Gene expression profiling reveals that BCL-XL correlates with reduced sensitivity CD79b-vcMMAE that can be overcome with ABT-263. (A) BCL-XL (BCL2L1) correlates with reduced anti–CD79b-vcMMAE activity. Red arrow highlights Granta-519 cell line. (B) ABT-263 can add to the activity of anti–CD79b-vcMMAE in a NHL model, Granta-519, with high BCL-XL expression.