Figure 7.

Antigen specificity of the bispecific antibody product (3). (A) Bispecific antibody (BiAb) highlighting the isotypes of the mAb of each respective arm. (B) ELISA analysis of BiAb binding to plastic immobilized recombinant human MLC1. MLC1 was immobilized at 10 μg/mL. After blocking with BSA, primary antibody was added at a concentration of 10 μg/mL. In the case of “excess MLM508,” unmodified MLM508 was added to the ELISA wells (20 μg/mL) 0.5 h before adding primary antibody. HRP-conjugated secondary antibody specific for IgG1 (the isotype of 5E10) was used for detection. Data are presented as average A₄₅₀ ± SD from triplicate wells. One of three representative experiments is shown. (C) BiAb binding to pig BMMSCs as detected with anti IgG2a-FITC. To demonstrate specific BiAb binding, BMMSCs were pretreated with saturating levels of unlabeled mAb 5E10 (10 μg/mL) for 1 h before adding BiAb. Histograms are representative of three experiments.