IgA肾病患者补体经典途径在血液及尿液中的活化及与肾损伤的关系

目的 研究循环系统中经典途径补体活化及调节方式在IgA肾病（IgAN）中的致病作用及与肾损伤的关系.方法 IgA肾病组30例,10例狼疮性肾炎（LN）患者作阳性对照,30例健康体检者作对照组.采用ELISA试剂盒检测IgA肾病患者和对照组血及尿液中经典途径补体激活标志物C1q、经典途径调节因子（sCR）1,分析补体浓度与肾组织病理结果及临床生化指标的相关性.将IgA肾病组患者按照病理Lee氏结果进行分组,Lee氏Ⅰ～Ⅲ级定为轻度损伤组,Lee氏Ⅳ～Ⅴ级定为重度损伤组,比较两组间的补体浓度差异.分析血C1q与sCR1间相关性.结果 IgA肾病组患者血清C1q及sCR1水平均高于对照组（P＜0.05）,而IgA肾病组与LN组间比较差异无统计学意义（P ＞0.05）;LN组患者尿液C1q浓度明显高于另外2组（P＜0.01）.当血清肌酐＞ 133μmol/L时,血C1q与肌酐水平呈显著负相关（P＜0.05）.尿C1q与肌酐水平呈显著正相关（P＜0.05）.Lee氏Ⅳ～Ⅴ级组患者血液及尿液C1q均明显低于Lee氏Ⅰ～Ⅲ级组（P＜0.05）.血sCR1与血C1q间呈显著正相关（P＜0.05）.结论 IgA肾病患者循环系统中可能存在补体经典途径激活通路,尤其是在肾损伤严重组,且与疾病的严重程度相关.IgA肾病中可溶型CR1对C1q存在介导调节作用.

Activation of the classical pathway of complement in serum and urine of IgA nephropathy and its association with the kidney injury

Objective To investigate the pathogenesis of IgA nephropathy（IgAN） on the aspect of serum classical pathway of complement activation. Methods Patients were divided into 3 groups, 30 patients with IgAN in as disease group, 10 patients with lupus nephritis （LN） in as positive disease control group and 30 healthynormal adults in were as healthynormal control. The levels of Clq and sCRI （ biomak- ers of complement classical pathway activation and regulation） serum and urine were examined in serum and urine samples were collected to detect the level of Clq and sCR1 which represent biomakers of com- plement classical pathway activation and regulation respectively with commercial ELISA kits. The IgAN group was further analyzed by dividing into two groups according to their Lee＇ s grade. The authors regroup the IgAN patients according to pathological Lees degree, and define Lee＇ s grade I ~III was allocated toas mMinor injury group, and define Lee＇ s grade IV - V was allocated toas severe injury group. Results The levels of complements factor between these three groups were significantly different （ and the statistical P valuep 〈0.05 ,for using K-W test）. The serum level of Clq and sCR1 were higher in IgAN group than thosethat in healthynormal control （ P 〈 0.05 ）. The urine C 1 q level in LN group was significantly higher in LN group than the other two groups（ P 〈 0.01 ）. The serum C lq（ r = -0. 738 ,P = 0.037 ）, as well as the urine C 1 q （ P 〈 0.05 ） was correlated with serum ereatinine （SCr） （ P 〈 0.05 ）, as well as the urine C 1 q （ P 〈 0.05 ）. Patients with higher Lee＇ s grade pathological degree shewed lower serum and urine C1 q levels. The correlation between serum sCRland serum Clq was significantapparent （P 〈 0.05 ）. Conclusion Classical pathway of complement activation of classical pathway may be involved in the pathogenesis of IgAN,especially in more severe casesdamaged group. The soluble form of CR1 might have a role in the regulation.