Combination bortezomib and Mapatumamab therapy induce synergistic death of the human myeloma cell line RPMI8226. A dose response study for (A) bortezomib (B) Mapatumamab was performed on RPMI8226 cells by treating the cells with titrated doses of the monotherapy for 48 hours in triplicate wells. Subsequently RPMI8226 cells were treated with combination bortezomib and Mapatumamab therapy (C). Bortezomib dose (1nM) did not induce apoptosis above untreated controls, Mp was added at doses from 0.03 to 0.15ug/ml. A statistical comparison was made between apoptosis with Mp monotherapy versus Bz plus Mp using student t-test, * represents data points where combination therapy is statistically different to Mp alone, p<0.05. Results are representative of two separate experiments.