Department of Gastroenterology, Infectiology and Rheumatology, Charité Berlin, Campus Benjamin Franklin, Berlin, Germany.
J Rheumatol. 2010 Apr;37(4):823-8. doi: 10.3899/jrheum.090986. Epub 2010 Feb 15.
New bone formation of the spine is a typical feature of ankylosing spondylitis (AS). It is unknown whether new bone formation is part of a physiological repair process or a unique pathological entity of the disease.
We analyzed zygapophyseal joints from patients with AS and osteoarthritis (OA) undergoing spinal surgery for rigid hyperkyphosis (AS) or radiculopathy caused by severe OA. In 17 patients with AS, 11 with OA, and 5 controls we performed immunohistochemical analysis of osteoprotegerin (OPG), nuclear factor-kappaB ligand (RANKL), and osteocalcin (OC) expression in osteoblasts and determined the trabecular thickness in AS and OA patients and controls. Osteoclasts were detected by tartrate-resistant alkaline phosphatase (TRAP) staining.
Trabecular thickness was significantly lower in patients with AS compared to OA (p = 0.01). The absolute number of CD56+ osteoblasts (p < 0.001) and OC+ (p = 0.002), OPG+ (p = 0.003), and RANKL+ osteoblasts (p = 0.03) in AS patients was also significantly lower than in OA patients. The percentages of OC+, OPG+, and RANKL+ osteoblasts did not differ between AS and OA (p > 0.05 in all cases). In controls, the percentages of OPG+ (p = 0.013) and OC+ (p = 0.034) but not RANKL+ (p > 0.05) osteoblasts were significantly lower compared to AS patients. The frequency of TRAP+ osteoclasts in AS patients was significantly lower compared to OA (p < 0.001), but higher compared to controls.
Immunohistochemical analysis of zygapophyseal joints suggested that osteoblast activity is similar in AS and OA, indicating that new bone formation is possibly a physiological function of repair in both diseases.
脊柱新骨形成是强直性脊柱炎（AS）的典型特征。目前尚不清楚新骨形成是生理修复过程的一部分，还是疾病的独特病理实体。
我们分析了因僵硬性脊柱后凸（AS）或严重 OA 引起的根性病变而行脊柱手术的 AS 和骨关节炎（OA）患者的椎间关节。在 17 例 AS 患者、11 例 OA 患者和 5 例对照者中，我们对成骨细胞中的骨保护素（OPG）、核因子-κB 配体（RANKL）和骨钙素（OC）表达进行了免疫组织化学分析，并确定了 AS 和 OA 患者和对照者的小梁厚度。通过抗酒石酸酸性磷酸酶（TRAP）染色检测破骨细胞。
与 OA 患者相比，AS 患者的小梁厚度明显较低（p=0.01）。AS 患者的 CD56+成骨细胞（p<0.001）和 OC+（p=0.002）、OPG+（p=0.003）和 RANKL+成骨细胞的绝对数量也明显低于 OA 患者。AS 和 OA 患者的 OC+、OPG+和 RANKL+成骨细胞的百分比无差异（p>0.05）。在对照组中，与 AS 患者相比，OPG+（p=0.013）和 OC+（p=0.034）但不是 RANKL+（p>0.05）成骨细胞的百分比明显较低。与 OA 患者相比，AS 患者的 TRAP+破骨细胞频率明显较低（p<0.001），但高于对照组。
椎间关节的免疫组织化学分析表明，AS 和 OA 中的成骨细胞活性相似，表明新骨形成可能是两种疾病修复的生理功能。
