In vitro monocyte-lymphocyte interaction influenced by d-penicillamine.

The in vitro effect of d-penicillamine (Pen) on human peripheral blood mononuclear cells (PBMC) was studied in relation to pokeweed mitogen (PWM) stimulation. Incubation of PBMC with Pen during or after PWM stimulation resulted in only a slight decrease in blast-cell formation. This effect was dependent on the concentration of Pen. Preincubation of PBMC with 100 micrograms Pen/ml medium for 10 days led to a toxic effect on lymphoid cells and selective survival of mononuclear phagocytes (MNP). Preincubation with 10 and 50 micrograms Pen/ml medium resulted in limited spontaneous blast-cell formation, which did not occur after preincubation with 100 micrograms Pen/ml and 5 micrograms Pen/ml. Despite the decrease in the total number of lymphocytes after 10 days of Pen preincubation, blast-cell formation on subsequent PWM stimulation in the absence of Pen was considerably enhanced compared to controls. The blast-cell formation was suppressed when PWM stimulation of Pen-preincubated PBMC was performed in the presence of Pen. This suppression of blast-cell formation under stimulation in the presence of Pen might explain the therapeutic effect of Pen.