The Transcription Factors Egr2 and Egr3 Are Essential for the Control of Inflammation and Antigen-Induced Proliferation of B and T Cells

Lymphocytes provide optimal responses against pathogens with minimal inflammatory pathology. However, the intrinsic mechanisms regulating these responses are unknown. Here, we report that deletion of both transcription factors Egr2 and Egr3 in lymphocytes resulted in a lethal autoimmune syndrome with excessive serum proinflammatory cytokines but also impaired antigen receptor-induced proliferation of B and T cells. Egr2- and Egr3-defective B and T cells had hyperactive signal transducer and activator of transcription-1 (STAT1) and STAT3 while antigen receptor-induced activation of transcription factor AP-1 was severely impaired. We discovered that Egr2 and/or Egr3 directly induced expression of suppressor of cytokine signaling-1 (SOCS1) and SOCS3, inhibitors of STAT1 and STAT3, and also blocked the function of Batf, an AP-1 inhibitor, in B and T cells. Thus, Egr2 and Egr3 regulate B and T cell function in adaptive immune responses and homeostasis by promoting antigen receptor signaling and controlling inflammation. º Deletion of Egr2 and Egr3 in lymphocytes results in a lethal autoimmune syndrome º Deficiency in both Egr2 and Egr3 impairs antigen receptor-induced proliferation º Egr2 and Egr3 are required for AP-1 activity by blocking Batf º Egr2 and Egr3 induce expression of SOCS1 and SOCS3