Combined mTim-3 hFc and anti-PDL1 treatment had an additive antitumor effect in an established AML model. B6 mice (10 mice/group) were injected iv with 1 × 106 C1498FFDsR cells. Ten days after AML injection, mice were treated with mTim-3 hFc (100 μg/dose), anti-PD-L1 (200 μg/dose) or combination of both every other day for total of 5 doses. (A) Bioluminescence imaging was performed 14 (not shown), 20 and 27 days post-AML injection (10 mice/group). Mice treated with mTim-3 hFc alone had similar tumor burden to nontreated controls. Anti-PD-L1 mAb single treatment significantly reduced tumor burden on days 14 (not shown) and 20. Mice receiving the combination therapy had decreased tumor burdens at all 3 time points. (B) mTim-3 hFc treatment did not alter the survival of AML-bearing mice. Anti-PD-L1 mAb alone significantly prolonged survival from AML compared with controls (▿ vs ■, P < .01). Combined therapy had superior effect on the survival over either treatment alone (□ vs ▵ and ▿, P < .01). Survival analysis was plotted according to the Kaplan-Meier method, and statistical differences were determined with the log-rank test. Error bar represents SEM.
