title: [Construction of bicistronic vector and its application to combined DNA vaccine].
abstract: BACKGROUND
  To study preparation of polyvalent DNA vaccine and the control of multiple gene expression.
  
  
  METHODS
  A bicistronic vector pcDNA3.0BA was constructed from pcDNA3.0. HCV PC154 gene and HBV preS2S gene were inserted into this vector to form bicistronic expression construct pcDNA3.0BAPC154S2S and monocistronic expression construct pcDNA3.0BAPC154 or pcDNA3.0BAS2S. These plasmids were transiently expressed in COS-7 cells and injected into muscles of BALB/c mice.
  
  
  RESULTS
  pcDNA3.0BA contains two cistronic units, which can co-express two kinds of genes, with the first immunogen gene and the second gene serving as additional immunogen or as modulator for the immune responses. HBV surface Ag and HCV core Ag were coexpressed in vitro. The antibody responses and lymphoproliferation to antigens were similar between bicistronic and monocistronic expression construct in mice.
  
  
  CONCLUSIONS
  pcDNA3.0BA is a novel vector, which can coexpress two proteins and elicit polyvalent immune responses.
authors.affiliation: Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming 650118, China.
authors.forename: Guo-yang
authors.initials: GY
authors.lastname: Liao
authors.forename: Sheng-li
authors.initials: SL
authors.lastname: Bi
authors.forename: Jian-yong
authors.initials: JY
authors.lastname: Yang
authors.forename: Wei-dong
authors.initials: WD
authors.lastname: Li
authors.forename: Jun-ying
authors.initials: JY
authors.lastname: Chen
authors.forename: Xin-wen
authors.initials: XW
authors.lastname: Zhang
authors.forename: Shu-de
authors.initials: SD
authors.lastname: Jiang
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D004274:DNA, Recombinant / Q000276:immunology; D015870:Gene Expression; D006509:Hepatitis B / Q000097:blood / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000235:genetics / Q000276:immunology*; D006526:Hepatitis C / Q000097:blood / Q000276:immunology; D018937:Hepatitis C Antibodies / Q000097:blood; D018936:Hepatitis C Antigens / Q000235:genetics / Q000276:immunology*; D007114:Immunization / Q000379:methods; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000235:genetics; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*; D014761:Viral Hepatitis Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D004274:DNA, Recombinant; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies; D018936:Hepatitis C Antigens; D019444:Vaccines, DNA; D014761:Viral Hepatitis Vaccines