Medical School of Chinese People's Liberation Army, Beijing, China.
Department of Dermatology, the Seventh Medical Center of Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.
Front Immunol. 2023 Mar 6;14:1142088. doi: 10.3389/fimmu.2023.1142088. eCollection 2023.
Full-thickness skin wound healing remains a serious undertaking for patients. While stem cell-derived exosomes have been proposed as a potential therapeutic approach, the underlying mechanism of action has yet to be fully elucidated. The current study aimed to investigate the impact of exosomes derived from human umbilical cord mesenchymal stem cells (hucMSC-Exosomes) on the single-cell transcriptome of neutrophils and macrophages in the context of wound healing.
Utilizing single-cell RNA sequencing, the transcriptomic diversity of neutrophils and macrophages was analyzed in order to predict the cellular fate of these immune cells under the influence of hucMSC-Exosomes and to identify alterations of ligand-receptor interactions that may influence the wound microenvironment. The validity of the findings obtained from this analysis was subsequently corroborated by immunofluorescence, ELISA, and qRT-PCR. Neutrophil origins were characterized based on RNA velocity profiles.
The expression of and was associated with migrating neutrophils, while was linked to proliferating neutrophils. The hucMSC-Exosomes group exhibited significantly higher levels of M1 macrophages (215 vs 76, p < 0.00001), M2 macrophages (1231 vs 670, p < 0.00001), and neutrophils (930 vs 157, p < 0.00001) when compared to control group. Additionally, it was observed that hucMSC-Exosomes elicit alterations in the differentiation trajectories of macrophages towards more anti-inflammatory phenotypes, concomitant with changes in ligand-receptor interactions, thereby facilitating healing.
This study has revealed the transcriptomic heterogeneity of neutrophils and macrophages in the context of skin wound repair following hucMSC-Exosomes interventions, providing a deeper understanding of cellular responses to hucMSC-Exosomes, a rising target of wound healing intervention.
全层皮肤伤口愈合仍然是患者面临的一项严峻挑战。虽然干细胞衍生的外泌体已被提出作为一种潜在的治疗方法，但作用机制尚未完全阐明。本研究旨在探讨人脐带间充质干细胞（hucMSC-Exosomes）衍生的外泌体对伤口愈合过程中中性粒细胞和巨噬细胞单细胞转录组的影响。
利用单细胞 RNA 测序，分析中性粒细胞和巨噬细胞的转录组多样性，以预测这些免疫细胞在 hucMSC-Exosomes 影响下的细胞命运，并确定可能影响伤口微环境的配体-受体相互作用的变化。通过免疫荧光、ELISA 和 qRT-PCR 对分析结果进行验证。根据 RNA 速度图谱对中性粒细胞的起源进行了特征描述。
和 的表达与迁移的中性粒细胞有关，而 与增殖的中性粒细胞有关。与对照组相比，hucMSC-Exosomes 组的 M1 巨噬细胞（215 对 76，p < 0.00001）、M2 巨噬细胞（1231 对 670，p < 0.00001）和中性粒细胞（930 对 157，p < 0.00001）的水平显著升高。此外，还观察到 hucMSC-Exosomes 引起巨噬细胞向更抗炎表型的分化轨迹发生改变，同时配体-受体相互作用发生变化，从而促进愈合。
本研究揭示了 hucMSC-Exosomes 干预皮肤伤口修复过程中中性粒细胞和巨噬细胞的转录组异质性，深入了解细胞对 hucMSC-Exosomes 的反应，这是伤口愈合干预的一个新兴靶点。
