title: Novel tumor-associated antigen of hepatocellular carcinoma defined by monoclonal antibody E4-65.
abstract: A monoclonal antibody, E4-65, produced by immunizing mice with SMMC-7721 cells, a human hepatocellular carcinoma (HCC) cell line, was used to identify and characterize an unreported HCC-associated antigen. Indirect immunofluorescence studies showed that E4-65 antibody reacted with five out of eight HCC cell lines, but not with 10 non-HCC tumor cell lines or a normal liver cell line. Using immunohistochemical examination, E4-65 antigen was detected on the cell membranes and in the cytoplasm of human liver tumor tissues, but was not found in most other tumors, or normal adult or fetal tissues, except for a weakly positive reaction in tissues of the digestive system. Western blot analysis showed that E4-65 antibody bound to a 45 kDa protein in the human HCC cell line and tissue lysates. Enzyme treatment and lectin blotting did not detect the carbohydrate chain in E4-65 antigen. This HCC-associated protein represents a potentially useful target for diagnoses and immunotherapy of human HCC.
authors.affiliation: Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Zou
authors.forename: Jihang
authors.initials: J
authors.lastname: Ju
authors.forename: Hong
authors.initials: H
authors.lastname: Xie
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry*; D000951:Antigens, Neoplasm / Q000096:biosynthesis* / Q000737:chemistry* / Q000276:immunology; D006528:Carcinoma, Hepatocellular / Q000737:chemistry / Q000276:immunology; D045744:Cell Line, Tumor; D019084:Fluorescent Antibody Technique, Indirect; D018922:HL-60 Cells; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D007167:Immunotherapy / Q000379:methods; D037102:Lectins / Q000737:chemistry; D008099:Liver / Q000378:metabolism; D008113:Liver Neoplasms / Q000737:chemistry / Q000276:immunology*; D009928:Organ Specificity
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D037102:Lectins