Change of serum interleukin-23 levels and sacroiliac joint magnetic resonance imaging before and after treatment with recombinant human tumor necrosis factor-α receptor II IgG Fc fusion protein for injection in axial spondyloarthritis patients

Abstract

Objective We investigated interleukin (IL)-23 that might play a role in the pathogenesis of rheumatoid arthritis (RA) and whether it was correlated with disease activity and clinical manifestations in axial spondyloarthritis(SpA). In addition, the Spondyloarthritis Research Consortium of Canada (SPARCC) scores was used to examine whether recombinant human tumor necrosis factor-α receptor Ⅱ IgG Fc fusion protein for injection (rhTNFR: Fc) was effective for the reduction of magnetic resonance imaging (MRI)-proven sacroiliac joint (SIJ) inflammation. Methods The serum IL-23 levels of etanercept and conven-tional treatment groups were measured using enzyme-linked immunosorbent assay kits. At the same time, SIJ MRI SPARCC score levels were assessed by MRI, the change of clinical indicators of patients was observed. ANOVA, repeated measure data of ANOVA and Spearman's correlation analysis were used for statisical analysis. Results ① The basal serum IL-23 levels of the Etanercept group were (34.2±1.8) pg/ml and those of the conventional treatment group were (34.1±1.8) pg/ml (F=1 073.790, P=0.991) , both were significantly higher than the healthy control group (18.1±0.8) pg/ml (P=0.005). After treatment, serum IL-23 levels of the rhTNFR: Fc treatment and conventional treatment group were (24.5±1.7) pg/ml and (25.2±1.7) pg/ml (F=232.488, P=0.242) , (19.2±0.8) pg/ml and (21.6±1.3) pg/ml (F=114.135, P=0.025) , (19.0±0.8) pg/ml and (19.4±0.8) pg/ml (F=23.374, P=0.085) respectively. A significant decrease was observed in the two groups and the serum level of IL-23 of the rhTNFR: Fc group was lower than that of the conventional group at week 12. ② SIJ MRI SPARCC scores of the rhTNFR: Fc group and the conventional drugs group were (20.1± 1.2) scores and (20.7±1.5) scores (F=2003.660, P=0.191) , (12.5±0.8) scores and (15.4±0.9) scores (F=1 680.430, P=0.004) , (8.8±0.9) scores and (12.8± 0.9) scores (F=972.877, P=0.002) , the scores of two group were significantly decreased after treatment. At week 12, 24 of the treatment, the rhTNFR: Fc group scores were lower than the conventional drugs group. ③ The serum IL-23 levels, SIJ MRI SPARCC scores and clinical index (ESR, CRP, PGA, BASDAI, BASFI, BASMI and number of painful joints) were not correlated (P>0.05), the SIJ MRI SPARCC scores and clinical indicators were not correlated (P>0.05). Conclusion ① The serum IL-23 levels of the rhTNFR: Fc are higher than healthy controls. ② rhTNFR: Fc treatment could significantly decrease IL-23 levels and improve the sacroiliac joint inflammation compared to conventional treatment. ③ SIJ MRI is a good assessment method for the detection of SpA sacroiliac joint inflammation. Key words: Arthritis; Interleukins; Sacroiliac joints; Magnetic resonance imaging