生物人工肾小管对β_2微球蛋白重吸收功能的研究

The Reabsorption of Beta2-Microglobulin by Filtration ThroughBioartificial Renal Tubule Assist Device in Vitro

目的:探讨应用人肾近曲小管上皮细胞株(HK2)构建的生物人工肾小管辅助装置(RAD)体外对β2微球蛋白(β2-MG)的清除作用及机制。方法:A组以HK2体外培养后植入F60血液滤过器内腔构建的RAD后用含β2-MG的置换液体外模拟液体滤过,B组以上述条件构建的RAD用不含β2-MG的置换液模拟液体滤过,C组用含β2-MG的置换液对无细胞植入的F60滤器模拟液体滤过,对各组测定不同时间点的β2-MG滤过率,并应用免疫荧光法观察滤过后A、B组HK2细胞Megalin与β2-MG的蛋白表达。结果:A组β2-MG滤过率在各时间点均明显高于C组(P<0.05);C组β2-MG滤过率在第4h较同组前期各时间点明显降低(P<0.05)。免疫荧光显示A组Megalin与β2-MG同步表达,B组则仅见Megalin表达。结论:以HK2细胞构建的RAD可显著提高β2-MG的滤过率,其功能在4小时内可稳定维持,作用机制可能与Megalin的内吞作用相关。

Objective：To determine the clearance and mechanism of beta2-microglobulin（β2-MG） by using bioartificial renal tubule assist device（RAD） which constructed by HK2 cell line in vitro.Methods：HK2 cells were seeded into the hemofilter（F60） for constructing RAD,then the filtration in vitro was simulated by replacement fluids with β2-MG.RADs of group B were taken the filtration with replacement fluids without β2-MG.The hemofilters without HK2 cell line were uesd in filtration by replacement fluids with β2-MG as group C.The reabsorption rate of three groups were measured.The expression of megalin and β2-MG protein of group A and B were detected by immunofluorescence after filtration.Results：The β2-MG reabsorption rate of group A was significantly higher as compared with group C（P0.05）.The reabsorption rate of β2-MG in group C at the fourth hour of filtration significantly decreased as compared with other time points of group C.Immunofluorescence detection indicated that HK2 cells of group A both have the expression of megalin and β2-MG,meanwhile only the expression of megalin was detected in the cells of group B.Conclusion：The RAD cuntructed by HK2 cell line can obviously increase the reabsorption function of β2-MG.The function could maintain well during 4 hours.The probable mechanism is associated with the endocytosis of megalin.