Effects of ribavirin on cytokine production of recall antigens and phytohemaglutinin-stimulated peripheral blood mononuclear cells. (Inhibitory effects of ribavirin on cytokine production)

Aim: To evaluate the effects of ribavirin on cytokine production of recall antigen and PHA-stimulated PBMC obtained from healthy individuals. Materials and methods: PBMC were challenged with tetanus toxoid (5μg/mL) and PHA (10 μmL) in absence or presence of ribavirin at different concentrations (1, 10 and 100 (μM). Parallel sets of wells containing PBMC exposed to medium alone were used as negative controls. On day 3 after initiation of the cultures, IL-2, IFN-γ, IL-4, IL-10, TNF-α content were determined in supernatants of PBMC from the different individuals. Results: The effects of ribavirin on cytokine released by human PBMC in response to PHA and TT showed a great variation among individuals. No significant changes were observed between 1-10μ M concentrations in the production of TNF-α, IFN-γ and IL-10 by both PHA and TT-stimulated PBMC. Ribavirin inhibited TNF-α, IFN-γ, and IL-10 in both PHA and TT-stimulated PBMC at 100 μM (p <0.05). At this concentration, ribavirin induced an increase of 124% in the production of IL-2 by PHA-stimulated PBMC (p <0.05). Conclusions: The present data suggest that ribavirin may cause diverse effects on immunoregulatory cytokine secretion with changes in the Th1/Th2 balance.