Figure 4

The characteristic and anatomic distribution of PD-1 ligands, PD-L1 and PD-L2, in uteri from 2-year old WT mice was detected by immunohistochemistry. (A) Mouse IgG1 isotype control antibodies showed no positive staining; (B) PD-L1 positive cells were observed in the glandular/luminal epithelium; (C) PD-L1 positive cells were observed in the endothelium and cells infiltrated stroma; (D) The PD-L2 expression was absent in blood capillary; (E) The PD-L2 positive cells were observed in the glandular/luminal epithelium; and (F) PD-L2 positive cells were observed infiltrating the stroma. ▲ indicates the glandular epithelium; *indicates the luminal cavity; ◆ indicated blood capillary. The arrows indicate positive endothelial cells and arrow head showed infiltrated cells that are positive for PD-L1 or PD-L2. Scale bar = 20 μm. N = 4 of each group.