Frequency analysis of CD4+CD8+ T cells cloned with IL-4.
The coexpression of both CD4 and CD8 molecules on T cells occurs in the peripheral blood at a low frequency and can be generated transiently on CD4+ peripheral blood T cells by treatment with lectin which induces CD8 biosynthesis and cell surface expression. We have cloned T cells in a nonselective fashion from normal subjects in the presence of either IL-2, rIL-4 and IL-2, or rIL-4 and have examined the phenotypic expression of CD4 and CD8. The addition of excess rIL-4 increased the expression of CD8 on the surface of CD4+ T cell clones but did not increase CD4 expression on CD8+ T cell clones. There were three patterns of CD4 and CD8 expression observed: high density CD8 with no CD4 expression; high density CD4 with low CD8 expression; or high density CD4 with higher cell surface CD8 expression which was regulated by the presence of rIL-4. CD4+ T cell clones originally cultured in IL-2 and rIL-4 and subsequently grown in IL-2 alone exhibited decreased expression of the CD8 molecule. The increased expression of CD8 did not correlate with NK activity or lectin-dependent cytotoxicity in an antigen independent system. In addition, rIL-4 alone or in combination with IL-2 appeared to accelerate the growth curve of T cell clones as compared to IL-2 alone. These results show that IL-4 can upregulate CD8 expression on CD4+ T cell clones while not effecting CD4 expression on CD8+ T cell clones. As class I MHC is the ligand for the CD8 molecule, expression of CD8 induced by IL-4 on CD4+ T cells may allow for increased nonspecific cell to cell contact during the course of an inflammatory response.
Brod
S A
SA
Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115.
Purvee
M
M
Benjamin
D
D
Hafler
D A
DA
D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D015704:CD4 Antigens / Q000032:analysis*; D016827:CD8 Antigens; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*
D000945:Antigens, Differentiation, T-Lymphocyte; D015704:CD4 Antigens; D016827:CD8 Antigens; D007376:Interleukin-2; D011994:Recombinant Proteins; D015847:Interleukin-4