C3d及荷C3d免疫复合物的测定与意义

DETECTION OF C3d AND C3d BEARING IMMUNE COMPLEXES AND ITS CLINICAL SIGNIFICANCE

用抗人Ｃ３和抗人ＩｇＧγ球蛋白组分作为固相反应物，建立了检测补体活化片段Ｃ３ｄ及荷Ｃ３ｄ－ＩＣ的ＥＬＩＳＡ法，并对临床各类疾病患者血清Ｃ３ｄ和Ｃ３ｄ－ＩＣ的水平进行了测定。结果表明：慢性肾炎、ＳＬＥ、慢性乙肝及肺炎患者血清Ｃ３ｄ总体水平均较对照组显著增高，分别有５８．５％～７２．２％的病人Ｃ３ｄ含量高于正常上限（Ｐ＜０．０１），且该类病人亦有较高的Ｃ３ｄ－ＩＣ阳性检出率（肺炎患者例外）。本项研究中，Ｃ３ｄ－ＩＣ阳性者，其血清Ｃ３ｄ含量均高于正常水平，提示该类免疫复合物与补体的起始激活有直接关系，因此Ｃ３ｄ－ＩＣ与Ｃ３ｄ可以看作是疾病时组织损伤及补体活化反映的重要参考指标。

Using anti human C3 and anti human IgGγ globulin as solid phase reagents,we established enzyme linked immunosorbent assay(ELISA)technique for C3d fragment production and C3d bearing immune complexes(C3d IC),and measured the serum levels of C3d as well as C3d IC in patients with variety of clinical diseases.The results indicated that total levels of sera C3d were significantly elevated than that of control in of chronic nephritis,SLE,chronic HBV hepatitis and pneumonia patients,it was 58.5%～72.2% of patients that sera C3d concentrations exceeded the upper limit of normal respectively( P <0.01),and the positive rate of C3d IC in these patients was also higher than that in control(except pneumonia).In this study,all the C3d IC positive cases had a higher level of C3d.It was suggested that C3d IC was directly related to the activation of complement cascade.Therefore,C3d IC and C3d could serve as important index to aid of diseases tissue damage as well as activation of complement reflection.