Lifespan of gamma/delta T cells.
Information on the turnover and lifespan of murine gamma/delta cells was obtained by administering the DNA precursor, bromodeoxyuridine (BrdU), in the drinking water and staining lymphoid cells for BrdU incorporation. For TCR-gamma/delta (Vgamma2) transgenic mice, nearly all gamma/delta thymocytes became BrdU+ within 2 d and were released rapidly into the peripheral lymphoid tissues. These recent thymic emigrants (RTEs) underwent phenotypic maturation in the periphery for several days, but most of these cells died within 4 wk. In adult thymectomized (ATx) transgenic mice, only a small proportion of gamma/delta cells survived as long-lived cells; most of these cells had a slow turnover and retained a naive phenotype. As in transgenic mice, the majority of RTEs generated in normal mice (C57BL/6) appeared to have a restricted lifespan as naive cells. However, in marked contrast to TCR transgenic mice, most of the gamma/delta cells surviving in ATx normal mice had a rapid turnover and displayed an activated/memory phenotype, implying a chronic response to environmental antigens. Hence, in normal mice many gamma/delta RTEs did not die but switched to memory cells.
Tough
D F
DF
Department of Immunology, IMM4, The Scripps Research Institute, La Jolla, California 92037, USA.
Sprent
J
J
D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D016922:Cellular Senescence / Q000502:physiology*; D005434:Flow Cytometry; D007700:Kinetics; D008214:Lymphocytes / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D008822:Mice, Transgenic; D010641:Phenotype; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics* / Q000378:metabolism; D013601:T-Lymphocytes / Q000145:classification / Q000378:metabolism / Q000502:physiology*; D013934:Thymectomy
D016692:Receptors, Antigen, T-Cell, gamma-delta; D001973:Bromodeoxyuridine