Intraepithelial Lymphocytes: To Serve and Protect
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The mucosal immune system is constantly exposed to a wide range of commensal and potentially pathogenic microbial species. Chronic exposure to foreign organisms makes generation of an appropriate immune response critical in maintaining a balance between elimination of harmful pathogens, peaceful coexistence with commensals, and prevention of autoimmunity. Intestinal intraepithelial lymphocytes provide a first line of defense at this extensive barrier with the outside world, and as such, understanding their role in immunity is critical.
KeywordsMucosal immunology Intraepithelial lymphocyte CD8αβ T cell γδ T cell T-cell migration Immunologic memory Intestinal homeostasis Microbial surveillance
Conflicts of interest: Dr. Sheridan’s institution has received grants from the Crohn’s and Colitis Foundation of America. Dr. Lefrançois’s laboratory has received grants from the National Institutes of Health.
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