强直性脊柱炎外周血破骨细胞前体细胞活性的研究

Objective To investigate the number of osteoclast (OC) precursor in the peripheral blood of patients with ankylosing spondylitis (AS) and its relationship with serum receptor activator of nuclear factor KB-ligand (RANKL) and Osteoprotegerin (OPG) concentration as well as the disease activity. Methods The peripheral blood mononuclear cells from 8 cases of AS patients and 5 healthy controls were cultured in the medium containing macrophage colony-stimulating factor (M-CSF) (25 ng/ml) and RANKL (40 ng/ml). After being cultured for 14 days, cytochemistry was applied to detect tartrate-resistant acid phosphatase (TRAP) expression and the cells with TRAP expression and ≥3 nuclei were counted and defined as OC. Bone resorption assay was used to demonstrate OC function. ELISA was used to measure serum RANKL and OPG concentration in 23 cases of AS and 17 healthy controls. The relationship was analyzed in AS patients between the number of OC precursors and serum RANKL and OPG concentration as well as the disease activity. The indicators of disease activity were Bath ankylosing spondylitis disease activity index (BASDAI), Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). T test, t' test and Spearman correlation were selec-ted. Results ① Significantly higher OC production was observed in the peripheral blood of AS patients than that of healthy control group. The OC number per ten fields was 10.9±3.4 and 6.2±1.3 respectively (P<0.05); ② There was significant difference between AS patients and healthy controls in serum concentration of OPG and RANKL and the ratio of RANKL/OPG. OPG was significantly higher in AS patients [(157±49) pg/ml] than in healthy controls [(105±20) pg/ml] (P<0.05). RANKL was significantly higher in AS patients [(5.4± 3.8) pg/ml] than in healthy controls [(1.6±0.8) pg/ml] (P<0.05). The ratio of RANKL/OPG was significantly higher in AS patients (0.037±0.026) than in healthy controls (0.016±0.008) (P<0.01 );③Significantly positive correlation was observed between the OC number and the serum concentration of RANKL (r=0.692, P=0.009), the ratio of RANKL/OPG (r=0.813, P=0.001);④ In AS patients, serum concentration of OPG was found to have significantly negative correlation with BASDAI (r=-0.444, P=0.044). Serum RANKL concentration was found to have significantly positive correlation with BASDAI (r=0.543, P=0.011). The ratio of RANKL/OPG was found to have significantly positive correlation with BASDAI (r=0.672, P=0.001). Conclusion ① More OC precursors exist in the peripheral blood of AS patients. These cells may differentiate into osteoclasts, which might play a role in joints destructions in AS;② The mechanism of high OC production is likely to be due to high RANKL concentration which is caused by inflammatory reaction.

Osteoclast precursors in peripheral blood of patients with ankylosing spondylitis