Functional analysis of human T cell subsets defined by monoclonal antibodies. IV. Induction of suppressor cells within the OKT4+ population.

Abstract

The functional heterogeneity within the [mouse monoclonal antibody] OKT4+ subset of human T cells was explored. Although in vitro pokeweed mitogen-activated OKT4+ cells can function as radioresistant helper cells, these activated OKT4+ cell could also exert potent feedback suppression. Despite the induction of suppressor cells after pokeweed mitogen activation, the OKT4+ population maintains its original OKT3+, OKT4+ and OKT8- surface phenotype. The suppressor cells contained within the activated OKT4+ population were radiosensitive. Importantly, the suppression mediated by activated OKT4+ cells required the presence of radiosensitive cells contained within the resting OKT4+ population. The OKT4+ subset of human T cells probably contains cells that can be activated to differentiate into suppressor cells independent of OKT8+ cells.