Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, The Sahlgrenska Academy, Gothenburg University, Göteborg, Sweden.
Basic Res Cardiol. 2010 Jul;105(4):545-56. doi: 10.1007/s00395-010-0088-1. Epub 2010 Feb 2.
Although numerous reports support the existence of stem cells in the adult heart, few studies have been conducted using human cardiac tissue. Therefore, cells from human cardiac atrial biopsies were analyzed regarding progenitor properties. Expression of stem cell markers was analyzed using fluorescence-activated cell sorting. This identified a small population of C-kit+ cells, which could be further subdivided based on expression of CD45. The C-kit+ CD45+ population was determined to be of mast cell identity, while the C-kit+ CD45- population expressed mRNA of the endothelial lineage. Since the number of cells obtainable from biopsies was limited, a comparison between directly isolated and monolayer and explant cultured cells, respectively, was carried out. While both cultures retained a small population of mast cells, only monolayer culture produced a stable and relatively high percentage of C-kit+ CD45- cells. This population was found to co-express endothelial progenitor cell markers such as CD31, CD34, CXCR4, and FLK-1. The mRNA expression profile was similar to the one from directly isolated cells. When sorted cells were cultured in endothelial differentiation medium, the C-kit+ CD45- population retained its expression of endothelial markers to a large extent, but downregulated progenitor markers, indicating further differentiation into endothelial cells. We have confirmed that the human cardiac atrium contains a small C-kit+ CD45- population expressing markers commonly found on endothelial progenitor cells. The existence of an endothelial progenitor population within the heart might have future implications for developing methods of inducing neovascularization after myocardial infarction.
虽然有大量报告支持成年人心脏中存在干细胞，但使用人类心脏组织进行的研究很少。因此，分析了取自人类心脏心房活检的细胞的祖细胞特性。使用荧光激活细胞分选分析了干细胞标志物的表达。这鉴定了一小部分 C-kit+细胞，这些细胞可以根据 CD45 的表达进一步细分。C-kit+CD45+群体被确定为肥大细胞的身份，而 C-kit+CD45-群体表达内皮谱系的 mRNA。由于从活检中获得的细胞数量有限，因此分别对直接分离和单层及外植体培养的细胞进行了比较。虽然两种培养物都保留了一小部分肥大细胞，但只有单层培养物产生了稳定且相对较高百分比的 C-kit+CD45-细胞。该群体被发现共同表达内皮祖细胞标志物，如 CD31、CD34、CXCR4 和 FLK-1。mRNA 表达谱与直接分离的细胞相似。当分选细胞在内皮细胞分化培养基中培养时，C-kit+CD45-群体在很大程度上保留了其内皮标志物的表达，但下调了祖细胞标志物，表明进一步分化为内皮细胞。我们已经证实，人类心脏心房含有一小部分表达常见于内皮祖细胞的 C-kit+CD45-群体。心脏内存在内皮祖细胞群体可能对开发心肌梗死后诱导新血管生成的方法具有未来意义。
