levels of TLRs in T cells can significantly maximize their responses to the costimulatory effects of TLR ligation. This review article focuses on the potential role of TLR expression in T cells in their responses to vaccination regimen containing TLR agonists and how it can be modulated to optimize anti-tumor immunity.
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Affiliation(s)
- Mohamed Labib Salem
- Immunology and Biotechnology Unit, Department of Zoology, Tanta University, Egypt.
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Robert-Tissot C, Rüegger VL, Cattori V, Meli ML, Riond B, Gomes-Keller MA, Vögtlin A, Wittig B, Juhls C, Hofmann-Lehmann R, Lutz H. The innate antiviral immune system of the cat: molecular tools for the measurement of its state of activation. Vet Immunol Immunopathol 2011; 143:269-81. [PMID: 21719112 PMCID: PMC7112645 DOI: 10.1016/j.vetimm.2011.06.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The innate immune system plays a central role in host defence against viruses. While many studies portray mechanisms in early antiviral immune responses of humans and mice, much remains to be discovered about these mechanisms in the cat. With the objective of shedding light on early host-virus interactions in felids, we have developed 12 real-time TaqMan(®) qPCR systems for feline genes relevant to innate responses to viral infection, including those encoding for various IFNα and IFNω subtypes, IFNβ, intracellular antiviral factor Mx, NK cell stimulator IL-15 and effectors perforin and granzyme B, as well as Toll-like receptors (TLRs) 3 and 8. Using these newly developed assays and others previously described, we measured the relative expression of selected markers at early time points after viral infection in vitro and in vivo. Feline embryonic fibroblasts (FEA) inoculated with feline leukemia virus (FeLV) indicated peak levels of IFNα, IFNβ and Mx expression already 6h after infection. In contrast, Crandell-Rees feline kidney (CrFK) cells inoculated with feline herpes virus (FHV) responded to infection with high levels of IFNα and IFNβ only after 24h, and no induction of Mx could be detected. In feline PBMCs challenged in vitro with feline immunodeficiency virus (FIV), maximal expression levels of IFNα, β and ω subtype genes as well as IL-15 and TLRs 3, 7 and 8 were measured between 12 and 24h after infection, whereas expression levels of proinflammatory cytokine gene IL-6 were consistently downregulated until 48h post inoculation. A marginal upregulation of granzyme B was also observed within 3h after infection. In an in vivo experiment, cats challenged with FIV exhibited a 2.4-fold increase in IFNα expression in blood 1 week post infection. We furthermore demonstrate the possibility of stimulating feline immune cells in vitro with various immune response modifiers (IRMs) already known for their immunostimulatory properties in mice and humans, namely Poly IC, Resiquimod (R-848) and dSLIM™, a synthetic oligonucleotide containing several unmethylated CpG motifs. Stimulation of feline PBMCs with dSLIM™ and R-848 effectively enhanced expression of IFNα within 12h by factors of 6 and 12, respectively, and Poly IC induced an increase in Mx mRNA expression of 28-fold. Altogether, we describe new molecular tools and their successful use for the characterization of innate immune responses against viruses in the cat and provide evidence that feline cells can be stimulated by synthetic molecules to enhance their antiviral defence mechanisms.
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Affiliation(s)
- Céline Robert-Tissot
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 260, CH-8057 Zurich, Switzerland.
