FCM
To detect the proportion of CD15+LOX-1+ PMN-MDSCs in PB of NSCLC patients and HC, ACK buffer was used to lyse RBCs, and the remaining cells were stained with PE/Cy5.5-anti-human-CD11b (eBioscience, 0.25μg/1×106 cells), APC-anti-human-CD33 (eBioscience, 0.25μg/1×106 cells), PE-anti-human-LOX-1 (eBioscience, 0.25μg/1×106 cells) and FITC-anti-human-CD15 mAbs (eBioscience, 0.25μg/1×106 cells) at 4ºC for 30 min. FCM was performed using a FACSCalibur flow cytometer (Becton Dickinson). Data were analyzed by FlowJo software.