骨髓间充质干细胞对系膜增生性肾炎的修复作用及机制探讨

Repair of mesangial proliferative glomerular nephritis with mesenchymal stem cells transplantation and its mechanism

目的观察骨髓间充质干细胞(mesenchymal stem cells,MSCs)移植后在大鼠肾脏的分化并研究其对于抗Thy1.1系膜增生性肾小球肾炎的损伤修复作用。方法测定60Coγ照射比较组24 h尿蛋白定量、血清尿素氮及血肌酐水平,观察肾脏病理;注射Thy1.1单克隆抗体建立Thy1.1肾炎模型;分离培养鉴定MSCs,以PKH67标记;观察MSCs移植后Thy1.1肾炎模型组及对照组第24 h尿蛋白量及血Cr水平,肾脏改变及MSCs在肾脏的分布情况;红色荧光标记RECA-1、OX-7、ED-1;测定MSCs培养上清液和对照组VEGF和TGF-β1的浓度;结果60Coγ照射比较组实验指标及肾脏病理无明显差异。Thy1.1肾炎模型组与正常对照组相比,24 h尿蛋白明显升高,80%的大鼠出现镜下血尿,肾病理小球系膜细胞弥漫性增多伴基质增加,肾功能与对照组无差异。MSCs模型移植组24 h尿蛋白量明显减少,病理改变减轻,死亡率降低。肾小球中极少见双重染色细胞。MSCs培养上清液VEGF和TGF-β1的浓度明显升高。结论剂量为8Gy的60Co照射可增加MSCs在肾脏沉积。MSCs移植可参与肾小球的损伤修复,改善系膜增生性肾小球肾炎,其机制可能与旁分泌VEGF和TGF-β1促进修复有关。

Objective To observe the differentiation of transplanted mesenchymal stem cells （MSCs） in rat＇ s kidney and to explore the mechanisms of repair in injury of anti-Thyl. 1 glo- merular nephritis. Methods Twenty-four hours urinary protein quantitative analysis, serum BUN and Cr in 60^Coγ radiation compared groups were measured and kidney pathology was ob- served ; The anti-Thyl. 1 glomerular nephritis models were set up by infusion of Thyl. 1 mono- clonal antibody ; MSCs were isolated, cultured, identified and labeled with PKH67 ; 24h urinary protein quantitative analysis and serum Cr were measured and the distribution of transplanted MSCs in kidney and other changes were observed; RECA-1 ,OX-7,ED-1 were marked with red immunofluorescense staining. The concentration of VEGF and TGF-γ were examined in the cul- ture supernatant and control group. Results The experimental index and kidney pathology had no significant difference in 60Coγ/radiation compared groups. Twenty-four hours urinary protein quantification increased, microscopic hematuria appeared in 80% rats, increased and diffused mesangial cells and matrix were showed in renal pathology, and renal function had no differ- ence in anti-Thyl. 1 glomerular nephritis group compared with the control group. Twenty-four hours urinary protein quantification was decreased obviously, pathologic injury was lightened, and mortality was reduced in MSCs transplanted model. Only a few double-staining cells were detected in glomerulus. The concentration of VEGF and TGFβ1 increased in the culture supernatant. Conclusion 60Coγ radiation with 8Gy might help MSCs aggradation in kidney. MSCs transplantation participats a part in improvement of glomerulus injury, ameliorates anti-Thy1. 1 glomerular nephritis. The mechanisms might be related to paracrine of VEGF and TGFβ1 which could accelerate the repairment of glomerulus.