title: Expression of costimulatory molecules B7-1 (CD80) and B7-2 (CD86) on human hepatocellular carcinoma.
abstract: Costimulation mediated by costimulatory molecules, such as B7-1 and B7-2, which are ligands for the CD28/cytolytic T lymphocyte associated antigen (CTLA)-4 counter-receptor, plays an important role in the induction of T cell-mediated antitumor immunity. We investigated the expressions of B7-1, B7-2, and human leukocyte antigen (HLA) class I in seven human hepatocellular carcinoma (HCC) cell lines by reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometric analysis. RT-PCR showed that all these human HCC cell lines were positive for B7-1 and B7-2 at the messenger RNA (mRNA) level. Flow cytometric analysis revealed that they all expressed B7-1, B7-2, and HLA class I on the cell surface. However, the expression levels of B7-1 and B7-2 were very low whereas those of HLA class I were high. B7-1 and B7-2 expression could be increased by treatment with interferon alpha and interferon gamma in a dose-dependent manner, although the expression levels of B7-1 and B7-2 after interferon treatment remained low. By transfecting Hep3B cells with a plasmid containing human B7-1 complementary cDNA (cDNA), we were able to establish Hep3B cell lines strongly expressing B7-1. From mixed lymphocytes and tumor cultures analysis, the primary cytolytic activity against parental Hep3B cells could be induced effectively by B71-transfected Hep3B cells. These findings suggested that B7-1 gene transfer is the best way to induce strong expression of this molecule and this might be useful for immuno-gene therapy against human HCC.
authors.affiliation: First Department of Medicine, Osaka University School of Medicine, Suita, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tatsumi
authors.forename: T
authors.initials: T
authors.lastname: Takehara
authors.forename: K
authors.initials: K
authors.lastname: Katayama
authors.forename: K
authors.initials: K
authors.lastname: Mochizuki
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Kanto
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaki
authors.forename: A
authors.initials: A
authors.lastname: Kasahara
authors.forename: N
authors.initials: N
authors.lastname: Hayashi
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis*; D018122:B7-1 Antigen / Q000096:biosynthesis*; D051940:B7-2 Antigen; D006528:Carcinoma, Hepatocellular / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D016133:Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; C497964:CD86 protein, human; D008562:Membrane Glycoproteins