用dEXTrAnT40为中介体的方法交联抗人肺腺癌单抗3d3和平阳霉素（A5），每克分子抗体可携带68克分子的药物，交联物中抗体活性仍能达到10-4水平，能较好地与靶细胞l-342结合。体外细胞毒实验，显示交联物和游离A5对靶细胞50%杀伤浓度分别为0.9μMOl/l和4.6μMOl/l，杀伤效果比游离A5强5倍多。单抗对靶细胞几乎没有杀伤作用；无关抗体交联物的作用也很弱。交联物和游离A5对非靶细胞MgC-803的杀伤作用无明显差别。结果提示MCAb3d3具有良好的导向作用，能携带结合的A5特异地杀伤肺腺癌l-342细胞，可作为临床抗肿瘤药物导向治疗的一种载体。The conjugate of pingyangmycin (A5) and monclonal antibody3D3(MCAb3D3) against human lung cancer was prepared with dextran T40 as the mediator.The molar ratio of A5 McAb3D3 in the conjugate was 68:1 the titer of the conjugate was remained at 10-4.In vitro,the cytotoxicity of the conjugate and Free A5 yieded IC50 of 0.9μmol/L and 4.6μmol/L,respectivel.The conjugate was Fivetimes stronger than Free A5 The cytotoxicity of the conjugate on non-target cells MGc-803 was much weaker and similar to that of.Free A5.There is no doubt that MCAb3D3 had targeting activity and could kill or damage tumor cells speciFically and could be taken as a kind of vector in studies of clinical targeting therapy
