Transgenic expression of interleukin 7 restores T cell populations in nude mice.
The thymic lesion of the nude mouse causes a profound block in T cell development. The failure of most T cells to mature in nude mice is likely to reflect a requirement for signals elaborated in the normal thymus. Interleukin 7 (IL-7), a lymphokine that is normally expressed in the thymus and has been implicated in T cell maturation, might be central to this process. To test this possibility, we introduced a transgene directing lymphoid expression of IL-7 into nude mice and found that it substantially alleviates the block in T cell maturation caused by the thymic defect. IL-7 transgenic nude mice have increased numbers of peripheral cells expressing the T cell marker Thy-1, the T cell antigen receptor complex, and the co-receptors CD4 and CD8. The IL-7 transgene also restores T cell-specific proliferation and activation responses to the peripheral cells of transgene-rescued nude mice. Such findings point toward a fundamental role for IL-7 in the thymic maturation of T cells.
Rich
B E
BE
Department of Genetics, Harvard Medical School, Boston, Massachusetts.
Leder
P
P
D000818:Animals; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D015851:Interleukin-7 / Q000235:genetics* / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008822:Mice, Transgenic; D051381:Rats; D013601:T-Lymphocytes / Q000502:physiology*
D015704:CD4 Antigens; D016827:CD8 Antigens; D015851:Interleukin-7