BTLA and neoplasm: The mice undergoing chemotherapy combined with anti-BTLA Ab 20 μg/mouse (G6: paclitaxel 6 mg/kg and anti-BTLA Ab 20 μg/mouse, 1.63 ± 0.04 × 107) exhibited the least luminescence 35 days after tumor inoculation (G1: PBS-treated group, 1.04 ± 0.07 × 108; G2: paclitaxel 6 mg/kg, 7.44 ± 0.25 × 107; G3: anti-BTLA Ab 10 μg/mouse, 7.21 ± 0.18 × 107; G4: anti-BTLA Ab 20 μg/mouse, 6.67 ± 0.17 × 107; G5: paclitaxel 6 mg/kg and anti-BTLA Ab 10 μg/mouse, 2.82 ± 0.19 × 107; p < 0.001, Kruskal-Wallis test, Fig. 1c).