Enhanced PYK2 phosphorylation in PBMCs in response to lymphocyte activation stimulated by PMA. (A) PBMCs obtained from healthy donors (n = 24), RA patients (n = 32) and SLE patients (n = 48) were incubated in 24-well culture dishes in 5% CO2 at 37°C for 24 h for with no stimulation (medium), or stimulation with PMA (1 ng/ml). Lysates prepared from 2 × 106 cells were analyzed by western blotting for the expression of p-PYK2 as indicated in patients and methods. (B) p-PYK2 expressed relative to the value obtained with PMA stimulation. Bars represent the mean and standard deviation of three separate experiments. Statistical analysis: * = p < 0.05.