A gamma/delta cell receptor heterodimer induces the expression of CD4 and CD8 in thymocytes.
CD4 and CD8 have been useful surface markers for alpha/beta T cell maturation. In an alpha/beta T cell receptor (TCR) transgenic SCID mice system, it has been shown that alpha/beta TCR alone is sufficient to induce CD4 and CD8 surface expression on thymic T cells. Although the late embryonic thymic gamma/delta T cells are predominately single and double positive, it has not been clear if gamma/delta TCR has a similar capacity. In this study, we show that when transgenes encoding the earliest embryonic gamma/delta TCR are coexpressed with the SCID defect, the gamma/delta transgenes promote the appearance of both the CD4-8- and CD4+8+ T cells in the thymus. Furthermore, the expression of CD4 and CD8 does not require continuous surface gamma/delta TCR expression. These results indicate that gamma/delta TCR alone can promote the CD4/8 surface expression, and may suggest a role for gamma/delta T cells in initiating normal thymic ontogeny.
Iwashima
M
M
Department of Microbiology and Immunology, Stanford University, California 94305.
Davis
M M
MM
Chien
Y H
YH
D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics*; D015704:CD4 Antigens / Q000235:genetics*; D016827:CD8 Antigens; D005434:Flow Cytometry; D007153:Immunologic Deficiency Syndromes / Q000235:genetics / Q000276:immunology; D046911:Macromolecular Substances; D051379:Mice; D008809:Mice, Inbred C3H; D008817:Mice, Mutant Strains; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000502:physiology*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
D000945:Antigens, Differentiation, T-Lymphocyte; D015704:CD4 Antigens; D016827:CD8 Antigens; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell