Immunostaining of PD-1/PD-Ls in liver tissues of patients with hepatitis and hepatoellulararinoma hepatoellulararinoma

Abstract AIM: To investigate the expression of programmed death (�D)-1, �D ligand 1 (�D-L1) and �D-L2 in liver tissues in the context of chronic hepatitis and hepato-cellular carcinoma (HCC). METHODS: Liver biopsies and HCC specimens from patients were collected and histologically examined. The expression of �D-1, �D-L1, and �D-L2 in biopsy specimens of chronic hepatitis and HCC specimens was evaluated by immunohistochemical staining. The as-sociation between the expression level of �D-1, D-L1, and �D-L2 and clinical and pathological variables was analyzed statistically. RESULTS: Expression of �D-1 was found in liver-infiltrating lymphocytes. In contrast, PD-L1 and PD-L2 were expressed in non-parenchyma liver cells and tumor cells. The expression of PD-L1 was significantly correlated with hepatitis B virus infection (1.42 ± 1.165 vs 0.50 ± 0.756, � = 0.047) and with the stage of HCC (7.50 ± 2.121 vs 1.75 ± 1.500 vs 3.00 ± 0.001, � = 0.018). PD-1 and PD-Ls were significantly up-regulated in HCC specimens (1.40 ± 1.536 vs 5.71 ± 4.051, � = 0.000; 1.05 ± 1.099 vs 4.29 ± 3.885, � = 0.004; 1.80 ± 1.473 vs 3.81 ± 3.400, � = 0.020).