Surface markers of cloned human T cells with helper or suppressor activity on pokeweed mitogen‐driven B cell differentiation

摘要

AbstractHuman spleen T cells stimulated with pokeweed mitogen (PWM) were cloned under limiting conditions in microculture systems using interleukin 2 and irradiated autologous cells. Clones were screened for helper or suppressor activity on PWM‐dependent B cell differentiation by adding cell aliquots to either isolated B cells and PWM or to mixtures of T and B cells and PWM. Out of 97 clones tested, 14 promoted intense B cell differentiation, as assessed by measurements of secreted IgG, and 6 strongly inhibited B cell maturation induced by spleen T cells.All the selected clones maintained their original activity after shortterm clonal expansion; in addition, a similar (helper or suppressor) effect was detected when the total number of plasma cells per well was evaluated. Suppressor clones had no cytolytic activity on autologous T and B cell blasts, K562 cells or antibody‐coated L 1210 mouse cells. Nine helper and 6 suppressor clones were analyzed for a battery of surface markers. All the clones were E rosette‐positive and expressed HLA‐DR (Ia) antigens. Fcμ eptor was present on a single helper clone, whereas Fcγ receptor was expressed on a suppressor clone only. All but two clones expressed the OKT4+/ OKT8−, a single suppressor clone was OKT8+/OKT4−, whereas coexpression of OKT4 and OKT8 antigens was detected in one helper clone. Thus, the claim that helper T cells are OKT4+/OKT8−and suppressor T cells are OKT4−/OKT8+is not supported by the analysis of their phenotype at