Children's Hospital Boston, Harvard Medical School, Boston, MA, USA.
Biol Cell. 2011 Sep;103(9):435-47. doi: 10.1042/BC20110033.
Recent research has shown that adipose tissues contain abundant MSCs (mesenchymal stem cells). The origin and location of the adipose stem cells, however, remain unknown, presenting an obstacle to the further purification and study of these cells. In the present study, we aimed at investigating the origins of adipose stem cells. α-SMA (α-smooth muscle actin) is one of the markers of pericytes. We harvested ASCs (adipose stromal cells) from α-SMA-GFP (green fluorescent protein) transgenic mice and sorted them into GFP-positive and GFP-negative cells by FACS. Multilineage differentiation tests were applied to examine the pluripotent ability of the α-SMA-GFP-positive and -negative cells. Immunofluorescent staining for α-SMA and PDGF-Rβ (platelet-derived growth factor receptor β) were applied to identify the α-SMA-GFP-positive cells. Then α-SMA-GFP-positive cells were loaded on a collagen-fibronectin gel with endothelial cells to test their vascularization ability both in vitro and in vivo. Results show that, in adipose tissue, all of the α-SMA-GFP-positive cells congregate around the blood vessels. Only the α-SMA-GFP-positive cells have multilineage differentiation ability, while the α-SMA-GFP-negative cells can only differentiate in an adipogenic direction. The α-SMA-GFP-positive cells maintained expression of α-SMA during multilineage differentiation. The α-SMA-GFP-positive cells can promote the vascularization of endothelial cells in three-dimensional culture both in vitro and in vivo. We conclude that the adipose stem cells originate from perivascular cells and congregate around blood vessels.
最近的研究表明，脂肪组织中含有丰富的间充质干细胞（MSC）。然而，脂肪干细胞的起源和位置尚不清楚，这给这些细胞的进一步纯化和研究带来了障碍。在本研究中，我们旨在研究脂肪干细胞的起源。α-SMA（α-平滑肌肌动蛋白）是周细胞的标志物之一。我们从α-SMA-GFP（绿色荧光蛋白）转基因小鼠中提取 ASCs（脂肪基质细胞），并通过 FACS 将其分选成 GFP 阳性和 GFP 阴性细胞。多能性分化试验用于检测α-SMA-GFP 阳性和阴性细胞的多能性。应用免疫荧光染色检测α-SMA 和 PDGF-Rβ（血小板衍生生长因子受体β）以鉴定α-SMA-GFP 阳性细胞。然后将α-SMA-GFP 阳性细胞加载到含有内皮细胞的胶原蛋白-纤维连接蛋白凝胶上，以测试其体外和体内的血管生成能力。结果表明，在脂肪组织中，所有的α-SMA-GFP 阳性细胞都聚集在血管周围。只有α-SMA-GFP 阳性细胞具有多能性分化能力，而α-SMA-GFP 阴性细胞只能向脂肪方向分化。α-SMA-GFP 阳性细胞在多能性分化过程中保持α-SMA 的表达。α-SMA-GFP 阳性细胞可促进三维培养中外源内皮细胞的血管生成。我们得出结论，脂肪干细胞来源于血管周围细胞，并聚集在血管周围。