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Kannaki T, Shanmugam M, Verma P. Toll-like receptors and their role in animal reproduction. Anim Reprod Sci 2011; 125:1-12. [DOI: 10.1016/j.anireprosci.2011.03.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 02/21/2011] [Accepted: 03/14/2011] [Indexed: 01/08/2023]
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Toll-like receptors in domestic animals. Cell Tissue Res 2010; 343:107-20. [DOI: 10.1007/s00441-010-1047-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 09/01/2010] [Indexed: 12/13/2022]
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Franchini M, Zini E, Osto M, Jablonski K, Kaufmann K, Lutz TA, Reusch CE, Ackermann M. Feline pancreatic islet-like clusters and insulin producing cells express functional Toll-like receptors (TLRs). Vet Immunol Immunopathol 2010; 138:70-8. [PMID: 20674989 DOI: 10.1016/j.vetimm.2010.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 06/16/2010] [Accepted: 07/01/2010] [Indexed: 10/19/2022]
Abstract
Toll-like receptors (TLRs) are cellular receptors that recognize molecules derived from pathogens, endogenous molecules generated after cellular stress, and free fatty acids. TLR activation leads to a proinflammatory reaction that is fundamental in the initiation of an innate immune response and subsequent adaptive responses but also can damage tissues. TLRs are not only expressed within the immune system, but also in most other organ systems including the pancreas. TLR4 is expressed in pancreatic β-cells of rodents and humans and its stimulation affects insulin secretion in response to glucose. A low-grade inflammation is often associated with disturbed performance of β-cells and insulin resistance, the cardinal metabolic event of type-2 diabetes. Feline diabetes mellitus shares many similarities with type-2 diabetes in humans. Our objective was to elucidate the role of TLRs in feline pancreatic islets and islet-like clusters (ILC) that consist of islets with their adjacent tissue. We tested whether TLRs are triggered by their agonists and lead to the expression of inflammatory cytokines. We confirmed the expression of all known feline TLRs in pancreas and ILC. Furthermore, stimulation with TLR agonists increased IL-6 mRNA and protein content and the expression of other proinflammatory cytokines indicating a clear proinflammatory response. The reactivity to TLR ligands was stronger in β-cell enriched populations obtained after sorting by FACS indicating that inflammatory stimuli can also be generated within β-cells. We conclude that the microenvironment of feline β-cells harbor the potential for inflammatory reactions, that can be initiated by molecules released from bacteria or viruses or other molecules recognized by TLRs. Therefore infections associated with bacteriemia and viremia can induce inflammation in islets and damage the endocrine pancreatic tissue.
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Affiliation(s)
- Marco Franchini
- Institute of Virology, Vetsuisse Faculty, University of Zürich, Winterthurerstrasse 266a, 8057 Zürich, Switzerland.
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Howard KE, Reckling SK, Egan EA, Dean GA. Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats. Retrovirology 2010; 7:2. [PMID: 20085648 PMCID: PMC2835650 DOI: 10.1186/1742-4690-7-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 01/19/2010] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The mucosal pathogenesis of HIV has been shown to be an important feature of infection and disease progression. HIV-1 infection causes depletion of intestinal lamina propria CD4+ T cells (LPL), therefore, intestinal CD4+ T cell preservation may be a useful correlate of protection in evaluating vaccine candidates. Vaccine studies employing the cat/FIV and macaque/SIV models frequently use high doses of parenterally administered challenge virus to ensure high plasma viremia in control animals. However, it is unclear if loss of mucosal T cells would occur regardless of initial viral inoculum dose. The objective of this study was to determine the acute effect of viral dose on mucosal leukocytes and associated innate and adaptive immune responses. RESULTS Cats were vaginally inoculated with a high, middle or low dose of cell-associated and cell-free FIV. PBMC, serum and plasma were assessed every two weeks with tissues assessed eight weeks following infection. We found that irrespective of mucosally administered viral dose, FIV infection was induced in all cats. However, viremia was present in only half of the cats, and viral dose was unrelated to the development of viremia. Importantly, regardless of viral dose, all cats experienced significant losses of intestinal CD4+ LPL and CD8+ intraepithelial lymphocytes (IEL). Innate immune responses by CD56+CD3- NK cells correlated with aviremia and apparent occult infection but did not protect mucosal T cells. CD4+ and CD8+ T cells in viremic cats were more likely to produce cytokines in response to Gag stimulation, whereas aviremic cats T cells tended to produce cytokines in response to Env stimulation. However, while cell-mediated immune responses in aviremic cats may have helped reduce viral replication, they could not be correlated to the levels of viremia. Robust production of anti-FIV antibodies was positively correlated with the magnitude of viremia. CONCLUSIONS Our results indicate that mucosal immune pathogenesis could be used as a rapid indicator of vaccine success or failure when combined with a physiologically relevant low dose mucosal challenge. We also show that innate immune responses may play an important role in controlling viral replication following acute mucosal infection, which has not been previously identified.
