三种实验性IgA肾病模型的比较

目的探讨建立一种理想的IgA肾病（IgAN）动物模型方法。方法分别采用葡聚糖G200、大肠杆菌外膜蛋白和金葡菌的细胞膜20肽抗原决定簇诱导小鼠IgA肾病模型。用分子生物学和病理学方法对3组IgAN模型小鼠进行鉴定和比较。结果（1）葡聚糖组尿蛋白增高，伴有血尿；免疫荧光显示部分肾小球大量IgA沉积；光镜下肾小球系膜细胞增多，肝和脾可见弥漫性的粉染物质沉积；电镜下肾小球系膜区少量低电子密度的致密沉积物，肝和脾可见淀粉丝样物质沉积。（2）大肠杆菌外膜蛋白组尿蛋白增高，伴有血尿；免疫荧光显示肾小球有少量IgA沉积；光镜下肾小球系膜细胞轻度增多，间质炎细胞浸润明显；电镜下肾小球系膜区无电子致密沉积物。（3）金葡菌细胞膜20肽抗原决定簇组尿蛋白增高，伴有血尿；免疫荧光显示多数肾小球均可见大量IgA沉积；光镜下肾小球系膜细胞增多，伴系膜基质轻度增生；电镜下肾小球系膜区和基底膜的内皮细胞下可见高电子密度的致密沉积物。结论金葡菌细胞膜20肽抗原决定簇组诱导的IgAN模型从临床表现和病理学变化与人IgAN极其相似，是3种IgAN模型中最理想的IgAN模型。

Comparison of three kinds of experimental IgA nephropathy model

Objective To establish an optimal experimental animal model of IgA nephropathy (IgAN). Methods Three kinds of proteins, Dextran G200, outer membrane proteins (OMPs) of Bacillus coli (E.coli) and 20 peptide cellular antigen determinant of staphylococcus aureus, were used to induce IgAN animal model respectively. Animal models were identified and their clinicopathological features were compared by molecular biological and pathological methods. Results (1) In dextran G200 group, urinary protein elevated obviously accompanied by hematuria; immunofluoresence staining revealed a great quantity of IgA depositing in some glomeruli; light microscopy showed a remarkable proliferation of mesangial cells in kidney and diffuse pink-dyed substance deposition in liver and spleen; electron microscopy demonstrated a low electron dense deposition in glomerular mesangial region and amylonloid material in liver and spleen. (2) In OMPs group, urinary protein elevated obviously accompanied by hematuria; immunofluoresence staining revealed less amount of IgA deposition in glomeruli; light microscopy showed a slight proliferation of mesangial cells and obvious interstitial infiltration of inflammatory cells; no electron dense deposition was found in glomerular mesangial region by electron microscope. (3) In 20 peptide cellular antigen determinant of staphylococcus aureus group, urinary protein elevated obviously accompanied by hematuria as well; immunofluoresence staining revealed a large quantity of IgA deposition in most glomerui; light microscopy showed a slight proliferation of mesangial cells and matrix; electron microscopy demonstrated a high eleotron dense deposition in subendothelial cells and mesangial region. Conclusion The clinicopathological characteristics of IgAN animal model induced by 20 peptide antigen determinant of staphylococcus aureus are similar to human IgAN, which is the best among these three animal models.