Understanding the developmental mechanisms of follicular helper T cells (T FH cells) in humans is relevant to the clinic. However, the factors that drive the differentiation of human CD4 + helper T cells into T FH cells remain largely undefined. Here we found that transforming growth factor-β 2 (TGF-β 2) provided critical additional signals for the transcription factors STAT3 and STAT4 to promote initial T FH differentiation in humans. This mechanism did not appear to be shared by mouse helper T cells. Developing human T FH cells that expressed the transcriptional repressor Bcl-6 also expressed RORγ 3t, a transcription factor typically expressed by the T H 17 subset of helper T cells. Our study documents a mechanism by which T FH cells and T H 17 cells emerge together in inflammatory environments in humans, as is often observed in many human autoimmune diseases.
ASJC Scopus subject areas
- Immunology and Allergy