Gamma delta T cells promote CD4 and CD8 expression by SCID thymocytes.
Molecular studies of the gamma delta TCR, which is expressed by a minor subpopulation of T lymphocytes in all vertebrate species, have defined a subset which expresses a receptor with extreme junctional diversity and a second subset, most commonly found in epithelia, which expresses a receptor of very limited diversity. In the developing murine thymus, gamma delta T cells appear in an ordered sequence of specific V rearrangements, V gamma 3V delta 1 on day 14, V gamma 2V delta 1 on day 17, and subsequently V gamma 4V delta 5, V delta 6, or V delta 7. We demonstrate that the transfer of expanded populations of gamma delta cells from newborn thymus and cell lines expressing the invariant V gamma 3V delta 1 receptor into SCID mice, which lack T and B cells, results in the appearance of CD3-CD4+CD8+ thymocytes. Thus, one role of the early appearing V gamma 3V delta 1 T cells in thymic development in vivo is to promote CD4 and CD8 surface expression on precursor cells.
Lynch
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F
Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892.
Shevach
E M
EM
D000818:Animals; D015704:CD4 Antigens / Q000032:analysis*; D016827:CD8 Antigens / Q000032:analysis*; D002454:Cell Differentiation; D051379:Mice; D016513:Mice, SCID; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology*
D015704:CD4 Antigens; D016827:CD8 Antigens; D016692:Receptors, Antigen, T-Cell, gamma-delta