Centre for Stem Cell Research, Robinson Institute and Department of Medicine, University of Adelaide, South Australia, Australia.
J Cell Physiol. 2010 May;223(2):530-40. doi: 10.1002/jcp.22081.
The cardiovascular therapeutic potential of bone marrow mesenchymal stromal/stem cells (MSC) is largely mediated by paracrine effects. Traditional preparation of MSC has involved plastic adherence-isolation. In contrast, prospective immunoselection aims to improve cell isolation by enriching for mesenchymal precursor cells (MPC) at higher purity. This study compared the biological characteristics and cardiovascular trophic activity of plastic adherence-isolated MSC (PA-MSC) and MPC prepared from the same human donors by immunoselection for stromal precursor antigen-1 (STRO-1). Compared to PA-MSC, STRO-1-MPC displayed greater (1) clonogenicity, (2) proliferative capacity, (3) multilineage differentiation potential, and (4) mRNA expression of mesenchymal stem cell-related transcripts. In vitro assays demonstrated that conditioned medium from STRO-1-MPC had greater paracrine activity than PA-MSC, with respect to cardiac cell proliferation and migration and endothelial cell migration and tube formation. In keeping with this, STRO-1-MPC exhibited higher gene and protein expression of CXCL12 and HGF. Inhibition of these cytokines attenuated endothelial tube formation and cardiac cell proliferation, respectively. Paracrine responses were enhanced by using supernatant from STRO-1(Bright) MPC and diminished with STRO-1(Dim) conditioned medium. Together, these findings indicate that prospective isolation gives rise to mesenchymal progeny that maintain a higher proportion of immature precursor cells compared to traditional plastic adherence-isolation. Enrichment for STRO-1 is also accompanied by increased expression of cardiovascular-relevant cytokines and enhanced trophic activity. Immunoselection thus provides a strategy for improving the cardiovascular reparative potential of mesenchymal cells.
骨髓间充质基质/干细胞（MSC）的心血管治疗潜力在很大程度上是通过旁分泌作用介导的。传统的 MSC 制备涉及塑料贴壁-分离。相比之下，预期免疫选择旨在通过更高纯度富集间充质前体细胞（MPC）来改善细胞分离。本研究比较了通过免疫选择基质前体抗原-1（STRO-1）从同一供体中分离的塑料贴壁分离的 MSC（PA-MSC）和 MPC 的生物学特性和心血管营养活性。与 PA-MSC 相比，STRO-1-MPC 显示出更高的（1）集落形成能力、（2）增殖能力、（3）多能分化潜能和（4）间充质干细胞相关转录物的 mRNA 表达。体外试验表明，STRO-1-MPC 的条件培养基具有比 PA-MSC 更高的旁分泌活性，对心脏细胞增殖和迁移以及内皮细胞迁移和管形成有影响。与此一致，STRO-1-MPC 表现出更高的 CXCL12 和 HGF 基因和蛋白表达。这些细胞因子的抑制分别减弱了内皮管形成和心脏细胞增殖。使用 STRO-1（亮）MPC 的上清液增强了旁分泌反应，而 STRO-1（暗）条件培养基则减弱了反应。总之，这些发现表明，预期分离产生的间充质祖细胞比传统的塑料贴壁分离保留更高比例的不成熟前体细胞。STRO-1 的富集还伴随着心血管相关细胞因子的表达增加和营养活性增强。因此，免疫选择为提高间充质细胞的心血管修复潜力提供了一种策略。
