Center for Translational Oral Research (TOR), Tissue Engineering Group, Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, 5009 Bergen, Norway.
Cells. 2022 Jan 29;11(3):470. doi: 10.3390/cells11030470.
Mesenchymal stromal cells (MSC) loaded on biphasic calcium phosphate biomaterial (MSC + BCP) have been used as an advanced therapy medicinal product to treat complex maxillofacial bone defects in patients. Further, MSC-derived extracellular vesicles (EVs) are established vehicles of paracrine factors, supporting inter-cellular communication between MSC and other interacting cell types, such as monocytes/macrophages. However, the information about the immunomodulatory potential of EVs derived from MSC and biomaterial constructs (MSC + BCP:EV) and inflammatory primed constructs (MSCp + BCP:EV) are scarce. Hence, we isolated and characterized EVs from these different systems, and compared their cytokine contents with plastic-adherent MSC-derived EVs (MSC:EV). When EVs from all three MSC systems were added to the primary blood-derived macrophages in vitro, significantly higher numbers of M0 (naive) macrophages shifted to M2-like (anti-inflammatory) by MSCp + BCP:EV treatment. Further, this treatment led to enhanced switching of M1 polarized macrophages to M2 polarized, and conversely, M2 to M1, as evaluated by determining the M1/M2 ratios after treatment. The enhanced macrophage modulation by MSCp + BCP:EV was attributed to their higher immunomodulatory (TNFα, IL1β, IL5), angiogenic (VEGF), and chemokine-rich (RANTES, MCP1, MIP1β) cytokine cargo. In conclusion, we successfully isolated and characterized EVs from MSC + BCP constructs and demonstrated that, depending upon the tissue microenvironment, these EVs contribute towards modulating the macrophage-mediated inflammation and healing responses. The study offers new insights into the use of biomaterial-induced EVs for MSC secretome delivery, as a step towards future 'cell-free' bone regenerative therapies.
骨髓间充质干细胞（MSC）负载于双相磷酸钙生物材料（MSC+BCP）已被用作治疗患者复杂颌面骨缺损的高级治疗药物。此外，MSC 衍生的细胞外囊泡（EVs）是旁分泌因子的既定载体，支持 MSC 与其他相互作用的细胞类型（如单核细胞/巨噬细胞）之间的细胞间通讯。然而，关于源自 MSC 和生物材料构建体（MSC+BCP:EV）和炎性预刺激构建体（MSCp+BCP:EV）的 EV 的免疫调节潜能的信息却很少。因此，我们从这些不同的系统中分离和表征了 EVs，并将它们的细胞因子含量与塑料贴壁 MSC 衍生的 EVs（MSC:EV）进行了比较。当将来自所有三种 MSC 系统的 EV 添加到体外的原代血源性巨噬细胞中时，MSCp+BCP:EV 处理可使更多的 M0（幼稚）巨噬细胞向 M2 样（抗炎）转变。此外，通过治疗后测定 M1/M2 比值，发现这种治疗方法可促进 M1 极化的巨噬细胞向 M2 极化的转变，反之亦然。MSCp+BCP:EV 对巨噬细胞的增强调节归因于其更高的免疫调节（TNFα、IL1β、IL5）、血管生成（VEGF）和趋化因子丰富（RANTES、MCP1、MIP1β）的细胞因子含量。总之，我们成功地从 MSC+BCP 构建体中分离和表征了 EVs，并表明，根据组织微环境，这些 EV 有助于调节巨噬细胞介导的炎症和愈合反应。该研究为基于生物材料诱导的 EV 用于 MSC 分泌组递呈提供了新的见解，是迈向未来“无细胞”骨再生治疗的一步。
