检测抗-HCV IgG κ/λ轻链比值及其临床意义

目的 探讨丙型肝炎病毒(HCV)感染者保护性免疫缺陷的原因。方法 根据HCV C区和NS4区基因序列设计并人工合成3条合成肽。采用抗原捕捉酶联免疫吸附试验检测HCV感染者血清中抗-HCV IgG抗体轻链κ／λ比值。结果 抗-HCV SP42，CP10和CP9抗体轻链的表达呈明显的偏斜；84例抗-HCV阳性者中82例(97．62％)抗-HCV IgG抗体轻链κ／λ比值偏离。所有病例追踪观察一年(其中11例抗-HCV阳性者随访二年)，发现抗-HCV抗体κ／λ比值恒定不变。结论 HCV感染者抗-HCV抗体的产生不均匀性并呈稳定的克隆性。B细胞克隆优势化可能是HCV感染后机体保护性免疫缺陷的原因之一。

Detection of Differences in Light Chain Isotype (κ/λ) Expression of Anti-HCV Antibodies after HCV Infection and Its Clinical Significance

Objective To study the cause of protective immunodeficiency of patients with hepatitis C. Methods An antigen capture ELISA in which HCV synthetic peptides SP42, CP10 and CP9 derived from HCV NS4 and core gene region, respectively, were used as solid-phase antigens was used to detect the differences in light chain isotype expression of anti-HCV antibodies. Results Antibodies in 84 sera of HCV-infected patients against HCV SP42, CP10 and CP9 were characterized by a skewed light chain isotype expression. Eighty-two out of 84 sera of HCV infection (97 62%) showed at least one of the three anti-HCV antibodies skewed from the normal ratio of light chain isotype kappa/lambda. The kappa/lambda ratios of anti-HCV antibodies in all patients with hepatitis C were found to be unique and constant during one year follow-up, and 11 of them received two years follow-up. Conclusions Anti-HCV response was stable and clonally restricted in HCV infection. B-cell clonal dominance may be the cause of human protective immunodeficiency after HCV infection.