MAP4K3/GLK-induced AhR-RORγt complex is a novel therapeutic target for GLKhighIL-17Ahigh subpopulation of SLE patients

Abstract

Abstract The cytokine IL-17A plays critical roles in the pathogenesis of autoimmune diseases. The frequencies of MAP4K3 (also named GLK)-overexpressing T cells are correlated with disease severity of systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and adult-onset Still’s disease. T-cell specific GLK transgenic mice develop spontaneous autoimmune responses. GLK signaling selectively stimulates IL-17A production in murine T cells through inducing AhR-RORγt complex formation. Here, we investigated whether GLK-induced AhR-RORγt complex in T cell is a therapeutic target for human SLE or RA. The population of GLK+IL-17A+ T cells was enhanced in the peripheral blood from SLE patients compared to that of healthy controls using flow cytometry. The ROC curve analyses showed that increased GLK+IL-17A+ T cell population in peripheral blood reflected an active stage of SLE. In addition, peripheral blood T cells from SLE or RA patients displayed induction of RORγt phosphorylation and the AhR-RORγt complex. Moreover, we identified a small-molecule GLK inhibitor that inhibited GLK kinase activity and AhR-RORγt interaction. The GLK inhibitor suppressed the disease severity in autoimmune mouse models and IL-17A production in T cells from SLE or RA patients. Collectively, GLK-induced AhR-RORγt complex is a therapeutic target for the GLKhighIL-17Ahigh subpopulation of SLE or RA patients.