Mesenchymal stem cells (MSCs) are the likely precursors of multiple lines of mesenchymal cells. The existence of bona fide MSCs with self-renewal capacity and differentiation potential into all mesenchymal lineages, however, has been unclear because of the lack of MSC-specific marker(s) that are not expressed by the terminally differentiated progeny. Meflin, a glycosylphosphatidylinositol-anchored protein, is an MSC marker candidate that is specifically expressed in rare stromal cells in all tissues. Our previous report showed that Meflin expression becomes down-regulated in bone marrow-derived MSCs cultured on plastic, making it difficult to examine the self-renewal and differentiation of Meflin-positive cells at the single-cell level. Here, we traced the lineage of Meflin-positive cells in postnatal and adult mice, showing that those cells differentiated into white and brown adipocytes, osteocytes, chondrocytes and skeletal myocytes. Interestingly, cells derived from Meflin-positive cells formed clusters of differentiated cells, implying the in situ proliferation of Meflin-positive cells or their lineage-committed progenitors. These results, taken together with previous findings that Meflin expression in cultured MSCs was lost upon their multilineage differentiation, suggest that Meflin is a useful potential marker to localize MSCs and/or their immature progenitors in multiple tissues.

中文翻译：

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Meflin 定义了具有多向分化能力的间充质干细胞和/或其早期祖细胞

间充质干细胞 (MSC) 可能是多系间充质细胞的前体。善意的存在然而，具有自我更新能力和分化成所有间充质谱系的潜能的 MSC 一直不清楚，因为缺乏不由终末分化后代表达的 MSC 特异性标记。Meflin 是一种糖基磷脂酰肌醇锚定蛋白，是一种 MSC 标记候选物，在所有组织中的稀有基质细胞中均特异性表达。我们之前的报告表明，在塑料上培养的骨髓来源的 MSC 中，Meflin 的表达下调，因此很难在单细胞水平上检查 Meflin 阳性细胞的自我更新和分化。在这里，我们追踪了出生后和成年小鼠中 Meflin 阳性细胞的谱系，表明这些细胞分化为白色和棕色脂肪细胞、骨细胞、软骨细胞和骨骼肌细胞。有趣的是，源自 Meflin 阳性细胞的细胞形成分化细胞簇，这意味着 Meflin 阳性细胞或其谱系定向祖细胞的原位增殖。这些结果与之前的发现相结合，即培养的 MSC 中的 Meflin 表达在其多向分化时丢失，表明 Meflin 是一种有用的潜在标志物，可用于在多个组织中定位 MSC 和/或其未成熟祖细胞。