Autologous Mixed Lymphocyte Reaction in Man.

Abstract

Human peripheral blood T lymphocytes were separated into theophylline-resistant (TR) and -sensitive (TS) subpopulations. Proliferative responses of TR, TS and unfractionated T cells were studied, using irradiated autologous or allogeneic non-T cells as stimulators. TR cells proliferated vigorously in both autologous and allogeneic mixed lymphocyte cultures (MLC). TS cells, which constitute .apprx. 20% of unfractionated T cells, exhibited poor proliferative responses to autologous and allogeneic stimulation. The magnitude of proliferation in autologous and in allogenic MLC was found to be directly dependent on the number of TR cells in the culture. Mitomycin-C(MMC)-treated TR cells augmented and MMC-treated TS cells suppressed (P < 0.05) the autologous and allogeneic MLC responses of unfractionated T cells. The response of TS cells did not increase in autologous or allogeneic MLC when co-cultured with MMC-treated TR cells. MMC-treated TS cells, when co-cultured with TR cells, suppressed the responses of TR cells (P < 0.05). The enhancing effect of TR cells was radiation-resistant. Suppressor influence of TS cells was abolished by irradiation (P < 0.05). TR cells apparently are the responding cells in autologous mixed lymphocyte reaction and augment the MLC responses of unfractionated T cells. TS cells respond poorly in autologous or allogeneic MLC and suppress the response of TR cells.