Li Meiying, Xu Jiayi, Mei Xianglin, Chi Guangfan, Li Lisha, Song Yaolin, He Xia, Li Yulin
The Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, Jilin 130021, PR China; Department of Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, PR China.
The Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, Jilin 130021, PR China; Department of Pathology, Central Hospital of Panzhihua, Panzhihua, Sichuan 617067, PR China.
Transpl Immunol. 2019 Feb;52:57-67. doi: 10.1016/j.trim.2018.11.003. Epub 2018 Nov 17.
The M1:M2 macrophage ratio is important for spinal cord injury (SCI) repair. Bone marrow mesenchymal stem cells (BMSCs) can alter macrophage activation, promoting M1 to M2 macrophage conversion and SCI repair; however, clinical BMSC applications have limitations. Previously, we found DPCs to be superior to BMSCs in promoting tissue repair after SCI, which we hypothesized to be mediated by M1 to M2 macrophage conversion. We investigated the regulatory effect of DPCs on M1/M2 macrophage polarization. Dermal papilla cells (DPCs) were isolated from rat vibrissae and characterized. Bone marrow-derived macrophages (BMDMs) were isolated and identified based on specific marker expression, and stimulated to differentiate into M1 macrophages with GM-CSF, IFN-γ, and LPS. These cells were co-cultured with DPCs to evaluate the effect on macrophage differentiation. DPCs expressed dermal papillae-specific markers, including ALP and Sox2, had MSC-expression patterns like those of BMSCs, and were capable of multi-differentiation. BMDMs expressed ANAE and CD68. Three days after induction, differentiated cells exhibited morphology typical of M1-like macrophages and expressed the macrophage marker CD68 and the M1 macrophage markers iNOS, but lacked expression of the M2 macrophage marker CD206. Co-culture with DPCs resulted in a shift to anti-inflammatory M2-like macrophage differentiation, characterized by morphological changes typical of M2 macrophages, downregulation of the characteristic cytokine TNF-α and the proportion of iNOS cells, and upregulation of the characteristic cytokine IL-10 and the cell-surface marker CD206. The number of CD206-expressing M2 macrophages also increased. These findings demonstrate that DPCs reprogram macrophages to an anti-inflammatory M2 phenotype, which could improve adverse inflammatory microenvironments and promote tissue repair. Thus, DPCs may be an interesting alternative cell source and merit further investigation in applications for SCI therapy.
M1与M2巨噬细胞的比例对脊髓损伤（SCI）修复至关重要。骨髓间充质干细胞（BMSC）可改变巨噬细胞的激活状态，促进M1巨噬细胞向M2巨噬细胞转化，进而促进SCI修复；然而，BMSC在临床应用中存在局限性。此前，我们发现牙髓干细胞（DPC）在促进SCI后的组织修复方面优于BMSC，我们推测这是由M1巨噬细胞向M2巨噬细胞转化介导的。我们研究了DPC对M1/M2巨噬细胞极化的调节作用。从大鼠触须中分离并鉴定了真皮乳头细胞（DPC）。基于特定标志物表达分离并鉴定了骨髓来源的巨噬细胞（BMDM），并用粒细胞-巨噬细胞集落刺激因子（GM-CSF）、干扰素-γ（IFN-γ）和脂多糖（LPS）刺激其分化为M1巨噬细胞。将这些细胞与DPC共培养，以评估对巨噬细胞分化的影响。DPC表达真皮乳头特异性标志物，包括碱性磷酸酶（ALP）和性别决定区Y框蛋白2（Sox2），具有与BMSC相似的间充质干细胞表达模式，并且能够多向分化。BMDM表达酸性非特异性酯酶（ANAE）和CD68。诱导三天后，分化细胞呈现出典型的M1样巨噬细胞形态，表达巨噬细胞标志物CD68和M1巨噬细胞标志物诱导型一氧化氮合酶（iNOS），但缺乏M2巨噬细胞标志物CD206的表达。与DPC共培养导致向抗炎性M样巨噬细胞分化转变，其特征为典型的M2巨噬细胞形态变化、特征性细胞因子肿瘤坏死因子-α（TNF-α）和iNOS阳性细胞比例下调，以及特征性细胞因子白细胞介素-10（IL-10）和细胞表面标志物CD206上调。表达CD206的M2巨噬细胞数量也增加。这些发现表明，DPC可将巨噬细胞重编程为抗炎性M2表型，这可以改善不利的炎症微环境并促进组织修复。因此，DPC可能是一种有吸引力的替代细胞来源，值得在SCI治疗应用中进一步研究。
