title: A novel peripheral CD4+ CD8+ T cell population: inheritance of CD8alpha expression on CD4+ T cells.
abstract: In this study we show the inheritance of a CD4+ CD8+ peripheral Tcell population in the H.B15 chicken strain. A large proportion of alphabeta T cells in peripheral blood (20-40%), spleen (10-20%) and intestinal epithelium (5-10%) coexpress CD4 and CD8alpha, but not CD8beta. CD4+ CD8alpha alpha cells are functionally normal T cells, since they proliferate in response to mitogens and signals delivered via the alphabeta T cell receptor as well as via the CD28 co-receptor. These cells induce in vivo a graft versus host-reaction, providing further evidence for their function as CD4+ T cells. The CD4+ CD8alpha alpha T cell population was found in 75% of the first progeny and in 100% of further progenies, demonstrating that coexpression of CD4 and CD8 on peripheral T cells is an inherited phenomenon. In addition, cross-breeding data suggest a dominant Mendelian form of inheritance. The hereditary expression of CD8alpha on peripheral CD4+ T cells in chicken provides a unique model in which to study the regulation of CD4 and CD8 expression.
authors.affiliation: Turku Immunology Center, Department of Medical Microbiology, Turku University, Finland. marko.luhtala@utu.fi
authors.forename: M
authors.initials: M
authors.lastname: Luhtala
authors.forename: O
authors.initials: O
authors.lastname: Lassila
authors.forename: P
authors.initials: P
authors.lastname: Toivanen
authors.forename: O
authors.initials: O
authors.lastname: Vainio
mesh_terms: D000818:Animals; D001483:Base Sequence; D015704:CD4 Antigens / Q000032:analysis*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016827:CD8 Antigens / Q000032:analysis* / Q000235:genetics; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002469:Cell Separation; D002645:Chickens; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D006087:Graft vs Host Reaction; D016130:Immunophenotyping; D008213:Lymphocyte Activation; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens; D012333:RNA, Messenger