Macrophage to myofibroblast transition contributes to subretinal fibrosis secondary to neovascular age-related macular degeneration.
Macrophage to myofibroblast transition contributes to subretinal fibrosis secondary to neovascular age-related macular degeneration.
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DOI：
10.1186/s12974-020-02033-7
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发表时间：
2020-11-25
影响因子：
9.3
通讯作者：
Xu H
中科院分区：
文献类型：
--
作者：
Little K;Llorián-Salvador M;Tang M;Du X;Marry S;Chen M;Xu H
黄斑纤维化导致新生血管性年龄相关性黄斑变性（nAMD）患者无法修复的视力丧失，即使使用抗血管内皮生长因子（VEGF）治疗也是如此。炎症在黄斑纤维化中起重要作用，但其机制尚不清楚。本研究的目的是了解浸润性巨噬细胞和补体蛋白如何导致黄斑纤维化。使用我们小组开发的两阶段激光方案在C57 BL/6 J小鼠中诱导视网膜下纤维化。在第二次激光后10、20、30和40天收集眼睛，并对浸润的巨噬细胞（F4/80和Iba-1）、补体成分（C3 a和C3 aR）和纤维血管病变（胶原蛋白-1，Isolectin B4和α-SMA）进行免疫组织化学处理。患有黄斑纤维化的人视网膜切片也用于该研究。用重组C3 a、C5 a或TGF-β处理来自C57 BL/6 J小鼠的骨髓源性巨噬细胞（BMDM）48和96 h。采用qPCR、Western blot和免疫组织化学方法检测肌成纤维细胞标志物的表达。使用C3 aR拮抗剂（C3 aRA）和C3 a阻断抗体在体外和体内进一步研究了C3 a-C3 aR通路在巨噬细胞向肌成纤维细胞转化（MMT）和视网膜下纤维化中的参与。在nAMD和小鼠模型中，约20~30%的F4/80+（或Iba-1+）浸润巨噬细胞共表达α-SMA。TGF-β和C3 a（但不是C5 a处理）显着上调BMDM中α-SMA、纤连蛋白和胶原蛋白-1的表达。C3 aRA治疗阻止了C3 a诱导的BMDM中α-SMA、纤连蛋白和胶原-1的上调。在诱导视网膜下纤维化的两阶段激光模型中，用C3 a阻断抗体而不是C3 aRA治疗显著减少了血管渗漏和Isolectin B4+病变。治疗未显著改变胶原-1+纤维化病变。MMT在继发于nAMD的黄斑纤维化中起作用。TGF-β和C3 a可诱导MMT的产生，而C5 a则不能诱导MMT的产生。需要进一步的研究来充分了解MMT在黄斑纤维化中的作用。巨噬细胞向肌成纤维细胞转化（MMT）有助于视网膜下纤维化。视网膜下纤维化病变含有各种细胞类型，包括巨噬细胞和肌成纤维细胞，并且是纤维血管性的。肌成纤维细胞是驱动致病性纤维化的关键细胞，并且它们通过产生过量的细胞外基质蛋白来这样做。我们已经发现浸润的巨噬细胞可以转分化成肌成纤维细胞，这是黄斑纤维化中称为巨噬细胞向肌成纤维细胞转化（MMT）的现象。除TGF-β1外，在CNV中补体激活期间产生的C3 a也可诱导MMT，从而导致黄斑纤维化。RPE =视网膜色素上皮。BM =布鲁赫膜。MMT =巨噬细胞向肌成纤维细胞转化。TGFB =转化生长因子β。α-SMA = α平滑肌肌动蛋白。C3 a =补体C3 a。
Macular fibrosis causes irreparable vision loss in neovascular age-related macular degeneration (nAMD) even with anti-vascular endothelial growth factor (VEGF) therapy. Inflammation is known to play an important role in macular fibrosis although the underlying mechanism remains poorly defined. The aim of this study was to understand how infiltrating macrophages and complement proteins may contribute to macular fibrosis. Subretinal fibrosis was induced in C57BL/6J mice using the two-stage laser protocol developed by our group. The eyes were collected at 10, 20, 30 and 40 days after the second laser and processed for immunohistochemistry for infiltrating macrophages (F4/80 and Iba-1), complement components (C3a and C3aR) and fibrovascular lesions (collagen-1, Isolectin B4 and α-SMA). Human retinal sections with macular fibrosis were also used in the study. Bone marrow-derived macrophages (BMDMs) from C57BL/6J mice were treated with recombinant C3a, C5a or TGF-β for 48 and 96 h. qPCR, Western blot and immunohistochemistry were used to examine the expression of myofibroblast markers. The involvement of C3a-C3aR pathway in macrophage to myofibroblast transition (MMT) and subretinal fibrosis was further investigated using a C3aR antagonist (C3aRA) and a C3a blocking antibody in vitro and in vivo. Approximately 20~30% of F4/80+ (or Iba-1+) infiltrating macrophages co-expressed α-SMA in subretinal fibrotic lesions both in human nAMD eyes and in the mouse model. TGF-β and C3a, but not C5a treatment, significantly upregulated expression of α-SMA, fibronectin and collagen-1 in BMDMs. C3a-induced upregulation of α-SMA, fibronectin and collagen-1 in BMDMs was prevented by C3aRA treatment. In the two-stage laser model of induced subretinal fibrosis, treatment with C3a blocking antibody but not C3aRA significantly reduced vascular leakage and Isolectin B4+ lesions. The treatment did not significantly alter collagen-1+ fibrotic lesions. MMT plays a role in macular fibrosis secondary to nAMD. MMT can be induced by TGF-β and C3a but not C5a. Further research is required to fully understand the role of MMT in macular fibrosis. Macrophage to myofibroblast transition (MMT) contributes to subretinal fibrosis. Subretinal fibrosis lesions contain various cell types, including macrophages and myofibroblasts, and are fibrovascular. Myofibroblasts are key cells driving pathogenic fibrosis, and they do so by producing excessive amount of extracellular matrix proteins. We have found that infiltrating macrophages can transdifferentiate into myofibroblasts, a phenomenon termed macrophage to myofibroblast transition (MMT) in macular fibrosis. In addition to TGF-β1, C3a generated during complement activation in CNV can also induce MMT contributing to macular fibrosis. RPE = retinal pigment epithelium. BM = Bruch’s membrane. MMT = macrophage to myofibroblast transition. TGFB = transforming growth factor β. a-SMA = alpha smooth muscle actin. C3a = complement C3a.
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影响因子：
4.4
作者：
Chen, Mei;Luo, Chang;Xu, Heping
通讯作者：
Xu, Heping
影响因子：
--
作者：
Stevens, TS;Bressler, NM;Schachat, AP
通讯作者：
Schachat, AP
影响因子：
3.4
作者：
Luo, Chang;Zhao, Jiawu;Xu, Heping
通讯作者：
Xu, Heping
DOI：
10.1186/s12979-016-0060-5
发表时间：
2016
期刊：
Immunity & ageing : I & A
影响因子：
--
作者：
Lechner J;Chen M;Hogg RE;Toth L;Silvestri G;Chakravarthy U;Xu H
通讯作者：
Xu H
影响因子：
3
作者：
Little, Karis;Llorian-Salvador, Maria;Xu, Heping
通讯作者：
Xu, Heping