Siglec-5 is a novel marker of critical limb ischemia in patients with diabetes.

Critical Limb Ischemia (CLI) is common but uncommonly diagnosed. Improved recognition and early diagnostic markers for CLI are needed. Therefore, the aim of our study was to identify plasma biomarkers of CLI in patients with type 2 diabetes mellitus (T2DM). In this study, antibody-coated glass slide arrays were used to determine the plasma levels of 274 human cytokines in four matched cases of diabetes with and without CLI. Potential biomarkers were confirmed in an independent cohort by ELISA. After adjusting for confounding risk factors, only plasma level of Siglec-5 remained significantly associated with an increased odds ratio (OR) for diabetes with CLI by binary logistic regression analysis. Receiver operating characteristic (ROC) curve analysis revealed the optimal cut-off points for Siglec-5 was 153.1 ng/ml. After entering Siglec-5, the AUC was 0.99, which was higher than that of confounding risk factors only (AUC = 0.97, P < 0.05). Siglec-5 was expressed in plaques, but not in healthy artery wall in T2DM patients. Elevated plasma Siglec-5 was independently associated with CLI in T2DM. Plasma Siglec-5 levels are implicated as an early diagnostic marker of CLI in T2DM patients and it may become a target for the prevention or treatment of CLI in diabetes.

严重肢体缺血（CLI）常见，但诊断率不高。需要提高对CLI的认识以及找到早期诊断标志物。因此，我们研究的目的是确定2型糖尿病（T2DM）患者中CLI的血浆生物标志物。在这项研究中，使用抗体包被的玻片阵列来测定4对患有和未患有CLI的糖尿病患者中274种人类细胞因子的血浆水平。通过酶联免疫吸附测定（ELISA）在一个独立队列中对潜在的生物标志物进行了确认。在对混杂风险因素进行调整后，通过二元逻辑回归分析，只有Siglec - 5的血浆水平与伴有CLI的糖尿病的优势比（OR）增加仍显著相关。受试者工作特征（ROC）曲线分析显示Siglec - 5的最佳截断值为153.1 ng/ml。纳入Siglec - 5后，曲线下面积（AUC）为0.99，高于仅考虑混杂风险因素时的AUC（AUC = 0.97，P < 0.05）。在T2DM患者中，Siglec - 5在斑块中表达，但在健康动脉壁中不表达。血浆Siglec - 5升高与T2DM中的CLI独立相关。血浆Siglec - 5水平被认为是T2DM患者CLI的早期诊断标志物，它可能成为糖尿病中CLI预防或治疗的靶点。