体外连续传代培养脐带间充质干细胞染色体核型的稳定性

目的分析不同代次人脐带间充质干细胞（umbilical cord mesenchymal stern cells，UC—MSCs）的染色体核型，初步评价UC—MSCs在体外连续传代培养过程中染色体结构的稳定性。方法采用胶原酶消化法分离UC—MSCs，贴壁培养传代，通过细胞形态、免疫表型及多向分化潜能等生物学特性进行鉴定，利用G显带分析第3、5、7代细胞的染色体核型。结果染色体核型分析显示，第3、5、7代UC-MSCs为正常二倍体核型，G显带未见染色体结构异常。，UC—MSCs呈成纤维样形态生长，高表达CD73、CD90、CDl05，不表达CD34、CIM5、CD40、CD80、CD86、CDl54、HLA—DR；在特定的体外诱导条件下可以向骨、脂肪、软骨分化。结论UC-MSCs在体外连续传代培养7代以内染色体结构稳定，为临床应用UC—MSCs的安全性提供了遗传学方面的实验依据。

Karyotype stability of human umbilical cord mesenchymal stem cells during culture in vitro

Objective To analyze the karyotype of human umbilical cord mesenchymal stem cells （UC-MSCs） and to evaluate the stability of chromosome structure of UC-MSCs during continuous passaging in vitro. Methods The UC-MSCs were isolated by digestion with collagenase and subcuhured in vitro. They were characterized by morphology, immunophe- notype and multi-directional differentiation potential. Furthermore, the karyotype of passage 3 （ P3 ）, P5 and P7 UC-MSCs was analyzed by G-banding technique. Results The karyotype analysis of P3, P5 and P7 UC-MSCs showed a normal dip- loid karyotype with 46 chromosomes and there were no abnormal changes in chromosome structure. UC-MSCs exhibited fibroblastic morphology and were CD73, CD90, and CD105 positive and CD34, CD45, CD40, CDS0, CD86, CD154, and HLA-DR negative. Under special induction conditions, UC-MSCs could differentiate into osteocytes, adipocytes and chondro- cytes, Conclusion When cultured for 7 passages in vitro, UC-MSCs can maintain stable chromosome structure, which pro- vides an experimental basis for the safety of UC-MSCs eytotherapy.