Basophils induce Th2 immunity

Abstract

Despite the fact that basophils represent less than 0.5% of circulat- ing leukocytes, recent studies have begun to unveil their potent immunoregulatory functions, i.e., induction of Th2 immunity. It is believed that basophils are capa- ble of doing so primarily by secreting key Th2-inducing cytokines, namely IL-4 and Thymic Stromal Lymphopoietin (TSLP), and by functioning as profes- sional antigen presenting cells. However, we have recently demonstrated that Th2 immunity can develop in the absence of basophils or IL-4 during helminth infec- tion. In this review, how basophils may (and may not) contribute to the development of Th2 immunity in vivo is discussed.