ApoAⅡ单克隆抗体对抗原决定簇的测定及应用研究

Study on the assay and application of antigenic determinants by ApoAⅡ monoclonal antibodies

目的 研究载脂蛋白AⅡ (ApoAⅡ )单克隆抗体 (McAb)对其抗原的决定簇。方法 应用淋巴细胞杂交瘤技术 ,建立抗人ApoAⅡ杂交瘤细胞株 (BI1 ,BI2 ,BI3,BI4 ,BI5,BI6 ,BI7) ,以制备的McAb用双向免疫扩散法和ELISA对其免疫学特性进行了测定 ,用单抗相加试验和双抗体竞争试验对其抗原决定簇进行分析。结果 Ig亚类测定 :BI1 、BI2 、BI5和BI7为IgG1 ,而BI3、BI4 和BI6 均为IgG2b,腹水效价BI1与BI6 为 1× 10 - 6 ,BI2 、BI3、BI4 、BI5和BI7均达到 1× 10 - 5。特异性测定 :与载脂蛋白AⅠ、B、CⅠ、CⅡ、CⅢ、E、脂蛋白 (a)、人血清白蛋白及纤维蛋白溶酶原 (pg)没有交叉反应。单抗相加试验和双抗体竞争试验结果证实 ,BI1 、BI4 和BI5为识别apoAⅡ上同一抗原决定簇的McAb、BI2 、BI3、BI6 和BI7则为针对apoAⅡ上另一抗原决定簇的McAb。

Objective To study the antigenic determinants of ApoAⅡ monoclonal antibodies (McAbs).Methods Seven antihuman ApoAⅡ hybridoma cell strains (BI 1,BI 2,BI 3,BI 4,BI 5,BI 6 and BI 7) were established by lymphocyte hybridoma technique.The immunological characteristics of McAbs were determined with double immunodiffusion method and ELISA,the antigenic determinants were analyzed with cotitration test and double antibody competitive test.Results The subclass determination of Ig:BI 1,BI 2,BI 5 and BI 7 were IgG 1,BI 3,BI 4 and BI 6 were IgG 2b .The antibody titers of ascitic fluids:BI 1 and BI 6 were 1×10 -6 ;BI 2,BI 3,BI 4,BI 5 and BI 7 were 1×10 -5 .The antibody specificity determination:ApoAⅡ McAbs had not cross reaction with ApoAⅠ,B,CⅠ,CⅡ,CⅢ,E,(a),human serum albumin and plasminogen.The results of cotitration test and double antibody competitive test showed that BI 1,BI 4 and BI 5 were McAbs recognizing the same antigen determinants and BI 2,BI 3,BI 6 and BI 7were McAbs recognizing another antigenic determinants on ApoAⅡ.Conclusion The assay of antigenic determinats by ApoAⅡ monoclonal antibodies provides the theoretical basis for forecasting the risk of atherosclerosis.