text: IL-10 Production by Th2 and Th17 Cells Also Requires ERK1 and ERK2 Activation
  To address whether IL-10 production by Th2 and Th17 cells was also dependent on ERK1 and ERK2 activation, we differentiated these cells with anti-CD3 and anti-CD28 in the absence of APCs (Shoemaker etal., 2006; Veldhoen etal., 2009; Veldhoen etal., 2006), in the presence or absence of the MEK inhibitor (PD184352). We showed that ERK1 and ERK2 activation is a common pathway required for induction of IL-10 in different Th cell subsets because IL-10 production by both Th2 and Th17 cells was markedly inhibited in the presence of the MEK inhibitor (PD184352) (Figure5D and FigureS5B). In contrast, inhibitors of p38 MAPK or of GSK-3beta activation did not affect the expression of IL-10 by these subsets (FigureS5B). Activation of the ERK1 and ERK2 signaling pathway is therefore a common requirement for the induction of IL-10 production by Th1, Th2, and Th17 cells. 
  