[Surface receptors on lymphocytes and blast cells developing from them after a 3-day culture stimulated with concanavalin A].

Surface receptors were studied by means of rosette tests E and EAC on lymphocytes cultured for 3 days without stimulation and in the presence of a mitogen--concavalin A. It was observed that lymphocytes cultured for 3 days maintained the ability or rosette E and EAC formation and a considerable proportion of these cells formed additionally rosettes E at 37 degrees without a close contact between the cells obtained during centrifugation and without incubation at 4 degrees C. Blast cells developing from lymphocytes after concavallin A possessed on their surface receptors for sheep erythrocytes and formed E rosettes under generally known conditions as well as after incubation at only 37 degrees C. EAC rosettes were found sporadically among transformed cells. Comparative investigations of cells forming rosettes E and EAC before culture and after 3 days of culture with concavalin A confirm the hypothesis that this mitogen stimulates to blastic transformation mainly T cells. The possibility of stimulation of lymphocytes not possessing receptors for sheep erythrocytes or for C3 component of complement is discussed.