HIV aliquots, from a supernatant of ARV-4 cell line, were mixed with an equal volume of a OSCN.generating glucose-glucose oxidase + thiocyanate-lacteroperoxidase solution, and then pre-incubated at 37 degrees C for periods of 30 secs to one hour. These mixtures were then inoculated into cultures of phytohaemagglutinin-stimulated lymphocytes. Viral growth was monitored with an ELISA quantitating the specific p24 protein either in the culture cells or in the supernatant. In control experiments, the virus produced both intra- and extra-cellular p24. In the controls, concentration of p24 per 10(6) lymphocytes grew rapidly. By contrast, HIV that was pretreated with the OSCN generating system for 30 sec., produced very little p24, and no detectable amount of this protein could be found after 2 min. pre-treatment.