Department of Orthopaedics, UHealth Sports Medicine Institute, University of Miami, Miller School of Medicine, Miami, Florida, USA.
Diabetes Research Institute & Cell Transplantation Center, University of Miami, Miller School of Medicine, Miami, Florida, USA.
Stem Cells. 2020 Aug;38(8):1034-1049. doi: 10.1002/stem.3196. Epub 2020 May 16.
CD146 bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) play key roles in the perivascular niche, skeletogenesis, and hematopoietic support; however, comprehensive evaluation of therapeutic potency has yet to be determined. In this study, in vitro inflammatory priming to crude human BM-MSCs (n = 8) captured a baseline of signature responses, including enriched CD146 with coexpression of CD107a , CXCR4 , and LepR , transcriptional profile, enhanced secretory capacity, and robust immunomodulatory secretome and function, including immunopotency assays (IPAs) with stimulated immune cells. These signatures were significantly more pronounced in CD146 (POS)-sorted subpopulation than in the CD146 (NEG). Mechanistically, POS BM-MSCs showed a markedly higher secretory capacity with significantly greater immunomodulatory and anti-inflammatory protein production upon inflammatory priming compared with the NEG BM-MSCs. Moreover, IPAs with stimulated peripheral blood mononuclear cells and T lymphocytes demonstrated robust immunosuppression mediated by POS BM-MSC while inducing significant frequencies of regulatory T cells. in vivo evidence showed that POS BM-MSC treatment promoted pronounced M1-to-M2 macrophage polarization, ameliorating inflammation/fibrosis of knee synovium and fat pad, unlike treatment with NEG BM-MSCs. These data correlate the expression of CD146 with innately higher immunomodulatory and secretory capacity, and thus therapeutic potency. This high-content, reproducible evidence suggests that the CD146 (POS) MSC subpopulation are the mediators of the beneficial effects achieved using crude BM-MSCs, leading to translational implications for improving cell therapy and manufacturing.
CD146 骨髓源性间充质干细胞（BM-MSCs）在血管周龛、骨生成和造血支持中发挥关键作用；然而，其治疗效力的综合评估尚未确定。在这项研究中，对粗制人 BM-MSCs（n = 8）进行体外炎症预刺激，捕捉到特征性反应的基线，包括富含 CD146，同时表达 CD107a、CXCR4 和 LepR，转录谱、增强的分泌能力，以及强大的免疫调节分泌组和功能，包括用刺激免疫细胞进行免疫潜力测定（IPA）。这些特征在 CD146（POS）分选亚群中比在 CD146（NEG）中更为显著。从机制上讲，与 NEG BM-MSCs 相比，POS BM-MSCs 在炎症预刺激时表现出明显更高的分泌能力，具有显著更高的免疫调节和抗炎蛋白产生。此外，用刺激的外周血单核细胞和 T 淋巴细胞进行 IPA 显示，POS BM-MSC 介导的强大免疫抑制作用同时诱导了调节性 T 细胞的显著频率。体内证据表明，POS BM-MSC 治疗可促进明显的 M1 向 M2 巨噬细胞极化，改善膝关节滑膜和脂肪垫的炎症/纤维化，与 NEG BM-MSC 治疗不同。这些数据将 CD146 的表达与先天更高的免疫调节和分泌能力相关联，从而与治疗效力相关联。这种高内涵、可重复的证据表明，CD146（POS）MSC 亚群是使用粗制 BM-MSC 实现有益效果的介导物，为改善细胞治疗和制造带来转化意义。
