title: Separate T cell subclasses inducing or attenuating graft-versus-host reaction.
abstract: The subclasses of chicken T cells capable of initiating or regulating graft-versus-host reaction (GVHR) were studied. T cells isolated from spleens of bursectomized agammaglobulinemic chickens were rosetted to separate the TG cells bearing the chicken IgG-Fc membrane receptor from those TG- cells lacking the receptor. The GVH reactivity of these subclasses was quantified by their capacity to induce pock lesions on chorioallantoic membranes of allogeneic chick embryos after their implantation on the membranes. Cells of TG- and unseparated T cell preparations but not TG cells were shown to be capable of inducing GVHR. TG- cells, obtained after the depletion of TG from unseparated T cell preparations exhibited increased GVH reactivity over that of unseparated T cells. Addition of TG cells to TG- cell preparations attenuated the TG- cell-induced GVHR. The degree of suppression was in proportion to the number of TG added to the inoculum. The GVH inducer cells were shown to be radiosensitive, being incapable of initiating the reaction after exposure to 300 rad of gamma-radiation. The suppressive activity of TG cells was unchanged after high dosage radiation. The possibility that TG cells regulate GVHR via a suppression of cellular proliferation is discussed.
mesh_terms: D000482:Allantois / Q000473:pathology; D000818:Animals; D002469:Cell Separation; D002642:Chick Embryo; D002645:Chickens; D003602:Cytotoxicity, Immunologic; D006087:Graft vs Host Reaction; D007111:Immunity, Cellular; D011817:Rabbits; D011947:Receptors, Antigen, B-Cell; D013601:T-Lymphocytes / Q000145:classification* / Q000528:radiation effects
chemical_list: D011947:Receptors, Antigen, B-Cell