A simple and rapid flow cytometric method to measure lymphocyte activation in HIV+ subjects. Diminished response to pokeweed mitogen in early disease.

: It was our objective to investigate the effect of asymptomatic infection with HIV on the expression of lymphocyte activation markers after stimulation with mitogens. Whole blood cultures were made of HIV+ and HIV- subjects (29 asymptomatic HIV-1-infected subjects and 33 apparently healthy normal volunteers). At various times after stimulation with concanavalin A (Con A), anti-CD3 and pokeweed mitogen (PWM), the expression of activation markers (CD25 and HLA-DR) and the blastogenesis were quantified by flow cytometry. The flow cytometric quantification of the expression of activation markers and blastogenesis in whole blood cultures provided an easy and safe alternative to thymidine incorporation to assess lymphocyte responses in HIV+ subjects. Activation showed a tendency to be lower in the HIV+ subjects with all three stimulants. This difference with HIV- subjects was statistically significant only for stimulation with PWM after 4 days. Further investigations should be undertaken to show whether this functional impairment is related to disease progression and whether it can be influenced by effective therapy.