Guo Wei, Feng Jiang-Min, Yao Li, Sun Li, Zhu Guang-Qing
Department of Nephrology, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
BMC Nephrol. 2014 Jul 9;15:110. doi: 10.1186/1471-2369-15-110.
Therapeutic options in IgAN are still limited. The aim of this study is to explore the feasibility of using endothelial progenitor cell to treat IgAN in rat model.
Rat bone marrow mononuclear cells (BM-MNCs) obtained with density gradient centrifugation were cultured in vitro, and induced into endothelial progenitor cells (EPCs). EPCs were identified by surface marker CD34, CD133 and VEGFR2 (FLK-1) and by Dil-Ac-LDL/FITC-UEA-1 double staining. EPCs were labeled with PKH26 prior to transplantation. Rat model of IgAN was established by oral administration of bovine serum albumin together with lipopolysaccharide via the caudal vein and subcutaneous injection of CCL4. Kidney paraffin sections were stained by H&E and PAS. Immunofluorescence was used to assess IgA deposition in the glomeruli. Peritubular capillary (PTC) density was determined by CD31 staining. Monocyte chemoattrant protein-1 (MCP-1), hypoxia-inducible factor-1α (HIF-1α) and CD105 were also measured by immunohistochemistry, western blotting and real-time fluorescent quantitative PCR.
The transplanted BM-EPCs were successfully located in IgAN rat kidney. After transplantation, Urinary red blood cell, urine protein, BUN, Scr and IgA serum level were significantly decreased, so were the areas of glomerular extracellular matrix and the IgA deposition in the glomeruli. In addition, PTC density was elevated. And the expression levels of HIF-1α and MCP-1 were significantly down-regulated, while the expression of CD105 was up-regulated. All these changes were not observed in control groups.
The BM-EPCs transplantation significantly decreases the expansion of glomerular extracellular matrix and the deposition of IgA in the glomeruli; lowers the expression of inflammatory factors; increases PTC density; improves ischemic-induced renal tissue hypoxia, all of which improves the renal function and slows the progress of IgA nephropathy.
IgA肾病的治疗选择仍然有限。本研究旨在探讨使用内皮祖细胞治疗大鼠IgA肾病模型的可行性。
通过密度梯度离心获得大鼠骨髓单个核细胞（BM-MNCs），并在体外培养，诱导分化为内皮祖细胞（EPCs）。通过表面标志物CD34、CD133和血管内皮生长因子受体2（VEGFR2，即FLK-1）以及Dil-Ac-LDL/FITC-UEA-1双重染色来鉴定EPCs。在移植前用PKH26标记EPCs。通过尾静脉口服牛血清白蛋白和脂多糖以及皮下注射四氯化碳建立大鼠IgA肾病模型。肾脏石蜡切片进行苏木精-伊红（H&E）和过碘酸-雪夫（PAS）染色。采用免疫荧光法评估肾小球中IgA的沉积情况。通过CD31染色测定肾小管周围毛细血管（PTC）密度。还通过免疫组织化学、蛋白质印迹法和实时荧光定量PCR检测单核细胞趋化蛋白-1（MCP-1）、缺氧诱导因子-1α（HIF-1α）和CD105。
移植的骨髓来源EPCs成功定位于IgA肾病大鼠肾脏。移植后，尿红细胞、尿蛋白、血尿素氮（BUN）、血肌酐（Scr）和血清IgA水平显著降低，肾小球细胞外基质面积和肾小球中IgA沉积也显著减少。此外，PTC密度升高。并且HIF-1α和MCP-1的表达水平显著下调，而CD105的表达上调。对照组未观察到这些变化。
骨髓来源EPCs移植显著减少肾小球细胞外基质扩张和肾小球中IgA沉积；降低炎症因子表达；增加PTC密度；改善缺血诱导的肾组织缺氧，所有这些均改善肾功能并减缓IgA肾病的进展。
