炎性重度肢体缺血（AICLI）多累及青壮年，致残率高，我国较西方国家高发，现有治疗效果差。课题组于国际上首次报道了干细胞移植治疗AICLI的5年期疗效，将截肢率和劳动力丧失率分别由31%和34.8%降至11.1%和24.7%。面临的瓶颈是：复发／再发率15%；无效率10%。针对性的攻克途径是：预判炎症活动；寻及上调移植后血管新生的靶点。LRG1在炎症活动判断和促血管生成中的作用与此吻合。本项目将国内外首次阐明：（1）AICLI中LRG1表达水平与疾病诊断及活动度的相关性和特点；（2）LRG1在干细胞移植治疗AICLI中促血管生成的作用及机制；（3）以LRG1作为靶点，上调治疗性血管生成的可行性和有效性。旨在：（1）为AICLI提供新的、更敏感的诊断及活动程度判断的血清标志物；（2）为进一步提高干细胞移植治疗AICLI的疗效寻求到新的靶点。从而为后续临床推进、让更多患者获益奠定基础。

Angiitis-induced critical limb ischemia (AICLI) usually develops in the young population, causing a high risk of amputation. Compared with western countries, the incidence of AICLI appears higher in China. The efficacy of conventional treatment remains rather unsatisfactory for AICLI. We have reported the promising 5-year outcomes of stem cells transplantation in AICLI, to our knowledge, for the first time in the world. The major amputation rates and labor loss rates were reduced from 31% and 34.8% to 11.1% and 24.7% respectively. The issues pending improvement were the recurrence rate of 15% and the inefficacy rate of 10%. A planned solution is to find a potential factor which could both predict inflammatory activity and up-regulate the angiogenesis. The significant role of LRG1 in the judgment of inflammatory activity and the promotion of angiogenesis is consistent with this. Hence, this project will clarify following aspects for the first time in the world: (1) the characteristics and correlation of LRG1 expression level in AICLI with disease diagnosis and inflammatory activity; (2) the role and mechanism of LRG1 in promoting angiogenesis in stem cells transplantation for AICLI; (3) the feasibility and efficacy of LRG1 as a target to upregulate therapeutic angiogenesis. The purpose of this study is to: (1) provide a new and more sensitive serum marker for AICLI diagnosis and activity judgment; (2) find a new target for further improving the efficacy of stem cells transplantation in the treatment of AICLI. This study will lay the foundation for improving the clinical treatment for AICLI to benefit more patients in the future.