Preparation and characterization for bispecific antibodies of anti-CD3 x anti-idiotype to B cell lymphocytic leukemia.

Bispecific antibodies (BsAbs) of anti-CD3 x anti-idiotype (Id) to B-cell lymphocytic leukemia (CLL) were prepared by chemical conjugation and direct hybridization technique of hybridoma and hybridoma without screening markers. The specificity of BsAbs from culture supernatants or ascites was assayed by indirect ELISA and indirect immunoflourescence (IF). The results showed that BsAbs could specifically react with homologous serum IgM from patients with B-CLL and cells carrying CD3 marker respectively. Cell combination test and LDH assay demonstrated that BsAb significantly increased the conjugate formation between lymphocyte activated kill (LAK) cells and Daudi cells, and enhanced the cytotoxic activity of LAK cells against Daudi cells.