TNFRSF25 and Arthritis: F4/80+ macrophage staining was significantly (P < 0.05) increased in mild disease when compared to nonimmunized controls (8.8 ± 2.4%, n = 15 vs. 3.1 ± 0.6%, n = 8) and this was again mirrored by significantly (P < 0.05) increased DR3 expression in mild arthritis (10.2 ± 2.5%, n = 14 vs. 5.8 ± 0.8%, n = 8).