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Affiliation(s)
- Kristina E Howard
- Center for Comparative Medicine and Translational Research, Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, USA
| | - Stacie K Reckling
- Center for Comparative Medicine and Translational Research, Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, USA
| | - Erin A Egan
- Center for Comparative Medicine and Translational Research, Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, USA
- Current address: Immunobio, 920 Main Campus Drive, Suite 405, Raleigh, NC, 27606, USA
| | - Gregg A Dean
- Center for Comparative Medicine and Translational Research, Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, USA
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Salem ML, Diaz-Montero CM, EL-Naggar SA, Chen Y, Moussa O, Cole DJ. The TLR3 agonist poly(I:C) targets CD8+ T cells and augments their antigen-specific responses upon their adoptive transfer into naïve recipient mice. Vaccine 2009; 27:549-57. [PMID: 19027047 PMCID: PMC3072892 DOI: 10.1016/j.vaccine.2008.11.013] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 10/31/2008] [Accepted: 11/03/2008] [Indexed: 02/07/2023]
Abstract
We have recently reported that the toll-like receptor 3 (TLR3) agonist poly(I:C) induces adjuvant effects to post vaccination CD8+ T cells responses through rapid induction of innate mediators, including NK cells, macrophages, dendritic cells (DCs), and inflammatory cytokines. However, whether this TLR3 agonist directly targets CD8+ T cells needs to be carefully investigated. In this study, we found that optimal post vaccination CD8+ T cell responses to ex vivo DC-based vaccination requires triggering of TLR3 signaling pathway in DCs in vitro as well as in the recipient host, indicating a role for other cell types. Real-time PCR analysis revealed that TLRs (TLR1-TLR13) are expressed in purified (>99% pure) CD4+ and CD8+ T cells from C57BL/6 and BALB/c mice, where the magnitude of the expression was strain and cell type dependent. In vitro, treatment of these purified T cells with poly(I:C) modulated the expression of TLRs including TLR3. Furthermore, non-specific and antigen-specific stimulation of CD8+ T cells by phorbol myristate acetate and MHC class I peptide-pulsed splenocytes, respectively, modulated TLR expression in purified CD4+ and CD8+ T cells. Importantly, brief conditioning of purified naïve TCR transgenic OT-1 (CD8+) T cells in vitro with poly(I:C) induced activation of these cells in absence of antigen stimulation. Interestingly, when these in vitro poly(I:C)-conditioned OT-1 cells were adoptively transferred into naïve recipient followed by peptide vaccination, they showed superior expansion and activation to their naïve counterparts. These results suggest that CD8+ T cells can be activated by triggering their TLR3. Furthermore, the data support the notion of direct involvement of TLRs in adaptive immune responses.
