Figure 8.

Increased IL-21R expression correlates with increased SP1 binding to the IL-21R promoter in RA. (A) Total B cells were isolated from whole blood from RA patients and controls. SP1 binding to the IL21R promoter region and negative control IgG binding were determined using ChIP-qPCR analysis. The results are presented relative to input DNA. Significance was assessed using the student's t-test; n = 4 [Control (black circle), RA High (gray triangle)] n = 3 [RA Low (white square)]. ^**p < 0.01. (B) Correlation between IL-21R expression in total B cells as assessed by flow cytometry and SP1 relative binding to the IL21R gene as assessed by ChIP-qPCR and presented in A. One subject from the RA low cohort was excluded due to low purity of the B cell population. Significance was determined using Mann Whitney U tests (A) and Pearson correlations (B).