Regulatory T cell properties of thymic CD4+CD25+ cells in ducks.
Thymic CD4(+)CD25(+) cells from ducks were characterized for mammalian T regulatory cells' suppressive and cytokine production properties. The cross reactivity of anti-chicken CD25 monoclonal antibody with duck CD25 was confirmed by evaluating Concanavalin-A-stimulated CD25 upregulation in splenocytes. CD4(+)CD25(+) cells were detectable in the thymus, spleen, cecal tonsil, and lung (airsacs), but not in the bursa. Duck CD4(+)CD25(+) cells had approximately nine-fold higher IL-10 mRNA, 12-fold higher TGF-β, 16-fold higher CTLA-4, and nine-fold higher LAG-3 mRNA amounts than thymic CD4(+)CD25(-) cells. Thymic CD4(+)CD25(+) cells had no detectable levels of IL-2 mRNA. Duck CD4(+)CD25(+) cells had a three-fold higher IL-10 mRNA amount than chicken CD4(+)CD25(+) cells. Duck CD4(+)CD25(+) cells were anergic in vitro. Duck CD4(+)CD25(+) cells suppressed naive cell proliferation at effector: responder cell ratios above 0.5:1 in both contact-dependent and -independent pathways. It could be concluded that thymic CD4(+)CD25(+) cells in ducks are most likely the counterpart of mammalian T regulatory cells.
Department of Animal Sciences, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA.
Revathi
R
Shanmugasundaram
Ramesh K
RK
Selvaraj
D000818:Animals; D015153:Blotting, Western; D060908:CTLA-4 Antigen / Q000235:genetics / Q000276:immunology; D004372:Ducks / Q000097:blood / Q000276:immunology*; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology; D007376:Interleukin-2 / Q000235:genetics / Q000276:immunology; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology*; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000276:immunology
D060908:CTLA-4 Antigen; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D016212:Transforming Growth Factor beta; D016753:Interleukin-10; D012313:RNA