title: In vivo lipopolysaccharide injection alters CD4+CD25+ cell properties in chickens.
abstract: In chickens, thymic CD4(+)CD25(+) cells are characterized as regulatory T cells. The objectives of this experiment were to study the effects of an in vivo lipopolysaccharide (LPS) injection on the percentage of CD4(+)CD25(+) cells in peripheral organs and the suppressive properties of splenic CD4(+)CD25(+) cells in chickens. Chickens were injected with LPS and CD4(+)CD25(+) cells were analyzed at 1, 2, 3, 5, and 10 d post LPS injection. The LPS injection increased CD4(+)CD25(+) cell percentage approximately 5-fold in the blood at 1 d post LPS injection (P < 0.001), 3-fold in the thymus at 3 d post LPS injection (P = 0.001), and 2.5-fold in the spleen at 2 d post LPS injection (P = 0.001) compared with the no-LPS-injected group. The LPS injection did not alter the CD4(+)CD25(+) cell percentage in the cecal tonsil (P = 0.162), lung (P = 0.098), or bone marrow (P = 0.071) at any time point measured. At 2 d post LPS injection, splenic CD4(+)CD25(+) cells lost their suppressive ability (P < 0.001). At 5 d post LPS injection, splenic CD4(+)CD25(+) cells not only regained their suppressive ability, but also became supersuppressive (P < 0.001). Splenic CD4(+)CD25(+) cells at 5 d post LPS injection produced 5.5-fold more (P = 0.005) IL-10 mRNA than splenic CD4(+)CD25(+) cells at 0 and 2 d post LPS injection. In conclusion, chicken regulatory T cells are differentially activated to facilitate immune response during the early stage of inflammation and to facilitate immune suppression at a later stage of inflammation.
authors.affiliation: Department of Animal Sciences, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA.
authors.forename: R
authors.initials: R
authors.lastname: Shanmugasundaram
authors.forename: R K
authors.initials: RK
authors.lastname: Selvaraj
mesh_terms: D000818:Animals; D000906:Antibodies; D015704:CD4 Antigens / Q000235:genetics / Q000378:metabolism*; D002645:Chickens / Q000276:immunology*; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D007376:Interleukin-2 / Q000235:genetics / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000235:genetics / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000633:toxicity*; D008221:Lymphoid Tissue / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000187:drug effects* / Q000502:physiology*
chemical_list: D000906:Antibodies; D015704:CD4 Antigens; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D016753:Interleukin-10