IL17A and psoriatic arthritis: IL-17A gene could induce the proliferation of IL-17RA+CD11b+Gr1low osteoclast precursors, and the biomarkers of bone resorption also increased by transferring the IL-17A gene into the CIA model, which indicated that IL-17A could induce pathological bone resorption (a crux feature of psoriatic arthritis) through direct activation of osteoclast precursors (Marinoni et al., 2014; Adamopoulos et al., 2015; Sakkas and Bogdanos, 2017).