The yin and yang of signaling in Tregs and TH17 cells.

Substantial advances in our understanding of the developmental and functional relationship between regulatory T cells (T(regs)) and T helper 17 (T(H)17) cells and their potential clinical applications have been made. In response to these breakthroughs, 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(H)17 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(H)17 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(H)17 lineage.