人脐带间充质干细胞重复静脉注射动物毒性试验

摘要 目的：评价多次尾静脉注射脐带间充质干细胞（hUC-MSCs）对小鼠的体内毒性作用。方法：48只健康ICR小鼠，按性别和体重随机分为4组（即对照组、低剂量组、中剂量组和高剂量组）。小鼠通过微静脉注射不同剂量hUC-MSCs悬浮液，间隔3天给药1次，共给药4次。记录小鼠摄食量、体重、体温，给药结束后恢复两周后牺牲动物作大体解剖，检查各个器官器质性病变；利用流式细胞仪分别检测CD3、CD4、CD8阳性细胞亚群数量；ELISA试剂盒检测血清IgM、IgG、C3、C4指标；对肺脏、脾脏、肾脏行组织病理学检查。结果：实验组与对照组相比较，注射不同剂量干细胞后一般观察、体重、体温、摄食量、IgM以及C3在给药期和恢复期均未发生显著变化。在恢复期，注射中、高剂量hUC-MSCs组血清IgG和C4水平略有降低，但未达到显著水平P<0.05；CD4阳性T细胞集群数量以及CD4/CD8系数在hUC-MSCs中、高剂量组显著上升（P<0.05）。大体剖检，除脾脏相比溶媒对照组略显增大外其它各器官均未发现肉眼可见明显异常；称重后发现hUC-MSCs高剂量组脾重量与溶媒对照组相比显著升高（P<0.05）。脾脏、肺脏、肾脏病理学检测未见明显异常。结论：健康ICR小鼠尾静脉注射临床剂量hUC-MSCs（1×10⁶ cells/kg）可能调动动物免疫反应，此外，未观察到hUC-MSCs对小鼠有明显毒副作用。

Toxicity Test of Repeated Intravenous Injection of Human Umbilical Cord Mesenchymal Stem Cells in Mice

ABSTRACT Objective: To evaluate the in vivo toxicity of multiple tail vein injection of human umbilical cord mesenchymal stem cells (hUC-MSCs) in mice. Methods: 48 healthy ICR mice were randomly divided into 4 groups (control, low dose, medium dose and high dose) according to gender and body weight. Mice were injected with different doses of hUC-MSCs suspension through micro vein, once every 3 days, for a total of 4 times. The food intake, body weight and body temperature of mice were recorded The mice were sacrificed after 2 weeks of recovery after administration, the animals were dissected and the organic lesions of various organs were examined; The number of CD3, CD4 and CD8 positive cell subsets was detected by flow cytometry; Serum IgM, IgG, C3 and C4 were detected by ELISA kit; The lung, spleen and kidney were examined by histopathology. Results: Compared with that in the control group, there were no significant changes in general observation, body weight, body temperature, food intake, IgM and C3 during administration and recovery after injection of different doses of stem cells. In the recovery period, the levels of serum IgG and C4 in the middle and high-dose hUC-MSCs groups decreased slightly, but they did not reach a significant level (P<0.05); The number of CD4 positive T cell clusters and CD4 / CD8 coefficient increased significantly in hUC-MSCs medium and high dose groups(P<0.05). No obvious abnormality was found in other organs except that the spleen was slightly larger than that in the control group; The spleen weight of hUC-MSCs high-dose group was significantly higher than that in control group (P<0.05). No obvious abnormality was found in the pathological examination of spleen, lung and kidney. Conclusion: Healthy ICR mice injected with clinical dose HUC MSCs (1×10⁶ cells / kg) may mobilize animal immune response. However, no obvious toxic and side effects of hUC-MSCs on mice were observed.