Fei Shuang, Gui Zeping, Feng Dengyuan, Wang Zijie, Zheng Ming, Chen Hao, Sun Li, Tao Jun, Han Zhijian, Ju Xiaobing, Gu Min, Tan Ruoyun, Li Xinli
Department of Urology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
Department of Urology, The Second Affiliated Hospital with Nanjing Medical University, Nanjing, China.
Front Genet. 2022 Feb 21;12:798001. doi: 10.3389/fgene.2021.798001. eCollection 2021.
The occurrence of proteinuria is one of the evaluation indicators of transplanted kidney damage and becomes an independent risk factor for poor prognosis after kidney transplantation. Our research sought to understand these potential associations and detect the underlying impact of single-nucleotide polymorphisms (SNPs) on proteinuria in kidney transplant recipients. There were 200 recipients enrolled in this study, from which blood samples were extracted for SNP mutation-related gene detection. RNA sequencing was performed in kidney tissues after kidney transplantation, and the significantly differentially expressed genes (DEGs) were analyzed between the control group and the proteinuria group. Then, the intersection of genes with SNP mutations and DEGs was conducted to obtain the target genes. Multiple genetic models were used to investigate the relationship between SNPs and proteinuria. In addition, the effect of SNP mutation in the target gene was further validated in human renal podocytes. According to the sequencing results, 26 significant SNP mutated genes and 532 DEGs were found associated with proteinuria after kidney transplantation. The intersection of SNP mutated genes and DEGs showed that the Toll-like receptor 2 (TLR2) gene was significantly increased in the transplanted renal tissues of patients with proteinuria after kidney transplantation, which was consistent with the results of immunohistochemical staining. Further inheritance model results confirmed that mutations at rs3804099 of the TLR2 gene had significant influence on the occurrence of proteinuria after kidney transplantation. In the validation, we found that, after the mutation of rs3804099 on the TLR2 gene, the protein expressions of podocalyxin and nephrin in podocytes were significantly decreased, while the protein expressions of desmin and apoptosis markers were significantly increased. The results of flow cytometry also showed that the mutation of rs3804099 on the TLR2 gene significantly increased the apoptotic rate of podocytes. Our study suggested that the mutation of rs3804099 on the TLR2 gene was significantly related to the generation of proteinuria after kidney transplantation. Our data provide insights into the prediction of proteinuria and may imply potential individualized therapy for patients after kidney transplantation.
蛋白尿的出现是移植肾损伤的评估指标之一，并且成为肾移植后预后不良的独立危险因素。我们的研究旨在了解这些潜在关联，并检测单核苷酸多态性（SNP）对肾移植受者蛋白尿的潜在影响。本研究纳入了200名受者，从中提取血样进行SNP突变相关基因检测。肾移植后对肾组织进行RNA测序，并分析对照组和蛋白尿组之间显著差异表达的基因（DEG）。然后，对具有SNP突变的基因和DEG进行交集分析以获得靶基因。使用多种遗传模型研究SNP与蛋白尿之间的关系。此外，在人肾足细胞中进一步验证靶基因中SNP突变的作用。根据测序结果，发现26个显著的SNP突变基因和532个DEG与肾移植后蛋白尿相关。SNP突变基因与DEG的交集显示，肾移植后蛋白尿患者移植肾组织中Toll样受体2（TLR2）基因显著增加，这与免疫组织化学染色结果一致。进一步的遗传模型结果证实，TLR2基因rs3804099处的突变对肾移植后蛋白尿的发生有显著影响。在验证中，我们发现，TLR2基因上的rs3804099突变后，足细胞中足细胞标记蛋白和nephrin的蛋白表达显著降低，而结蛋白和凋亡标志物的蛋白表达显著增加。流式细胞术结果也显示，TLR2基因上的rs3804099突变显著增加了足细胞的凋亡率。我们的研究表明，TLR2基因上的rs3804099突变与肾移植后蛋白尿的产生显著相关。我们的数据为蛋白尿的预测提供了见解，并可能暗示肾移植后患者潜在的个体化治疗。
