摘　要：干细胞治疗作为某些难治性疾病的新型治疗手段，在组织修复、自身免疫疾病和退行性疾病治疗中具有重要的临床价值。本研究以裸鼠为动物模型，通过裸鼠皮下成瘤、克隆形成和端粒酶活性等试验，评估人脐带间充质干细胞的安全性，为干细胞用于临床治疗的安全性提供参考。裸鼠成瘤性试验结果显示，阴性对照组和试验组成瘤数均为0，阳性对照组成瘤数为12。克隆形成试验结果显示，阴性对照组和试验组无克隆形成，阳性对照组有克隆形成。端粒酶活性测定结果显示，阴性对照组端粒酶相对活性为0.01，阳性对照组端粒酶相对活性为4.33，试验组 P6代细胞端粒酶相对活性为1.70。因此，本研究的评估结果显示，人脐带间充质干细胞在裸鼠中不致瘤，克隆形成试验结果为阴性，端粒酶活性测定结果正常，具有良好的遗传稳定性。人脐带间充质干细胞在本试验中展现了良好的安全性，具有较好的临床应用价值。
关键词：脐带间充质干细胞；端粒；裸鼠成瘤性；克隆形成试验；安全性
中图分类号：R392.4　　　　　      文献标志码：ADOI：10.3969/j.issn.1007-7146.2022.01.007

Abstract: Stem cell therapy, as a new type of treatment for certain refractory diseases, has important clinical value in the treatment of tissue repair, autoimmune diseases and degenerative diseases. In this study, nude mice were used as animal models to evaluate the safety of human umbilical cord mesenchymal stem cells through experiments such as subcutaneous tumor formation, clone formation and telomerase activity in nude mice, and provide a reference for the safety of stem cells for clinical treatment. The results of the tumorigenicity test in nude mice showed that the number of tumors in the negative control and in the experiment were 0, and the number of tumors in the positive control was 12. The results of the clone formation test showed that the negative control group and the experimental group had no clonal formation, while the positive control group had clone formation. The telomerase activity test results showed that the negative control group had a relative telomerase activity of 0.01, the positive control group had a relative telomerase activity of 4.33, and the relative activity of granzyme for the experimental group which had P6 generation cell was 1.70. Therefore, the evaluation results of this study showed that human umbilical cord mesenchymal stem cells were not tumorigenic in nude mice, and the clone formation test result was negative, the telomerase activity test result was normal and had good genetic stability. Human umbilical cord mesenchymal stem cells showed good safety in this experiment and have good clinical application value.
Key words: umbilical cord mesenchymal stem cells; telomere; tumorigenicity in nude mice; clone formation experiment; safety
（Acta Laser Biology Sinica, 2022, 31(1): 043-049）