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Affiliation(s)
- Mohamed L. Salem
- Department of Surgery, Medical University of South Carolina, Charleston, SC 29425, USA
- Department of Zoology, Faculty of Science, Tanta University, Tanta, Egypt
- Corresponding author at: Department of Surgery, Section of Surgical Oncology, Medical University of South Carolina, Charleston, SC 29425, United States. Tel.: +1 843 792 7576; fax: +1 843 792 3200. , (M.L. Salem)
| | | | - Sabry A. EL-Naggar
- Department of Surgery, Medical University of South Carolina, Charleston, SC 29425, USA
- Department of Zoology, Faculty of Science, Tanta University, Tanta, Egypt
| | - Yian Chen
- Department of Surgery, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Omar Moussa
- Department of Pathology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - David J. Cole
- Department of Surgery, Medical University of South Carolina, Charleston, SC 29425, USA
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Lehman TL, O'Halloran KP, Fallon SA, Habermann LM, Campbell JA, Nordone S, Dean GA, Hoover EA, Avery PR. Altered bone marrow dendritic cell cytokine production to toll-like receptor and CD40 ligation during chronic feline immunodeficiency virus infection. Immunology 2008; 126:405-12. [PMID: 18775027 DOI: 10.1111/j.1365-2567.2008.02907.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Impaired dendritic cell (DC) function is thought to be central to human immunodeficiency virus-associated immunodeficiency. In this study, we examined the effect of chronic feline immunodeficiency virus (FIV) infection on DC cytokine production in response to microbial and T-cell stimulation. Cytokine production after either Toll-like receptor (TLR) or CD40 ligation in bone marrow-derived DCs (BM-DCs) was measured in naïve and chronically FIV-infected cats. The BM-DCs were stimulated with ligands to TLR-2, -3, -4, -7 and -9 or cocultured with 3T3 cells expressing feline CD40 ligand. Ligation of TLR-4 and TLR-9 in BM-DCs from infected cats resulted in a significant decrease in the ratio of interleukin-12 (IL-12) to IL-10. Conversely, TLR-7 ligation produced a significant increase in the IL-12 : IL-10 ratio in BM-DCs from infected cats. No difference was noted for TLR-3 ligation. RNA expression levels of TLR-2, -3, -4, -7 and -9 were not significantly altered by FIV infection. CD40 ligation significantly elevated both IL-10 and IL-12 messenger RNA production but did not alter the IL-12 : IL-10 ratio. Chronic FIV infection alters the ratio of immunoregulatory cytokines produced by BM-DCs in response to certain pathogen-derived signals, which is probably relevant to the increased risk of opportunistic infections seen in lentiviral infection.
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Affiliation(s)
- Tracy L Lehman
- Departments of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, 80523, USA
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Zhang YW, Davis EG, Blecha F, Wilkerson MJ. Molecular cloning and characterization of equine Toll-like receptor 9. Vet Immunol Immunopathol 2008; 124:209-19. [DOI: 10.1016/j.vetimm.2008.03.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Revised: 03/13/2008] [Accepted: 03/14/2008] [Indexed: 11/17/2022]
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Im Hof M, Williamson L, Summerfield A, Balmer V, Dutoit V, Kandimalla ER, Yu D, Zurbriggen A, Doherr MG, Peel J, Roosje PJ. Effect of synthetic agonists of toll-like receptor 9 on canine lymphocyte proliferation and cytokine production in vitro. Vet Immunol Immunopathol 2008; 124:120-31. [PMID: 18452997 DOI: 10.1016/j.vetimm.2008.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2007] [Revised: 02/19/2008] [Accepted: 03/04/2008] [Indexed: 01/10/2023]
Abstract
Synthetic agonists of TLR9 containing novel DNA structures and R'pG (wherein R=1-(2'-deoxy-beta-d-ribofuranosyl)-2-oxo-7-deaza-8-methyl-purine) motifs, referred to as immune modulatory oligonucleotides (IMOs), have been shown to stimulate T(H)-1-type-immune responses and potently reverse allergen-induced T(H)-2 responses to T(H)-1 responses in vitro and in vivo in mice. In order to investigate the immunomodulatory potential of IMOs in dogs, canine peripheral blood mononuclear cells (PBMC) from healthy dogs were stimulated with three different IMOs and a control IMO, alone or in combination with concanavalin A (ConA). Lipopolysaccharide (LPS) was used as a positive control for B lymphocyte activation. Carboxyfluorescein diacetate succinimidyl ester and phenotype staining was used to tag proliferating T and B lymphocytes (CD5(+) and CD21(+)) by flow cytometry. Real-time PCR and ELISA were processed to assay cytokine production of IFN-gamma, IL-10, TGF-beta, IL-6 and IL-10. Like LPS, IMOs alone induced neither proliferation of CD5(+) T cells nor CD21(+) B cells, but both LPS and IMO had the capacity to co-stimulate ConA and induced proliferation of B cells. In combination with ConA, one of the IMOs (IMO1) also induced proliferation of T cells. IMO1 also significantly enhanced the expression of IFN-gamma on the mRNA and protein level in canine PBMC, whereas expression of IL-10, TGF-beta and IL-4 mRNAs was not induced by any of the IMOs. These results indicate that in canine PBMC from healthy dogs, IMO1 was able to induce a T(H)-1 immune response including T- and B-cell proliferation.
