Since the reversal of exhausted immunophenotype in PD-1+CD8+ T cell is main mechanism of PD-1/PD-L1 blockade in anti-tumor immunotherapy, we observed the effect of BTLA on reversal of PD-1+CD8+ T cell exhaustion under PD-1/PD-L1 blockade. This evidence concerns the gene PDCD1 and neoplasm.