Figure 4.

CRP-induced IL-23 production is only partially dependent on Syk signaling. Human monocytes were stimulated with 25 µg/mL CRP. FcR signaling was blocked prior to stimulation by treatment with a mixture of specific antibodies against FcγRI, FcγRII, FcγRIII, and FcαRI (A) or by addition of Syk kinase inhibitor R406 [0.5 µM] (B,C). After 24 h, IL-23 and TNF production was determined by ELISA. Representative example of one donor of four experiments using four different donors (A) or pooled data of eight (B,C) donors. Every pair of dots represents the cytokine induction by one donor, average value indicated by dotted line. * p < 0.05, *** p < 0.001, paired t-test.