Enhanced production of hepatitis B virus surface antigen in mouse C127 cell on a bovine papillomavirus-metallothionein vector.
We have constructed a recombinant plasmid pCPS12 containing the hepatitis B viral surface antigen (HBsAg) gene linked to the mouse metallothionein promoter on a BPV-pML2 vector. Two stable clones S12-8 and S12-2, obtained by transfection of the mouse C127 cells with pCPS12 propagated in dam+ dcm+ and dam- dcm- Escherichia coli respectively, exhibited different types of response to 5-azacytidine (5-aza-CR) and cadmium (Cd) induction. In S12-8, the productivity of HBsAg was enhanced by 5-aza-CR or 5-aza-CR plus Cd, but not by Cd alone. In S12-2, the expression of HBsAg was not affected by 5-aza-CR but was induced by Cd in the presence or absence of 5-aza-CR. This suggests that methylation may be important in controlling the HBsAg expression and the inducibility of Cd in the transfectants.
D000818:Animals; D001374:Azacitidine / Q000494:pharmacology; D002104:Cadmium / Q000494:pharmacology; D019187:Cadmium Compounds; D002460:Cell Line; D004274:DNA, Recombinant; D005822:Genetic Vectors; D006514:Hepatitis B Surface Antigens / Q000235:genetics / Q000302:isolation & purification*; D008668:Metallothionein / Q000235:genetics; D008745:Methylation; D051379:Mice; D027383:Papillomaviridae / Q000235:genetics*; D013431:Sulfates; D014162:Transfection
D019187:Cadmium Compounds; D004274:DNA, Recombinant; D006514:Hepatitis B Surface Antigens; D013431:Sulfates; D002104:Cadmium; D008668:Metallothionein; C037123:cadmium sulfate; D001374:Azacitidine