ABSTRACT
BACKGROUND: AEB071, an orally available PKC inhibitor, prevents organ rejection after transplantation in rodents and man. Furthermore, pro-inflammatory cytokines and inflammatory processes are important mediators of transplanted organ rejection. We therefore examined whether single or combination therapies of AEB071 and/or tacrolimus affect cytokine profiles in a rat cardiac allograft model. METHODS: AEB071 (60 mg/kg twice a day) and tacrolimus (0.6 or 1.2 mg/kg once a day) were orally administered daily after cardiac transplantation. Interferon (IFN)-gamma, interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, and tumor necrosis factor (TNF)-alpha levels in serum were subsequently measured 5 days after cardiac transplantation using a multiplex protein assay system. RESULTS: All cytokine levels were significantly depressed in cardiac transplanted rats treated with AEB071, whereas tacrolimus only reduced IFN-gamma, IL-2, IL-4, IL-6, and IL-10 levels. When administered in combination, AEB071 and low- or high-dose tacrolimus had additive effects on IFN-gamma, IL-4, IL-6, and TNF-alpha. CONCLUSIONS: These results suggest that AEB071 inhibits T cell activation by blocking the production of proinflammatory cytokines, and that tacrolimus combined with AEB071 can effectively regulate inflammatory cytokines in the transplantation setting.