[The expression of HLA, Epstein-Barr virus nuclear antigen and the infiltration of T lymphocyte subsets in nasopharyngeal biopsy tissues].

The HLA typing, EBV-EBNA expression and the infiltration of T cell subsets in nasopharyngeal biopsies were investigated using APAAP (Alkaline phosphatase and anti-alkaline phosphatase) and anti-complement immunofluorescence method with a panel of monoclonal antibodies which are W6/32 (anti-HLA-A,B,C), CR3/43 (anti-HLA-DR, DP, DQ), serum from nasopharyngeal carcinoma (NPC, anti-EBNA) and T4, T8, T11(anti-Th, Tc, T3, respectively). There were 25 cases of NPC, 10 of chronic nasopharyngitis (CNP), CNE-2Z cell line and transplants of CNE-2Z, NCN-Z-1 and fetal nasopharynx mucosa under detection. The results showed that the tumor cells of NPC expressed not only HLA-I but also HLA-II. The expression of HLA-II was stronger than that of HLA-I in NPC. The expression of HLA-I and II in epithelial cells of CNP was weak. There was a significant distinction between those groups (P < 0.05). The expression of HLA-I, II was the strongest in CNE-2Z smears and transplants in under mice of CNE-2Z, NCN-Z-1, both negative in fetal nasopharyngeal epithelial transplants. It suggested that HLA express abnormally during carcinogenesis, the cancer cells with HLA-II be not recognized by EBV specific T cells, hence escape from the immune surveillance. Also it demonstrated that the EBNA expression in the cancer cells of NPC was strongly positive, the cells of T3, Th, and Tc in NPC were decreased. It needs further study whether or not the EB virus infection can induce HLA phenotype changes in tumor cells and what the biological functions of HLA-II expression in tumor cells are.