Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab & Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China.
Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab & Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China; Institute of Functional Nano & Soft Materials (FUNSOM) & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.
Biomaterials. 2015 Jun;53:265-73. doi: 10.1016/j.biomaterials.2015.02.090. Epub 2015 Mar 16.
Mesenchymal stem cells (MSCs) have shown great potential for cutaneous wound regeneration in clinical practice. However, the in vivo homing behavior of intravenously transplanted MSCs to the wounds is still poorly understood. In this work, fluorescence imaging with Ag2S quantum dots (QDs) in the second near-infrared (NIR-II) window was performed to visualize the dynamic homing behavior of transplanted human mesenchymal stem cells (hMSCs) to a cutaneous wound in mice. Benefiting from the desirable spatial and temporal resolution of Ag2S QDs-based NIR-II imaging, for the first time, the migration of hMSCs to the wound was dynamically visualized in vivo. By transplanting a blank collagen scaffold in the wound to help the healing, it was found that hMSCs were slowly recruited at the wound after intravenous injection and were predominantly accumulated around the edge of wound. This resulted in poor healing effects in terms of slow wound closure and thin thickness of the regenerated skin. In contrast, for the wound treated by the collagen scaffold loaded with stromal cell derived factor-1α (SDF-1α), more hMSCs were recruited at the wound within a much shorter time and were homogenously distributed across the whole wound area, which enhances the re-epithelialization, the neovascularization, and accelerates the wound healing.
间充质干细胞 (MSCs) 在临床实践中显示出在皮肤伤口再生方面的巨大潜力。然而，静脉内移植的 MSCs 向伤口的体内归巢行为仍知之甚少。在这项工作中，使用在近红外二区（NIR-II）窗口的 Ag2S 量子点（QDs）进行荧光成像，以可视化移植的人间充质干细胞（hMSCs）向小鼠皮肤伤口的动态归巢行为。受益于基于 Ag2S QDs 的 NIR-II 成像的理想空间和时间分辨率，首次在体内动态可视化 hMSCs 向伤口的迁移。通过在伤口中移植空白胶原支架来帮助愈合，发现静脉注射后 hMSCs 缓慢募集到伤口处，并主要聚集在伤口边缘周围。这导致愈合效果不佳，表现为伤口闭合缓慢且再生皮肤较薄。相比之下，对于用基质细胞衍生因子-1α（SDF-1α）负载的胶原支架处理的伤口，在更短的时间内有更多的 hMSCs 募集到伤口处，并且均匀分布在整个伤口区域，这增强了再上皮化、新生血管形成，并加速了伤口愈合。
