Thymic T cells are driven to expand upon interaction with self-class II major histocompatibility complex gene products on accessory cells.
Murine thymocytes induce the monokine interleukin 1 upon in vitro coculture with a radioresistant Ia-bearing accessory cell [murine Ia molecule is a class II major histocompatibility complex (MHC) antigen]. The generation of interleukin 1 is critically dependent on the function of I-region gene products on accessory cells. The induced interleukin 1 appears to allow the activation and proliferation of self-MHC-specific thymocytes. Thus, in the absence of added exogenous factors, there is an Ia-dependent thymocyte proliferation. This selective activation of thymocytes is observed with both mature and immature thymic T cells. This in vitro response results in the selective amplification of developing T cells with self-MHC specificity and could be of importance to the in vivo commitment of T cells to MHC determinants that occurs in the thymus.
D000818:Animals; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D004261:DNA Replication; D005260:Female; D007375:Interleukin-1 / Q000235:genetics*; D007376:Interleukin-2 / Q000235:genetics*; D007700:Kinetics; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D051379:Mice; D008815:Mice, Inbred Strains; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
D000911:Antibodies, Monoclonal; D007375:Interleukin-1; D007376:Interleukin-2