Impaired Autophagic Degradation of Transforming Growth Factor-β-Induced Protein by Macrophages in Lattice Corneal Dystrophy
Impaired Autophagic Degradation of Transforming Growth Factor-β-Induced Protein by Macrophages in Lattice Corneal Dystrophy
复制标题
格子角膜营养不良中巨噬细胞对转化生长因子-β诱导蛋白的自噬降解受损
DOI：
10.1167/iovs.18-25838
复制
发表时间：
2019-03-01
影响因子：
4.4
通讯作者：
Zheng, Zhen-You
中科院分区：
文献类型：
--
作者：
Han, Ji;Zhang, Ming;Zheng, Zhen-You
目的.格子状角膜营养不良（LCD）与转化生长因子β诱导蛋白（TGF β 1 β）的变性有关。巨噬细胞对变性蛋白的自噬降解是其清除变性蛋白的途径之一。因此，我们研究了自噬在巨噬细胞中降解突变型（MU）TGF β 1 β中的作用。通过裂隙灯摄影观察参与者的角膜，并进行组织病理学和遗传学分析。重组并表达野生型（WT）和MU TGF β 1 β。分离来自MU参与者的巨噬细胞并与重组TGF β 1 β共培养。通过免疫荧光显微镜观察到两种分子的共定位。酶联免疫吸附试验，蛋白质印迹和流式细胞术被用来检测分子表达的变化与表型和自噬过程。一个25人的家庭中有14名成员被确定为LCD患者。仅在LCD患者的角膜中发现显著的TGF β 1 β聚集体和巨噬细胞浸润。在暴露于MU TGF β 1 β的巨噬细胞中发现TGF β 1 β的标记物积累，甚至在MU TGF β 1 β被撤回后5小时。在暴露于WT TGF β 1 β的巨噬细胞中发现了高表达的⑶ 68和⑶ 36，但在暴露于MU TGF β 1 β的巨噬细胞中没有发现。在暴露于MU TGF β 1 β的巨噬细胞中发现由于自噬体与溶酶体融合缺陷导致的自噬通量受损。自噬过程的阻断抑制了暴露于WT TGF β 1 β的巨噬细胞中CD68和CD36的表达，其水平与暴露于MU TGF β 1 β的巨噬细胞中发现的水平相似。我们的研究结果表明，逆转巨噬细胞中有缺陷的自噬过程可能是LCD患者的治疗策略。
PURPOSE. Lattice corneal dystrophy (LCD) is related to the denaturation of transforming growth factor-beta-induced protein (TGFBIp). Autophagic degradation of the denatured proteins by macrophages is one pathway to remove the denatured proteins. Thus, we investigated the role of autophagy in the degradation of mutant (MU) TGFBIp in macrophages.METHODS. Corneas from participants were observed by slit-lamp photography and subjected to histopathologic and genetic analysis. Wild-type (WT) and MU TGFBIp were recombined and expressed. Macrophages from MU participants were isolated and cocultured with the recombinant TGFBIp. Colocalization of the two molecules was observed by immunofluorescent microscopy. Enzyme-linked immunosorbent assay, Western blotting, and flow cytometry were used to detect changes in molecule expression related to the phenotype and autophagy process.RESULTS. Fourteen members from a family of 25 were identified as LCD sufferers. Significant TGFBIp aggregates and macrophage infiltration were found only in the corneas of LCD sufferers. Marker accumulation of TGFBIp was found in macrophages exposed to MU TGFBIp even at 5 hours after MU TGFBIp was withdrawn. High expressions of CD68 and CD36 were found in macrophages exposed to WT TGFBIp, but not to MU TGFBIp. Impaired autophagic flux due to defective autophagosome fusion to lysosomes was found in macrophages exposed to MU TGFBIp. Blockage of the autophagic process suppressed the expression of CD68 and CD36 in macrophages exposed to WT TGFBIp to levels similar to those found in macrophages exposed to MU TGFBIp.CONCLUSIONS. Our results suggested that reversion of the defective autophagic process in macrophages may be a therapeutic strategy for patients with LCD.