TCF-1 at the Tfh and Th1 Divergence

Three recent studies provide new insight into the mechanisms that promote the differentiation of antigen-primed T cells into the follicular helper T (Tfh) lineage, revealing a key role for the transcription factor TCF-1 in the regulation of the Bc16-Blimp-1 axis that mediates the divergence between the Tfh and the TM lineages.