The Yin and Yang of signaling in T_regs and T_H17 cells

Substantial advances in our understanding of the developmental and functional relationship between regulatory T cells (T_regs) and T helper 17 (T_H17) cells and their potential clinical applications have been made. In response to these break-throughs, the second international conference entitled "China Tregs/Th17 2010 Shanghai Conference," held in Shanghai, China, was dedicated to this topic. Various types of T _regs and T_H17 cells, as well as their relevant cytokines, were discussed. Here, we summarize some of the findings shared at the conference, specifically focusing on the biology of T_H17 cells, including interleukin-17 (IL-17)-producing innate cells, T_regs, and the factors that control the critical balance between T_regs and cells of the T_H17 lineage.