title: Presence of CD8 alpha-CD8 beta-positive TcR gamma/delta thymocytes in the fetal murine thymus and their in vitro expansion with interleukin-7.
abstract: Several groups have described that a low percentage of in vitro cultured T cell receptor (TcR) gamma/delta cells express CD8. Contrary to TcR alpha/beta cells, however, CD8 on these TcR gamma/delta cells was shown to be a CD8 alpha homodimer. We describe here that addition of interleukin-7 (IL-7) to a short-term in vitro culture of fetal day 14 thymic lobes in an organ culture system or of fetal day 18 fetal thymocytes in cell suspension yields CD8 beta-positive TcR gamma/delta cells. This is not the result of IL-7-induced expression of CD8 beta on previously CD8 beta-negative cells. It is due to IL-7-induced expansion of CD8 alpha-CD8 beta-positive TcR gamma/delta cells which are shown to be present in the starting fetal thymocyte cell population.
authors.affiliation: Laboratory of Bacteriology, Virology and Immunology, University Hospital, Ghent, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Leclercq
authors.forename: M
authors.initials: M
authors.lastname: De Smedt
authors.forename: J
authors.initials: J
authors.lastname: Plum
mesh_terms: D000818:Animals; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis*; D002478:Cells, Cultured; D005260:Female; D005333:Fetus / Q000276:immunology; D015851:Interleukin-7 / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009924:Organ Culture Techniques; D011247:Pregnancy; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens; D015851:Interleukin-7; D016692:Receptors, Antigen, T-Cell, gamma-delta; D011994:Recombinant Proteins