CD4+ T cells that selectively produce interleukin (IL)-17 (TH17 cells) are essential for host defence and autoimmunity. It has been thought that IL-6 and transforming growth factor (TGF)-β1 are the factors responsible for initiating the specification of TH17 cells. Here, however, it is shown that TH17 differentiation can occur in the absence of TGF-β signalling. IL-6, IL-23 and IL-1β effectively induced IL-17 production in naive precursors. These data reveal an alternative mode for TH17 differentiation and the importance of IL-23.
- Kamran Ghoreschi
- Arian Laurence
- John J. O’Shea
