Another fork in the road: Foxo3a regulates NF-kappaB activation.

Previous studies have implicated the transcription factor FoxO3a in apoptosis induction. Thus, it comes as a surprise in this issue of Immunity that lymphoproliferative disease in Foxo3a-deficient mice may be due to T cell hyperactivity instead of cell death defects. Lin and colleagues provide important new evidence that disease development is associated with NF-kappaB hyperactivation in T cells.