Neural stem cells transplanted to the subretinal space of rd1 mice delay retinal degeneration by suppressing microglia activation
Neural stem cells transplanted to the subretinal space of rd1 mice delay retinal degeneration by suppressing microglia activation
复制标题
移植到 rd1 小鼠视网膜下腔的神经干细胞通过抑制小胶质细胞激活来延缓视网膜变性
DOI：
10.1016/j.jcyt.2016.03.001
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发表时间：
2016-06-01
期刊：
影响因子：
4.5
通讯作者：
Yin, Zheng Qin
中科院分区：
文献类型：
--
作者：
Li, Zhengya;Zeng, Yuxiao;Yin, Zheng Qin
背景目标。视网膜变性（RD）是一种以不可逆的光感受器丧失为特征的遗传性眼病。通常，常驻小胶质细胞的激活是继发于疾病的。基于干细胞的治疗最近在治疗RD方面取得了快速进展。虽然已经证明干细胞治疗的作用可能包括免疫调节，但具体机制尚未阐明。方法.采用免疫细胞化学、末端脱氧核苷酸转移酶缺口末端标记法（TUNEL）和Western blot分析rd 1小鼠视网膜小胶质细胞活化和感光细胞凋亡。将GFP-C17.2神经干细胞（NSCs）植入视网膜下腔，观察其免疫调节和神经保护作用。将GFP-C17.2与BV 2细胞共培养，观察GFP-C17.2对BV 2细胞增殖、凋亡及炎性因子分泌的影响。采用真实的时间定量聚合酶链反应（RT-qPCR）和酶联免疫吸附试验（ELISA）检测NSCs和小胶质细胞分泌因子的基因和蛋白水平。结果TUNEL阳性细胞主要分布于P8 d的rd 1小鼠的内核层（INL），P10 d出现在外核层（ONL），P14 d达到高峰。同时，小胶质细胞迁移到ONL并达到最大水平，伴随着Fractalkine及其独特受体CX 3CR 1蛋白水平的变化。将P7 d的NSCs移植到rd 1小鼠视网膜下腔后，可抑制小胶质细胞的活化，延缓ONL的变性。此外，在体外共培养的神经干细胞抑制小胶质细胞的活化。在此共培养体系中，NSCs中的金属蛋白酶组织抑制因子（TIMP 1）的基因和蛋白水平升高，而BV 2小胶质细胞中的基质金属蛋白酶（MMP 9）的基因和蛋白水平明显受到抑制。结论.移植于视网膜的神经干细胞对小胶质细胞具有免疫调节作用，从而延缓了光感受器的退化。
Background aims. Retinal degeneration (RD) is an inherited eye disease characterized by irreversible photoreceptor loss. Conventionally, the activation of the resident microglia is secondary to the disease. Stem cell based therapy has recently made rapid progress in treating RD. Although it has been demonstrated that the effect of stem cell therapy may include immunomodulation, the specific mechanisms have not been clarified. Methods. Immunocytochemistry, terminal deoxynucleotidyl transferase UTP nick end labelling (TUNEL) assay and Western blot were used to analyze the microglia activation and photoreceptor apoptosis in the retina of rd1 mice. GFP-C17.2 neural stem cells (NSCs) were transplanted into the subretinal space to study the immunomodulatory and neuroprotective effects. The transwell co-culture of BV2 cells with GFP-C17.2 was performed to study the proliferation, apoptosis and secretion levels of inflammatory factors. Real time-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) were performed to explore the gene and protein level of factors secreted by NSCs and microglia. Results. TUNEL-positive cells were primarily distributed in the inner nuclear, layer (INL) of rd1 mice on P8d, appeared in the outer nuclear layer (ONL) on P10d and peaked on P14d. Meanwhile, microglia migrated to the ONL and reached the maximum level, accompanied by the changes in the levels of fractalkine and its unique receptor CX3CR1 protein. After transplantation of NSCs on P7d into the subretinal space of rd1 mice, the activated microglia were inhibited and the degeneration of ONL was delayed. In addition, microglia activation was suppressed by co-cultured NSCs in vitro. The gene and protein level of tissue inhibitor of metalloproteinase (TIMP 1) in NSCs was elevated, whereas that of matrix metalloproteinase (MMP9) in BV2 microglia was markedly suppressed in this co-culture system. Conclusions. Transplanted NSCs in the retina exerted immunomodulatory effects on microglia, thus delaying the degeneration of photoreceptors.