title: Detection of hepatitis B virus X product using an open reading frame Escherichia coli expression vector.
abstract: The genome of the hepatitis B virus (HBV) contains a sequence, designated X, capable of encoding a protein of 154 amino acids. To determine whether the putative protein synthesized from this region is antigenic, we examined the sera of HBV-infected patients for the ability to react with a hybrid protein that contained 133 amino acids encoded by the X region and portions of the bacterial ompF and beta-galactosidase genes. Some HBV-positive sera tested contained antibodies that specifically recognized the hybrid protein. All sera were from patients diagnosed as suffering from chronic active hepatitis. We conclude that the X region of HBV encodes a protein and that this protein is antigenic in some patients.
mesh_terms: D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation; D005814:Genes, Viral; D005822:Genetic Vectors; D006511:Hepatitis B Antigens / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics*; D006521:Hepatitis, Chronic / Q000276:immunology / Q000382:microbiology; D006801:Humans; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D006511:Hepatitis B Antigens; D014764:Viral Proteins