title: Two Ly-2 T helper cell subsets distinguished by Qa-1 phenotype. The priming environment determines whether one or both subsets will be generated.
abstract: The Qa-1 cell surface phenotype reportedly distinguishes two Ly-1 T cell subsets conjointly required for T helper effector activity. Ly-1 cells, obtained from several different priming regimens, were negatively selected with anti-Qa-1 plus complement and compared with unselected Ly-1 cells for helper cell activity. Priming isolated T cells on antigen-pulsed macrophages in the absence of B cells favors the generation of the Ly-1:Qa1- subset, which is capable of efficient helper activity in the absence of the Ly-1:Qa-1+ subset. Priming T cells in an environment containing B cells generates both Ly-1:Qa-1- helper effector cells and Ly-1:Qa-1+ cells which contribute to the helper effect. Whether Ly-1:Qa-1+ cells are capable of independent helper activity cannot be determined, and, as such, Ly-1:Qa-1+ cells are more appropriately termed "help associated" rather than "helper effector." Our results assign a membrane phenotype, Qa-1, which distinguishes an Ly-1 help-associated B cell requiring subset in our system and may prove to be a general marker in a number of systems of Ly-1 inducer cell subsets which functionally require or recognize B cells or their products.
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000145:classification* / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D002469:Cell Separation; D003348:Cortisone / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D010641:Phenotype; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification* / Q000166:cytology / Q000276:immunology
chemical_list: D000950:Antigens, Ly; D003348:Cortisone