Effects of leflunomide on the spectrum of inflammatory cytokines secreted by the peripheral blood mononuclear cells in patients with lupus nephritis

Objective To investigate the effects of leflunomide on the levels of IL-12, IFN-γ, IL-4, and IL-6 secreted by the peripheral blood mononuclear cells (PBMCs) in patients with lupus nephritis (LN). Methods PBMCs separated from both moderate or severe active LN patients (n = 10, female) and healthy controls (n = 9, female) were cultured with blank, phytohaemagglutinin (PHA) and/or leflunomide active metablite (A771726). ELISA method was utilized to measure the levels of IFN-γ, IL-12, IL-4, and IL-6 in the supernatants of cultured PBMCs from LN patients. Results Whether treated with PHA or not, the levels of IL-12, IFN-γ, IL-4, and IL-6 were all significantly elevated in the supernatants of cultured PBMCs from LN patients, as compared with healthy controls. And the levels of IFN-γ,IL-12, and IL-6 secreted by PBMCs from LN patients was significantly reduced by A771726, while the level of IL-4 was not significantly changed, as compared with PBMCs from LN patients hadn′t treated with A771726. Conclusions It may be another important mechanism to effectively treat LN that leflunomide can significantly down-regulate the productions of IL-12, IFN-γ and IL-6 by PBMCs from moderate or severe active LN patients.