进行中的胰岛β细胞功能障碍是2型糖尿病（T2DM）患病机制的根本方面。最近，由于能够促进胰岛β细胞再生，间充质干细胞（MSC）移植作为一种新的治疗方法逐渐兴起。然而，目前的研究主要集中在其疗效上，对其安全性的临床研究较少。为评估人类脐带间质干细胞（hUC-MSC）输注治疗T2DM的安全性，我们设计了一项开放标签和随机分组的2期临床试验来评估hUC-MSC移植治疗T2DM的安全性。在A级医院，十名安慰剂组的患者每周一次静脉输注无细胞生理盐水，共连续3周。24名hUC-MSC组的患者每周一次静脉输注hUC-MSC（1 × 106个细胞/公斤），共连续3周。糖尿病的临床症状、体征、实验室检查和影像学结果在治疗后的第1个月每周进行评估，然后在第12周和第24周进行评估。在24周的随访期内未观察到严重的不良事件。hUC-MSC组中有4名患者（16.7％）出现短暂发热，发生在第二次或第三次输注后的24小时内，安慰剂组中没有患者出现这种情况。hUC-MSC组的1名患者在移植后1个月内发生低血糖发作。与安慰剂组相比，hUC-MSC组在第2周和第3周观察到明显较低的淋巴细胞水平和凝血酶凝结时间（P < 0.05）。与安慰剂组相比，hUC-MSC组在第3周观察到明显较高的血小板水平、免疫球蛋白水平（第1、2、3和4周）、纤维蛋白原水平（第2和第3周）、D-二聚体水平（第1、2、3、4、12和24周）和中性粒细胞/淋巴细胞比率（第2和第3周）（所有P < 0.05）。两组间在肿瘤标记物（α-核糖核酸、胚胎抗原和糖类抗原199）或血脂方面没有显著差异。在胸部X光片上未观察到肝损伤或其他副作用。我们的研究表明，在T2DM治疗中，hUC-MSC移植具有良好的耐受性和高度的安全性。它可以改善人体免疫功能并抑制淋巴细胞。鉴于这些结果，我们应密切监测凝血功能异常。©2023作者。百世登出版集团有限公司发表，保留所有权利。

Progressive pancreatic β cell dysfunction is a fundamental aspect of the pathology underlying type 2 diabetes mellitus (T2DM). Recently, mesenchymal stem cell (MSC) transplantation has emerged as a new therapeutic method due to its ability to promote the regeneration of pancreatic β cells. However, current studies have focused on its efficacy, and there are few clinical studies on its safety.To evaluate the safety of human umbilical cord (hUC)-MSC infusion in T2DM treatment.An open-label and randomized phase 2 clinical trial was designed to evaluate the safety of hUC-MSC transplantation in T2DM in a Class A hospital. Ten patients in the placebo group received acellular saline intravenously once per week for 3 wk. Twenty-four patients in the hUC-MSC group received hUC-MSCs (1 × 106 cells/kg) intravenously once per week for 3 wk. Diabetic clinical symptoms and signs, laboratory findings, and imaging findings were evaluated weekly for the 1st mo and then at weeks 12 and 24 post-treatment.No serious adverse events were observed during the 24-wk follow-up. Four patients (16.7%) in the hUC-MSC group experienced transient fever, which occurred within 24 h after the second or third infusion; this did not occur in any patients in the placebo group. One patient from the hUC-MSC group experienced hypoglycemic attacks within 1 mo after transplantation. Significantly lower lymphocyte levels (weeks 2 and 3) and thrombin coagulation time (week 2) were observed in the hUC-MSC group compared to those in the placebo group (all P < 0.05). Significantly higher platelet levels (week 3), immunoglobulin levels (weeks 1, 2, 3, and 4), fibrinogen levels (weeks 2 and 3), D-dimer levels (weeks 1, 2, 3, 4, 12, and 24), and neutrophil-to-lymphocyte ratios (weeks 2 and 3) were observed in the hUC-MSC group compared to those in the placebo group (all P < 0.05). There were no significant differences between the two groups for tumor markers (alpha-fetoprotein, carcinoembryonic antigen, and carbohydrate antigen 199) or blood fat. No liver damage or other side effects were observed on chest X-ray.Our study suggested that hUC-MSC transplantation has good tolerance and high safety in the treatment of T2DM. It can improve human immunity and inhibit lymphocytes. Coagulation function should be monitored vigilantly for abnormalities.©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.