Helper T cell differentiation enters a new era: Le Roi est mort; vive le Roi!

摘要

In the dark ages of T cell biology, we considered two fates for differentiated CD4⁺ T cells: T helper (Th)1 and Th2 cells. Now we know that the reality is much more complex and interesting. The newest Th cell subset produces the cytokine IL-17. New evidence shows that the IL-17–related cytokine IL-25 is essential for Th2 responses in two infectious disease models.