抗人DAF单克隆抗体的制备及鉴定

PREPARATION AND IDENTIFICATION OF McAbs AGAINST HUMAN DECAY ACCELERATING FACTOR

以初步纯化的人红细胞膜ＤＡＦ免疫Ｂａｌｂ／ｃ小鼠，取免疫小鼠脾细胞与ＳＰ２／０骨髓瘤细胞融合，成功地获得３株（ＤＧ３、ＤＧ９和ＤＡ１１）抗人ＤＡＦ单克隆抗体。经间接ＥＬＩＳＡ测定，３株杂交瘤细胞培养上清及腹水的抗体效价分别为１０－３～１０－４及１０－６～１０－７；３株单抗的重链为小鼠ＩｇＧ１亚类，轻链为κ型。结合还原条件下的免疫印迹实验及３株单抗对ＤＡＦ促衰变活性的抑制作用，推测ＤＧ９识别的抗原表位为ＳＣＲ１，而ＤＧ３和ＤＡ１１为ＳＣＲ２至ＳＣＲ４。

Three monoclonal antibodies(McAbs),designate DG3、DG9 and DA11,were prepared against human decay accelerationg factor (DAF,CD55)by fusing myeloma cell line SP2/0 and Balb/c murine spleen cells which had been immunized by partly purified human DAF.The titers of specific antibody in culture supernatants and ascites fluid were 10 -3 ～10 -4 and 10 -6 ～10 -7 respectively by indirect ELISA.All of three McAbs were IgG1 kappa isotypes.Results from Western Blotting using reducing agent and the effects of McAbs on the decay accelerating activity of DAF suggest DG9 reacts to SCR1 of DAF,while the epitope recognized by DG3 and DG9 reside within SCR2～4.