SELP and rheumatoid arthritis: RA significantly increased levels of P-selectin (55.5 ± 26.1 vs. 68.9 ± 26.5, p < 0.001), CD40L (2261.3 ± 2489.9 vs. 3602.0 ± 2428.5, p = 0.01), and PF4 (6054.7 ± 5751.8 vs. 10,877.6 ± 4979.7, p < 0.001).