Clinical research of interleukin-34 in psoriatic arthritis patients / 中华风湿病学杂志

ABSTRACT

Objective To investigate the relationship between interleukin (IL)-34 and bone erosions in psoriatic arthritis (PsA) patients.Methods Forty PsA patients,20 psoriasis (Ps) patients and 20 healthy volunteers were recruited into this study.The levels of IL-34 and osteoclast related cytokines [including tumor necrosis factor (TNF)-α,receptor activator of nuclear factor-κB ligand (RANKL),osteoclast precursors (OPG)] were detected in the serum samples of all subjects.The correlations among IL-34,the number of osteoclast precursors (OCP),disease activity and imaging scores were analyzed.All data were analyzed by graphpad prism 6.Differences between groups was analyzed with One-way analysis of variance,q tests,and Spearman's correlation was used to explore the relation between disease activity/radiographic scores and laboratory results and followed by linear regressions.Results The serum level of IL-34 in patients with PsA [(328±476) pg/ml] was higher than that in Ps [(33±52) pg/ml,q =3.92,P＜0.01] and healthy controls [(32±32) pg/ml,q =3.93,P＜0.01],the erosive PsA group were higher than the non-erosive PsA group [(449±527) pg/ml and (47±24) pg/ml,q=4.04,P＜0.01].The levels of TNF-α,RANKL and OCP in patients with PsA [(125±79) pg/ml,(488± 475) pg/ml and (17.7±4.8) 5 sigh views] were higher than those in PS [(40±22) pg/ml,(26±3) pg/ml and (5.2± 0.8),q=7.32,6.14 and 2.94,P＜0.01] and healthy controls [(41±19) pg/ml,(65±8) pg/ml and (6.2±1.8),q=6.67,5.62 and 2.71,P＜0.01],whereas the OPG/RANKL ratio in PsA patients (0.5±0.4) was significantly lower than Ps patients (4.3±2.7,q=-3.30,P＜0.01) and healthy controls (1.8±0.6,q=-1.72,P＜0.01).IL-34,TNF-α and RANKL levels were all positively correlated with OCP (r=0.10,P＜0.05;r=0.12,P＜0.05;r=0.13,P＜0.(5,respectively).Conclusion The level of IL-34 is not only high in patients with PsA but also positively correlates with the number of OCP.In PsA,IL-34 is probably related to the OCP and osteoclast differentiation,and further participates in the process of bone destruction.Therefore,IL-34 is promising to become a new target or alternative choice for the treatment of PsA.