title: In vitro induction of Lyt surface markers on precursor cells incubated with thymosin polypeptides.
abstract: Induction of precursor T cells by thymosin fraction 5 was found to generate a population of cells bearing the Lyt 1+, 2+, and 3+ phenotype and functionally capable of providing T-cell helper activity in vitro. However, when the component polypeptides of thymosin fraction 5 were similarly analyzed, several displayed inductive activities quite different from those of the parent preparation. These results suggest that variations in the polypeptide composition determine, to a large part, the inductive properties of a thymosin preparation and that such variations in vivo may serve as a regulatory system for T-cell maturation.
mesh_terms: D000818:Animals; D000954:Antigens, Surface; D001854:Bone Marrow Cells; D002454:Cell Differentiation / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D010455:Peptides / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D013947:Thymosin / Q000494:pharmacology*; D013951:Thymus Hormones / Q000494:pharmacology*
chemical_list: D000954:Antigens, Surface; D010455:Peptides; D013951:Thymus Hormones; D013947:Thymosin