IL-2 and IL-4 stimulate different subpopulations of double-negative thymocytes.
Double-negative (CD4-/CD8-) thymocytes from young adult mice can be separated into two distinct subpopulations on the basis of the binding of mAb 7D4 directed against the receptor for IL-2. The 7D4+ cells have predominantly nonrearranged TCR beta-chain genes and express incomplete 1.0-kb beta-messages, whereas the 7D4- cells have rearranged beta-genes and express complete 1.3-kb as well as incomplete 1.0-kb beta-messages. These two populations of double-negative thymocytes also differ in their responses to IL-2 and IL-4. The 7D4+ cells are nonresponsive to IL-2 alone or IL-2 plus PMA but they are stimulated to proliferate by the combination of IL-4 and PMA. In contrast, the 7D4- cells vigorously proliferate in response to IL-2 alone or IL-2 plus PMA but they respond poorly to IL-4 alone or IL-4 plus PMA. These results suggest that IL-2 and IL-4 may be involved in the stimulation of immature thymocytes at distinct steps of their differentiation. IL-4 together with PMA stimulate immature thymocytes which seem to express the IL-2R but do not respond to IL-2.
Takei
F
F
Department of Pathology, University of British Columbia, Vancouver, Canada.
D000818:Animals; D002469:Cell Separation; D007376:Interleukin-2 / Q000494:pharmacology*; D015847:Interleukin-4; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D013601:T-Lymphocytes / Q000145:classification* / Q000276:immunology / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007376:Interleukin-2; D007378:Interleukins; D011948:Receptors, Antigen, T-Cell; D015847:Interleukin-4; D013755:Tetradecanoylphorbol Acetate