抗癌胚抗原单克隆抗体的制备和初步应用

Development and Application of Monoclonal Antibody Against CEA

[目的]生产抗癌胚抗原(CEA)的单克隆抗体(McAb),制备检测血清CEA含量的酶联免疫吸附分析(ELISA)试剂盒。[方法]用亲和层析法纯化的CEA抗原免疫BALB/C小鼠,经细胞融合挑选出两株适用于CEAELISA试剂盒的McAbs进行重点鉴定。用ELISA法测定亲和力常数和免疫球蛋白亚类,用中和抑制法和免疫印迹电泳法鉴定特异性。[结果]两株McAbs均为鼠IgG1亚类,其亲和力常数分别为1.03×10-9M和2.25×10-9M,只有CEA阳性血清能抑制McAbs与包被CEA的反应,免疫印迹电泳显示两株McAbs只与200kDa的CEA形成一条带,所组成的试剂盒与放射免疫分析试剂盒比较,其灵敏度为96.60%,特异性为99.11%,总符合率为98.52%。[结论]两株McAbs具有较好的特异性和亲和力,用该两株McAbs组成的ELISA试剂盒可以应用于临床检测CEA。

To produce monoclonal antibody against CEA and establish ELISA kit for CEA.Hybridoma lines were obtained by fusing myeloma and spleen cells from immuned BALB/C mouse with CEA purified by affinity chromatography.The affinity constant and isotype of the McAbs were determined with ELISA.The specificity was identified by competitive inhibition and western blotting.We selected two McAbs to establish ELISA kit,and analysed the sensitivity and specificity of ElTSA Kit compared with RIA kit.Two McAbs were mouse IgG 1.Affin-ity constants were1.03×10 -9 M and2.25×10 -9 M respectively.Only serum with positive CEA could inhibit the reaction between McAbs and CEA.It was shown that only2McAbs could produce one band at200kDa region by western blot.The sensitivity,specificity and overall agreement of ELISA kit are96.60%,99.11%and98.52%,respectively.[Conclusion]The two McAbs reveal high specificity and high affinity.ELISA kit made up of these2McAbs may be used for clinical CEA detection.