Table 1.

Sequences of primers used in real-time PCR

Primer	Sequence
	Sense	Antisense
β-actin	5′-AGC TGC GTT TTA CAC CCT TT-3′	5′-AAG CCA TGC CAA TGT TGT CT-3′
PD-1 mouse	5′-TTC AGG TTT ACC ACA AGC TGG-3′	5′-TGA CAA TAG GAA ACC GGG AA-3′
PD-L1 mouse	5′-GCT GAA GT CAA TGC CCC ATA-3′	5′-TCC ACG GAA ATT CTC TGG TTG-3′
PD-L2 mouse	5′-TTG TCG GTG TGA TTG GCT TC-3′	5′-AAA AGG CAG CAC ACA GTT GC-3′