Myeloid cells, which originate from hematopoietic stem/progenitor cells (HSPCs), play a crucial role in mitigating infections. This study aimed to explore the impact of mesenchymal stem/stromal cells (MSCs) on the differentiation of HSPCs and progenitors through the C-C motif chemokine CCL2/CCR2 signaling pathway. Murine MSCs, identified as PDGFRαSca-1 cells (PαS cells), were found to secrete CCL2, particularly in response to lipopolysaccharide stimulation. MSC-secreted CCL2 promoted the differentiation of granulocyte/macrophage progenitors into the myeloid lineage. MSC-derived CCL2 plays an important role in the early phase of myeloid cell differentiation . Single-cell RNA sequencing analysis confirmed that CCL2-mediated cell fate determination was also observed in human bone marrow cells. These findings provide valuable insights for investigating the effects of MSC transplantation.

中文翻译：

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活化的间充质干细胞/基质细胞通过 CCL2/CCR2 信号传导促进骨髓细胞分化

源自造血干细胞/祖细胞 (HSPC) 的骨髓细胞在减轻感染方面发挥着至关重要的作用。本研究旨在探讨间充质干细胞/基质细胞（MSCs）通过CC基序趋化因子CCL2/CCR2信号通路对HSPCs和祖细胞分化的影响。小鼠 MSC 被鉴定为 PDGFRαSca-1 细胞（PαS 细胞），被发现能够分泌 CCL2，特别是在对脂多糖刺激做出反应时。MSC 分泌的 CCL2 促进粒细胞/巨噬细胞祖细胞分化为骨髓谱系。MSC 衍生的 CCL2 在骨髓细胞分化的早期发挥重要作用。单细胞RNA测序分析证实，在人骨髓细胞中也观察到CCL2介导的细胞命运决定。这些发现为研究间充质干细胞移植的效果提供了宝贵的见解。