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Affiliation(s)
- Michelle Im Hof
- Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggassstrasse 128, CH-3012 Bern, Switzerland.
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Werling D, Coffey TJ. Pattern recognition receptors in companion and farm animals - the key to unlocking the door to animal disease? Vet J 2006; 174:240-51. [PMID: 17137812 PMCID: PMC7110490 DOI: 10.1016/j.tvjl.2006.10.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2006] [Revised: 08/07/2006] [Accepted: 10/04/2006] [Indexed: 01/27/2023]
Abstract
The innate immune system is essential for host defence and is responsible for early detection of potentially pathogenic microorganisms. Upon recognition of microbes by innate immune cells, such as macrophages and dendritic cells, diverse signalling pathways are activated that combine to define inflammatory responses that direct sterilisation of the threat and/or orchestrate development of the adaptive immune response. Innate immune signalling must be carefully controlled and regulation comes in part from interactions between activating and inhibiting signalling receptors. In recent years, an increasing number of pattern recognition receptors (PRRs), including C-type lectin receptors and Toll-like receptors (TLRs), has been described that participate in innate recognition of microbes, especially through the so called pathogen-associated molecular patterns (PAMPs). Recent studies demonstrate strong interactions between signalling through these receptors. Whereas useful models to study these receptors in great detail in the murine and human system are now emerging, relatively little is known regarding these receptors in companion and farm animals. In this review, current knowledge regarding these receptors in species of veterinary relevance is summarised.
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Affiliation(s)
- Dirk Werling
- Royal Veterinary College, Department of Pathology and Infectious Diseases, Hawkshead Lane, Hatfield AL9 7TA, UK.
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Stokes C, Waly N. Mucosal defence along the gastrointestinal tract of cats and dogs. Vet Res 2006; 37:281-93. [PMID: 16611548 DOI: 10.1051/vetres:2006015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Accepted: 01/09/2006] [Indexed: 11/15/2022] Open
Abstract
Diseases that are associated with infections or allergic reactions in the gastrointestinal and respiratory tracts are major causes of morbidity in both cats and dogs. Future strategies for the control of these conditions require a greater understanding of the cellular and molecular mechanisms involved in the induction and regulation of responses at the mucosal surfaces. Historically, the majority of the fundamental studies have been carried out in rodents or with tissues obtained from man, but the expanding range of reagents available for the study of farm and companion animals provides opportunities for study in a wider range of animals including cats and dogs. To date, these studies have tended to be focussed on characterising the cellular distributions in healthy animals and in groups of cats and dogs identified as having an increased risk of mucosal disturbance. Where species comparisons of mucosal immune systems have been made, the results have tended to be divided between monogastric and ruminant animals. It is then not surprising that the mucosal immune systems of both cats and dogs bear greatest similarity to that documented for man and pigs. For example, IgA is the dominant immunoglobulin in mucosal secretions of cats and dogs and oral tolerance can be induced following the introduction of novel antigens into the diet. Also like several other species, cats become transiently hypersensitive to the newly introduced dietary antigen prior to the establishment of tolerance. In contrast, there are a number of potentially important differences. In particular, there are significant differences between cats and dogs in the expression MHC class II molecules on gut epithelial cells. Similarly, it has been reported that cats have elevated numbers of intraepithelial lymphocytes (IEL) and that a proportion of these express surface IgM. It remains to be determined if these differences reflect the way in which the animals are maintained and if they may have greater biological significance.
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Affiliation(s)
- Chris Stokes
- Division of Veterinary Pathology Infection and Immunity, School of Clinical Veterinary Science, University of Bristol, Langford House, Langford, BS40 5DU, United Kingdom.
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