ACP5 and psoriatic arthritis: Furthermore, the propensity to form TRAP+ MNGs demonstrated in this study was not inhibited by immunosuppressive treatment despite good control of disease (as indicated by the low BVAS-WG scores seen in this cohort) as opposed to psoriatic arthritis where osteoclast precursors drop rapidly following treatment with anti-tumor necrosis factor (TNF) agents [17].