Blood Center of Ribeirão Preto - Ribeirão Preto Medical School, University of São Paulo, 2501 Tenente Catão Roxo Avenue, 14051-060, Ribeirão Preto, São Paulo, Brazil.
Blood Center of Ribeirão Preto - Ribeirão Preto Medical School, University of São Paulo, 2501 Tenente Catão Roxo Avenue, 14051-060, Ribeirão Preto, São Paulo, Brazil.
Exp Cell Res. 2021 Feb 1;399(1):112434. doi: 10.1016/j.yexcr.2020.112434. Epub 2020 Dec 16.
It has been suggested that the bone marrow microenvironment harbors two distinct populations of mesenchymal stromal cells (MSC), one with a perivascular location and other present in the endosteum. A better understanding of the biology of these MSC subsets has been pursued in order to refine its clinical application. However, most comparative characterizations of mouse MSC have been performed in normoxia. This can result in misleading interpretations since mouse MSC subsets with low/defective p53 activity are known to be selected during culture in normoxia. Here, we report a comprehensive in vitro characterization of mouse MSC isolated from bone marrow (BM-MSC) and compact bone (CB-MSC) expanded and assayed under hypoxia for their morphology, clonogenic efficiency and differentiation capacity. We found that, under hypoxia, compact bone is richer in absolute numbers of MSC and isolation of MSC from compact bone is associated with a reduced risk of hematopoietic cell carryover. In addition, CB-MSC have higher in vitro osteogenic capacity than BM-MSC, while adipogenic differentiation potential is similar. These findings reinforce the hypothesis of the existence of MSC in bone marrow and compact bone representing functionally distinct cell populations and highlight the compact bone as an efficient source of murine MSC under physiological oxygen concentrations.
有人提出骨髓微环境中存在两种不同的间充质基质细胞（MSC）群体，一种位于血管周围，另一种位于骨内膜。为了完善其临床应用，人们对这些 MSC 亚群的生物学特性进行了深入研究。然而，大多数关于小鼠 MSC 的比较特征都是在常氧条件下进行的。这可能会导致解释上的误导，因为已知在常氧培养条件下，具有低/缺陷 p53 活性的小鼠 MSC 亚群会被选择。在这里，我们报告了一项关于从小鼠骨髓（BM-MSC）和密质骨（CB-MSC）中分离的 MSC 的全面体外特征描述，这些 MSC 在低氧条件下进行扩增和检测，以评估其形态、集落形成效率和分化能力。我们发现，在低氧条件下，密质骨中 MSC 的绝对数量更丰富，且从密质骨中分离 MSC 与减少造血细胞污染的风险相关。此外，CB-MSC 的体外成骨能力高于 BM-MSC，而脂肪生成分化潜力相似。这些发现支持了骨髓和密质骨中存在功能不同的 MSC 群体的假设，并强调了密质骨在生理氧浓度下作为小鼠 MSC 的有效来源。
