Regulatory T cell properties of chicken CD4+CD25+ cells.
Chicken CD4(+)CD25(+) cells were characterized for mammalian regulatory T cells' suppressive and cytokine production properties. Anti-chicken CD25 mAb was produced in mice and conjugated with a fluorescent tag. The specificity of the Ab against chicken CD25 was confirmed by evaluating Con A-induced CD25 upregulation in thymocytes and by quantifying the CD25 mRNA content of positive and negative cells identified by anti-chicken CD25 Ab. The percentage of CD4(+)CD25(+) cells, expressed as a percentage of CD4(+) cells, in thymus and blood was ∼3-7%, in spleen was 10%, and in cecal tonsil, lung, and bone marrow was ∼15%. Bursa had no detectable CD4(+)CD25(+) cells. CD25(+) cells were mostly CD4(+) in the thymus, whereas in every other organ studied, CD25(+) cells were distributed between CD4(+) and CD4(-) cells. Chicken thymic CD4(+)CD25(+) cells did not proliferate in vitro in the absence of recombinant chicken IL-2 (rCIL-2). In the presence of rCIL-2, PMA plus ionomycin or Con A stimulated CD4(+)CD25(+) cell proliferation, whereas anti-CD3 plus CD28 did not stimulate CD4(+)CD25(+) cell proliferation. Naive CD4(+)CD25(+) cells had 29-fold more IL-10 mRNA and 15-fold more TGF-β mRNA than the naive CD4(+)CD25(-) cells. Naive CD4(+)CD25(+) had no detectable IL-2 mRNA. Both naive and PMA plus ionomycin-stimulated thymic CD4(+)CD25(+) cells suppressed naive T cell proliferation. The suppressive properties were partially contact dependent. Supplementing CD4(+)CD25(+) cell coculture with rCIL-2 reversed the suppressive properties of CD4(+)CD25(+) cells. Chicken CD4(+)CD25(+) cells have suppressive properties similar to that of mammalian regulatory T cells.
Department of Animal Sciences, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA.
Revathi
R
Shanmugasundaram
Ramesh K
RK
Selvaraj
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000918:Antibody Specificity; D015704:CD4 Antigens / Q000096:biosynthesis*; D019556:COS Cells; D002450:Cell Communication / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D002645:Chickens; D002522:Chlorocebus aethiops; D018920:Coculture Techniques; D016207:Cytokines / Q000096:biosynthesis; D007108:Immune Tolerance / Q000276:immunology*; D053645:Interleukin-2 Receptor alpha Subunit / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D009928:Organ Specificity / Q000276:immunology; D012333:RNA, Messenger / Q000096:biosynthesis; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015854:Up-Regulation / Q000276:immunology
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016207:Cytokines; D053645:Interleukin-2 Receptor alpha Subunit; D012333:RNA, Messenger