Fig. 3
From: Modeling antibody drug conjugate potential using a granzyme B antibody fusion protein
Internalization and apoptosis-inducing effects of GrBmut-TRA. A B16 and B16.HER2 cells were treated with molar equivalents of rGrB, TRA, or GrBmut-TRA before being acid washed, fixed/permeabilized, stained for GrB (green) and nuclei (blue), and assessed by IF. B HER2-expressing and non-expressing cells were treated overnight under various conditions that included TRA, T-DM1, or GrBmut-TRA. Camptothecin was utilized as a positive control for inducing cell death. All cells were collected and stained with reagents detecting caspase 3/7 and dead cells by flow cytometry. Bar graphs indicate the frequency of caspase 3/7 positive events. Representative histogram plots across treatments are also provided. Abbreviations used: GrB, granzyme B; rGrB, recombinant GrB; GrBmut-TRA, catalytically active AFP; Pro-GrBmut-TRA, catalytically inert molecule; T-DM1, ado-trastuzumab emtansine; TRA, trastuzumab. *P < 0.05, bars ± STDEV. Select results are based on technical replicates of 2 samples per treatment group. Individual data values are provided in supplementary information (Additional file 2)