Multiplexed immunofluorescence
Leica Bond RX was used for multiplex immunofluorescence staining according to the manufacturer’s instructions. The following primary antibodies were used for immunostaining: anti-CD4 (Ventana, SP35, 1:100), anti-CD8 (Ventana, SP57, 1:400), and anti-PD-L1 (Ventana, SP263, 1:250) antibodies. We used 4′,6-diamidino-2-phenylindole (Sigma) to stain the nuclei.