Cytochemical analysis of human peripheral blood lymphocyte subsets defined by monoclonal antibodies.

Human blood lymphocyte subpopulations, revealed by a panel of commercially available monoclonal antibodies by means of a rosetting technique, were submitted to direct cytochemical analysis and were shown to have distinguishing characteristics. T cells reactive with OKT3 antibody (T3+) displayed higher beta-glucuronidase and dot-like alpha-naphthyl acetate acid esterase (ANAE) activity than T3- cells. Helper/inducer cells (T4+) were characterized by a high level of dot-like ANAE activity, whereas cytotoxic/suppressor cells (T8+) displayed selective naphthol-ASD-chloroacetate esterase activity. These results provide evidence for association of some cytoplasmic enzyme activities with the expression of membrane differentiation markers defined by monoclonal antibodies.