Expression Characteristics of Surface Markers of Memory T cells, CD45RO, CCR7 and CD62L, in Tumor-infiltrating Lymphocytes in Liver Cancer Tissues of Patients with Hepatocellular Carcinomas

Abstract

Purposes: To investigate expression of surface markers on memory T cells and distribution of T cell subsets among tumor-infiltrating lymphocytes (TILs) in liver of hepatocellular-carcinoma (HCC) patients. Methods: TILs from liver tumor and paracancerous tissue (PT) of 30 HCC patients and 30 subjects who were performed hepatectomy due to benign pathogenic lesion (control) were stained with anti-CD3, CD4, CD8, CD45RO, CD62L and CCR7 antibodies. The distribution of four T cell subsets, CD45RO+CD62L+CCR7+T (central memory T cells, TCM), CD45RO+CD62L-CCR7-T (effector memory T cells, TEM), CD45RO+ CD62L+CCR7-T (CCR7-T) and CD45RO+ CD62L-CCR7+T (CCR7+T), among TILs was measured with polychromatic flow cytometry and analyzed statistically. Results: (1) CD4+TCM subset in three groups accounted for <0.4% of total CD4+CD45RO+Tm. CD4+TEM subset% in HCC, PT and control was 89.73%, 98.68% and 95.45% of CD4+CD45RO+Tm,which was significantly lower in HCC than in PT and control. CCR7-T subset% in HCC, PT and control was 0.04, 0.46 and 2.44% of CD4+CD45RO+Tm, which was significantly lower in HCC and PT than in control. CCR7+T subset% in HCC, PT and control group was 9.97%, 0.57% and 1.74% of CD4+CD45RO+Tm, which was significantly higher in HCC than in PT and control. (2) CD8+TCM subset% in HCC, PT and control was 0.41%, 0.55% and 0.26% of CD8+CD45RO+Tm, which was significantly higher in HCC and PT than in control. CD8+TEM subset% in HCC, PT and control was 92.39%, 98.14% and 98.16% of CD8+CD45RO+Tm, which was significantly lower in HCC than in PT and control. CCR7-T subset% in HCC, PT and control was 6.44%, 1.03% and 0.75 % of CD8+CD45RO+Tm which was significantly higher in HCC than in PT and control. Conclusion: TEM was the major subset among CD45RO+Tm of HCC patients. CD4+TEM, CD8+TEM and CCR7-T subsets were significantly lower whereas CCR7+T and CCR7+T subsets were significantly higher in tumor than in non-tumor tissues.