两个部位脂肪来源干细胞的心肌细胞分化潜能比较

Comparison of cardiomyogenic potentials of adipose-derived stromal stem cells from the pericardial and the groin fat tissues

目的比较心包部位和腹股沟部位脂肪组织来源干细胞(ADSC)的免疫表型和分化潜能。方法取Wistar大鼠心包组织和腹股沟脂肪,消化分离原代ADSC,分别用流式细胞技术和免疫组织化学法检测两个部位ADSC的免疫表型和心肌源性转录因子的表达,并进一步用5-氮杂胞苷分别诱导两个部位的ADSC向心肌细胞分化,分析诱导后心脏肌钙蛋白T(cTnT)的表达。结果两个部位的ADSC具有相同的免疫表型:均为CD29、CD44、CD90阳性和CD34、CD45阴性细胞。原代心包部位的ADSC可以检测到少量cTnT阳性细胞,并有不同程度的GATA-4、Isl-1、Nkx-2.5和MEF-2c表达;而原代腹股沟部位的ADSC除了Isl-1呈弱阳性表达外,其他因子均为阴性表达。两个部位的ADSC经诱导均定向分化成心肌细胞,但心包部位的ADSC的心肌分化能力大于腹股沟部位的ADSC(53%与32%,P<0.01)。结论不同部位的ADSC有共同的形态和免疫表型。心包部位的ADSC在转录因子和cTnT表达方面体现出较强的心肌分化潜能。

Objective To compare the immune phenotype and the myogenic potential of 2 adipose tissuederived stem cell （ADSC） populations from the pericardial tissue and the groin in rats. Methods The 2 ADSC populations were cultured from the pericardia1 tissue and the groin tissue in Wistar rats. The immune phenotypes of the 2 ADSC populations were evaluated by flow cytometry and the expression of myocardium derived transcription factors was assessed by immunohistochemistry. After ADSC being induced to cardiomyocytes, the expression of cardiac troponin T （cTnT） was detected in 2 ADSC groups. Results Flow cytometry analysis showed that the 2 ADSC populations shared identical immune phenotypes, i.e. positive for CD29, CD44 and CD90, but negative for CD34 and CD45. However, the pericardial ADSC showed a various extent expression of GATA4 （62% ＋ 19% ）, lsl1 （41% ＋ 13%）, Nkx2.5 （4.3% ＋2%）, and MEF2c （32% ＋ 11%）. Most interestingly, the pericardial ADSC exhibited greater potential of myogenic differentiation, marked by the expression of cTnT, than the groin derived ADSC （53% vs 32%, P 〈 0.01 ）. Conclusion Pericardial ADSC shared biologically comparable properties to cardiac stem cells and represented an attracting cell source for cardiac cellular therapy.