Department of Clinical Laboratory, The Affiliated Changzhou Second People's Hospital of Nanjing Medical University, Changzhou, 213000, Jiangsu, China.
Department of Pediatrics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
Inflammation. 2023 Dec;46(6):2241-2253. doi: 10.1007/s10753-023-01874-7. Epub 2023 Aug 2.
Our previous study had demonstrated that Runx1 promoted LPS-induced macrophage inflammatory response, however, the role of Runx1 in M2 macrophage polarization still remains largely unknown. This study was conducted to investigate the role of Runx1 in IL-4/IL-13-induced M2 macrophage polarization and its potential regulatory mechanism. We found that exposure of macrophages to IL-4/IL-13 induced a remarkable increasement in Runx1 expression level. Specifically, we established genetically modified mice lacking Runx1 in myeloid cells, including macrophages. RNA-Seq was performed to identify differentially expressed genes (DEGs) between Runx1 knockout and WT control bone marrow-derived macrophages (BMDMs). We identified 686 DEGs, including many genes which were highly expressed in M2 macrophage. In addition, bioinformatics analysis indicated that these DEGs were significantly enriched in extracellular matrix-related processes. Moreover, RT-qPCR analysis showed that there was an obvious upregulation in the relative expression levels of M2 marker genes, including Arg1, Ym1, Fizz1, CD71, Mmp9, and Tgm2, in Runx1 knockout macrophages, as compared to WT controls. Consistently, similar results were obtained in the protein and enzymatic activity levels of Arg1. Finally, we found that the STAT6 phosphorylation level was significantly enhanced in Runx1 knockout macrophages, and the STAT6 inhibitor AS1517499 partly reduced the upregulated effect of Runx1 deficiency on the M2 macrophage polarization. Taken together, Runx1 deficiency facilitates IL-4/IL-13-induced M2 macrophage polarization through enhancing STAT6 phosphorylation.
我们之前的研究表明 Runx1 促进 LPS 诱导的巨噬细胞炎症反应，然而，Runx1 在 M2 巨噬细胞极化中的作用在很大程度上仍然未知。本研究旨在探讨 Runx1 在 IL-4/IL-13 诱导的 M2 巨噬细胞极化中的作用及其潜在的调节机制。我们发现，巨噬细胞暴露于 IL-4/IL-13 会显著增加 Runx1 的表达水平。具体来说，我们构建了骨髓来源的巨噬细胞（BMDMs）中缺失 Runx1 的基因敲除小鼠。进行 RNA-Seq 以鉴定 Runx1 敲除和 WT 对照 BMDMs 之间差异表达的基因（DEGs）。我们鉴定了 686 个 DEGs，其中包括许多在 M2 巨噬细胞中高度表达的基因。此外，生物信息学分析表明，这些 DEGs 显著富集于细胞外基质相关过程。此外，RT-qPCR 分析显示，与 WT 对照组相比，Runx1 敲除巨噬细胞中 M2 标志物基因（包括 Arg1、Ym1、Fizz1、CD71、Mmp9 和 Tgm2）的相对表达水平明显上调。同样，Arg1 的蛋白和酶活性水平也得到了类似的结果。最后，我们发现 Runx1 敲除巨噬细胞中 STAT6 磷酸化水平显著增强，而 STAT6 抑制剂 AS1517499 部分减弱了 Runx1 缺失对 M2 巨噬细胞极化的上调作用。总之，Runx1 缺失通过增强 STAT6 磷酸化促进 IL-4/IL-13 诱导的 M2 巨噬细胞极化。
