title: Differentiation of prothymocytes induced by trypsin.
abstract: Treatment in vitro of nude mouse spleen prothymocytes with relatively low concentrations (1-50 micrograms/ml) of trypsin induce the Thy 1- to Thy 1+ conversion. The effect of trypsin was inhibited by prior heating or by addition of soybean trypsin inhibitor. The maximal effect achieved by trypsin treatment, approximately 25% conversion of spleen cells from layer B of an albumin gradient into theta-positive cells, was equivalent to that obtained with thymic hormone preparation (TP-1) at 10 ng/ml. Maximal conversion required 120 min incubation with TP-1 or trypsin. We conclude that both trypsin and TP-1 act by perturbation of a membrane receptor which can send a signal initiating the differentiation process.
mesh_terms: D000818:Animals; D000954:Antigens, Surface; D002454:Cell Differentiation / Q000187:drug effects; D003602:Cytotoxicity, Immunologic; D005260:Female; D051379:Mice; D008819:Mice, Nude; D013154:Spleen / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D018800:Thy-1 Antigens; D013949:Thymus Extracts / Q000494:pharmacology; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D000954:Antigens, Surface; D018800:Thy-1 Antigens; D013949:Thymus Extracts; C031407:thymostimulin; D014357:Trypsin