Fig. 2From: Development of a human immuno-oncology therapeutic agent targeting HER2: targeted delivery of granzyme BELISA binding of GrB-Fc-4D5 to Her2/ECD. Purified HER2/neu ECD were coated on 96-well ELISA plates. After incubation with the target protein (1 h) and wash steps, human anti-GrB antibody was added and incubated, followed by the addition of horseradish peroxidase-conjugated goat anti-human immunoglobulin antibody. Absorbance at 405 nm was measured after 30 mins. a Various concentrations of either GrB-Fc-4D5 or GrB(S195A)-Fc-4D5 protein to determine Kd of the 4D5 scFv. b Various concentrations of GrB-Fc-4D5 and an unrelated GrB-Fc-scFv (as a specificity control) to confirm specificity of the 4D5 scFv for HER2 ECDBack to article page