Disparities in TLR5 Expression and Responsiveness to Flagellin in Equine Neutrophils and Mononuclear Phagocytes
| Autor: | Michel L. Vandenplas, James N. Moore, Andrew T. Gewirtz, Soyoung Kwon, David J. Hurley, Tom P. Robertson |
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| Rok vydání: | 2011 |
| Předmět: |
Lipopolysaccharides
Salmonella typhimurium Time Factors Neutrophils Blotting Western Immunology Gene Expression Biology Peripheral blood mononuclear cell Proinflammatory cytokine Microbiology Macrophages Alveolar Animals Immunology and Allergy Horses Cells Cultured Phagocytes Innate immune system Dose-Response Relationship Drug Reverse Transcriptase Polymerase Chain Reaction Tumor Necrosis Factor-alpha Flow Cytometry Molecular biology Interleukin-10 Toll-Like Receptor 5 Interleukin 10 TLR5 Leukocytes Mononuclear Macrophages Peritoneal TLR4 biology.protein Tumor necrosis factor alpha Reactive Oxygen Species Flagellin |
| Zdroj: | The Journal of Immunology. 186:6263-6270 |
| ISSN: | 1550-6606 0022-1767 |
| DOI: | 10.4049/jimmunol.1003824 |
| Popis: | As sentinel cells of the innate immune system, neutrophils and mononuclear phagocytes use specific TLRs to recognize the conserved molecular patterns that characterize microbes. This study was performed to compare the responses of equine neutrophils and mononuclear phagocytes to LPS and flagellin, components of bacteria that are recognized by TLR4 and TLR5, respectively. Neutrophils and mononuclear phagocytes isolated from healthy horses were incubated in vitro with LPS, flagellin, or pronase-inactivated flagellin in the presence or absence of polymyxin B. Production of reactive oxygen species and expression of mRNA for proinflammatory cytokines were used as readouts for activation of neutrophils; production of TNF-α was used for the mononuclear cells. Western blot analysis and flow cytometry were used to detect TLR5 protein in both cell types. Although the neutrophils responded to both LPS and flagellin by producing reactive oxygen species and expressing mRNA for proinflammatory cytokines, flagellin had no stimulatory effect on monocytes or macrophages. Although both neutrophils and monocytes expressed mRNA for TLR5, it appeared to be translated into protein only by the neutrophils. Incubation with neither LPS nor IFN-γ altered TLR5 expression by the monocytes. These findings indicate that flagellin has disparate effects on neutrophils and mononuclear phagocytes isolated from horses, a species that is exquisitely sensitive to the TLR4 ligand, LPS, and that equine mononuclear phagocytes, unlike corresponding cells of other mammalian species, lack surface expression of TLR5 and do not respond to flagellin. |
| Databáze: | OpenAIRE |
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