Koga T, Hedrich CM, Mizui M, Yoshida N, Otomo K, Lieberman LA, Rauen T, Crispín JC, Tsokos GC. CaMK4-dependent activation of AKT/mTOR and CREM-α underlies autoimmunity-associated Th17 imbalance.
J Clin Invest 2014;
124:2234-45. [PMID:
24667640 DOI:
10.1172/jci73411]
[Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 01/23/2014] [Indexed: 12/17/2022] Open
Abstract
Tissue inflammation in several autoimmune diseases, including SLE and MS, has been linked to an imbalance of IL-17-producing Th (Th17) cells and Tregs; however, the factors that promote Th17-driven autoimmunity are unclear. Here, we present evidence that the calcium/calmodulin-dependent protein kinase IV (CaMK4) is increased and required during Th17 cell differentiation. Isolation of naive T cells from a murine model of lupus revealed increased levels of CaMK4 following stimulation with Th17-inducing cytokines but not following Treg, Th1, or Th2 induction. Furthermore, naive T cells from mice lacking CaMK4 did not produce IL-17. Genetic or pharmacologic inhibition of CaMK4 decreased the frequency of IL-17-producing T cells and ameliorated EAE and lupus-like disease in murine models. Inhibition of CaMK4 reduced Il17 transcription through decreased activation of the cAMP response element modulator α (CREM-α) and reduced activation of the AKT/mTOR pathway, which is known to enhance Th17 differentiation. Importantly, silencing CaMK4 in T cells from patients with SLE and healthy individuals inhibited Th17 differentiation through reduction of IL17A and IL17F mRNA. Collectively, our results suggest that CaMK4 inhibition has potential as a therapeutic strategy for Th17-driven autoimmune diseases.
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