title: Augmented humoral and cellular immune responses of a hepatitis B DNA vaccine encoding HBsAg by protein boosting.
abstract: Several reports have indicated that combinatorial regimens with DNA and protein vaccines can elicit both strong immune responses, to circumvent the limits of each vaccine. Surprisingly little was known on HBV vaccine. Here, we investigated the immunization effects of several regimens in BALB/c mice. The level of total antibody and isotypes of IgG were determined by ELISA. Cellular immune responses were assayed by measuring the production of cytokines and CTL activity after re-stimulation for 7 days in vitro with tumor cells CT26/S stably expressing HBsAg. The efficacy of immunoprotection against the challenge of transplanted CT26/S was also examined. The regimen involving twice priming pVAX(S) encoding HBsAg and once recombinant HBsAg protein (rHBsAg) boosting, induced strong and homogenous antibody responses. This regimen induced significant stronger responses of interleukin-12 and gamma interferon (IFN-gamma) in splenocytes, and elicited stronger CD8+ CTL responses and greater immunopretectional efficacy than those elicited by immunization with rHBsAg or pVAX(S) alone. Our regimen may thus provide a strategy for developing an improved immunization against HBV and many other pathogens.
authors.affiliation: Department of Medical Genetics, Second Military Medical University, Yangpu district, 200433 Shanghai, China. dr_hxw@msn.com
authors.forename: He
authors.initials: H
authors.lastname: Xiao-wen
authors.forename: Sun
authors.initials: S
authors.lastname: Shu-han
authors.forename: Hu
authors.initials: H
authors.lastname: Zhen-lin
authors.forename: Li
authors.initials: L
authors.lastname: Jun
authors.forename: Jiang
authors.initials: J
authors.lastname: Lei
authors.forename: Zhou
authors.initials: Z
authors.lastname: Feng-juan
authors.forename: Zhang
authors.initials: Z
authors.lastname: Ya-nan
authors.forename: Guo
authors.initials: G
authors.lastname: Ying-jun
mesh_terms: D000276:Adjuvants, Immunologic / Q000235:genetics / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000917:Antibody Formation / Q000235:genetics / Q000276:immunology; D019556:COS Cells; D002522:Chlorocebus aethiops; D004279:DNA, Viral / