[Expression of PD-1 and PD-L1 in the peripheral blood of advanced non-small-cell lung cancer patients and its implications].

Abnormal expression of PD-1 and PD-L1 exists in T cells and monocytes respectively, prompting PD-1/PD-L1 pathway may inhibit T cell proliferation during the interaction of T cell and monocyte, which may lead to non-small cell lung cancer immune escape.