Proliferation in vitro of Lyt2-,L3T4- thymocytes shows responsiveness to interleukin 1.
The responsiveness of adult mouse thymocytes to interleukin 1 (IL-1) was investigated. When stimulated with suboptimal concentrations of ionomycin and phorbol myristate acetate (PMA), the immature subpopulation of Lyt2-,L3T4- (2-4-) thymocytes responded to exogenous, purified IL-1 in a dose-dependent manner. In contrast, mature lymph node (LN) T cells were unresponsive to exogenous IL-1 under similar conditions. The proliferation of 2-4- thymocytes, which comprise 2-3% of cells in the adult mouse thymus, was independent of exogenous IL-2 and accounted for essentially all the 3H-thymidine incorporation by unfractionated thymocytes in response to IL-1. Optimally stimulated 2-4- cells did not show responsiveness to exogenous IL-1, and 48 h supernatants from these cultures were found to contain IL-1 like activity. Taken together, the data point to a role for IL-1 in the proliferation of immature 2-4- cells in the thymus.
Chaudhri
G
G
Department of Experimental Pathology, John Curtin School of Medical Research, Canberra, Australia.
Clark
I A
IA
Ceredig
R
R
D000818:Animals; D000943:Antigens, Differentiation / Q000032:analysis; D000950:Antigens, Ly / Q000032:analysis; D002455:Cell Division; D002478:Cells, Cultured; D005260:Female; D007375:Interleukin-1 / Q000096:biosynthesis / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000166:cytology*; D013950:Thymus Gland / Q000276:immunology*
D000943:Antigens, Differentiation; D000950:Antigens, Ly; D007375:Interleukin-1; D007376:Interleukin-2