中文摘要：

目的研究原发性胆汁性肝硬化（PBC）患者IgG各亚型水平。方法利用免疫散射比浊法检测60例PBC患者及40名健康对照者血清IgGl、IgG2、IgG3和IgG4的浓度，计算总IgG及各亚型占总IgG的百分比。将PBC患者分为初治组、熊去氧胆酸（UDCA）生化应答良好组（经典组）和UDCA应答不良组（难治组）。组间比较用Mann-Whimey U非参数检验方法。结果60例PBC患者血清IgG1、IgG2、IgG3、IgG4的浓度中位数（第5，95百分位数）分别为[9043（8179，9906），6024（5364，6685），996（783，1209），434（331，536）mg／L]。40名健康对照者血清IgGl、IgG2、IgG3、IgC4的浓度分别为[8010（7584，8435），5406（4718，6094），394（320，469），565（431，699）mg／L]。PBC患者血清IgG3、IgG3占总IgG百分比较对照组显著升高（P〈O．01），总IgG较对照组升高（P〈O．05），IgG4及IgG4占总IgG百分比较对照组降低（Pl〈0．05）。PBC初治组、经典组和难治组3组之间IgG亚类及总IgG浓度差异无统计学意义。结论IgG3可能参与PBC的病理过程。PBC患者血清IgG各亚型的水平及总IgG浓度不能作为监测PBC的治疗效果及预后的指标。IgG4水平降低，提示PBC是一类不同于IgG4相关疾病的自身免疫病。

英文摘要：

Objective To investigate the relationship between the variations of IgG subclass concentrations and primary biliary cirrhosis （PBC）. Methods The serum levels of IgG subclass from 60 patients of PBC and 40 healthy controls were determined by immunoephelometric assay. We calculated the total serum IgG levels and the proportion of each IgG subclass to the total IgG. Patients were divided into three groups,initial treatment group, good response to UDCA group and refractory group. Mann-Whitney U test was used for statistical analysis. Results The concentrations of IgG1, IgG2, IgG3 and IgG4 and total IgG in 60 patients with PBC were expressed as median （5th, 95th percentile）as follow： [9043 （8179, 9906）, 6024 （5364, 6685）, 996 （783, 1209）, 434 （331, 536） mg/L]. The corres-ponding concentrations in the control group were [8010（7584, 8435）, 5406（4718, 6094）, 394（320, 469）, 565（431, 699） mg/L]. The median serum IgG3 and percentage of IgG3 were significantly increased in the sera of PBC patients （P〈0.01）, the total IgG increased （P〈0.05）, while the IgG4 and the percentage of IgG4 decreased （P〈0.05）compared to healthy controls. There was no statistical difference in the concentration of each subclass and total IgG among the three groups of PBC. Conclusion The results of this study indicate that there is markedly increase of IgG3 and the percentage of IgG3 during the course of PBC and this reveals the immunopathology of the disease. The concentration of IgG subclass should not be a monitor parameter for PBC. This study also shows that PBC is a kind of autoimmune disease which is different from IgG4 related disease.