脐带间充质干细胞体外传代培养后细胞核型稳定性

A Research on Karyotype Stability of Human Umbilical Cord Mesenchymal Stem Cells during Culture in vitro

目的：研究脐带间充质干细胞（uc-MSCs）在经过培养和传代后是否会出现染色体异常改变。方法：收集剖宫产足月胎儿脐带，采用胶原酶加胰酶消化法和机械法分离出UC-MSCs间充质干细胞贴壁培养传代，观察细胞形态、免疫表型及细胞增殖实验等生物学特性，利用G显带分析原代（Po）和第3～6代（P3～P6）细胞的染色体核型。结果：染色体核型分析显示,P0和P3～P6UC-MSCs均为正常二倍体核型，G显带未见染色体结构异常；UC-MSCs呈成纤维样形态生长，P3～P6代高表达CD73、CD90、CD44，并且UC-MSCs在培养2～3d时达到对数增长期。结论：UC-MSCs在体外连续传代培养6代以内染色体结构稳定，未出现染色体异常改变。

Objective： To investigate whether the chromosomes of human umbilical cord mesenchymal stem cells （UC-MSCs） will change after being cultured in vitro for generations. Methods： Umbilical cords of cesarean delivery were collected aseptically. UC-MSCs were isolated by digestion with collagenase and trypsin or mechanical methods, and were cultured in vitro. The cells were characterized by morphology,immunophenotype and cell proliferation test, and karyotypes of generations of P0, P3, P4, PS, and P6 were analyzed with G-banding technique. Results： The karyotype analysis showed a normal diploid karyotype with 46 chromosomes and no abnormal change was found in chromosome structure. UC-MSCs exhibited fibroblastic morphology and CD73, CD90, and CD44 highly expressed in generations P3 - P6. Cells reached logarithmic growth phase in 2 ~ 3 days of culture. Conclusion： When cultured for 6 passages in vitro, UC-MSCs can maintain stable chromosome structure,which provides an experimental basis for the safety of UC-MSCs cytotherapy.