title: Enhanced production of hepatitis B surface antigen in NIH 3T3 mouse fibroblasts by using extrachromosomally replicating bovine papillomavirus vector.
abstract: We have constructed a recombinant pBR322 plasmid composed of a subgenomic transforming fragment of bovine papillomavirus DNA and the hepatitis B surface antigen gene from cloned hepatitis B virus DNA and used it for transfection of NIH 3T3 mouse fibroblasts. The transformed cells retain the plasmids in extrachromosomal form with a copy number of about 50 to 100 per cell. Expression of the hepatitis B surface antigen gene linked to bovine papillomavirus DNA is independent of its orientation relative to the bovine papillomavirus vector. Cell lines continuously secreting high amounts of hepatitis B surface antigen into the medium could be established. The antigen is released into the culture medium as 22-nm particles, having the same physical properties and constituent polypeptides as those found in the serum of hepatitis B virus-infected patients.
mesh_terms: D000818:Animals; D052688:Bovine papillomavirus 1 / Q000235:genetics; D002460:Cell Line; D003001:Cloning, Molecular; D004274:DNA, Recombinant; D005111:Extrachromosomal Inheritance; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D051379:Mice; D014170:Transformation, Genetic
chemical_list: D004274:DNA, Recombinant; D006514:Hepatitis B Surface Antigens