骨质疏松性骨折（OP骨折）是骨质疏松症的最严重并发症。OP骨折的早期预防和预警水平亟待提高。基于已建立的大型前瞻性骨质疏松症队列（1万人以上）,前期采用极端取样设计，选用GSH-CAA-440蛋白芯片（同时检测440个血浆蛋白），筛选到显著差异表达的CXCL13，进一步通过ELISA在扩大的极端样本中（40：40）验证了CXCL13的差异。本项目将首先在基线随机群体中验证CXCL13与骨质疏松的相关性。在前瞻性队列中，构建包括临床数据、跌倒风险、骨转换标志物等大规模数据的Cox预警模型；并作CXCL13作为生物标志物的临床应用评价，最后对CXCL13的功能进行深入研究,主要研究它是否影响成骨细胞的增值、分化、周期以及凋亡等。本项目将系统评价CXCL13是否可作为OP骨折的预警生物标志物，开发适合中国国情的OP骨折早期诊断预警方法，将有助于改善我国骨质疏松症的预防现状。

Osteoporotic fracture (OP fracture) is the most serious complication of osteoporosis. It is urgent to improve early prevention and early warning level of OP fracture. Based on the established large prospective cohort on osteoporosis (>10 thousand), By adopting the extreme sampling design, and by using GSH-CAA-440 protein chip (simultaneous detection of 440 serum protein), we found the significant difference of CXCL13, and confirmed the significant difference by using ELISA in another larger extreme sample (40:40). This project will first verify the correlation between CXCL13 and osteoporosis in the baseline random population. In a prospective cohort, Cox early warning model will be constructed by including clinical data, fall risk, bone turnover markers. The clinical application of CXCL13 will be evaluated as biomarker. In-depth studies for the CXCL13 function will test whether it affects osteoblast in proliferation, differentiation, apoptosis and cycle apoptosis. This project will systematically evaluate whether CXCL13 can be used as an early warning biomarker for OP fracture, and develop early diagnosis and early warning method for OP fracture suitable for China's national conditions, which will help to improve the current situation of osteoporosis prevention in China.