In vitro effects of cocaine on cytokine secretion induced in murine splenic CD4+ T cells by antigen-specific stimulation.

The in vitro effects of cocaine on antigen-specific-induced cytokine production by murine splenocytes was evaluated both by quantitation by ELISA of the cytokines in culture supernatants and by flow cytometric analysis of the frequency of the cytokine-producing CD4+ T cells. Spleen cells from mice immunized with ovalbumin (OVA) were restimulated with OVA in the presence or absence of cocaine for different periods of time and then evaluated for production of cytokines. Exposure to cocaine was found to reduce the levels in culture supernatants of IL2 and IFN-gamma, whereas IL4 and IL5 levels were not changed. Flow cytometric analysis showed that cocaine increased the frequency of IL2- but not of IL4-producing CD4+ T cells. Kinetics studies indicated that the in vitro antigen-specific-induced production of IL2 is faster than that of IL4 and that cocaine did not affect the production kinetics of either cytokine. Collectively, the results suggest that in vitro cocaine acts by interfering with the secretion rather than with the synthesis of cytokines and that the drug exerts different effects on cytokines with different production kinetics.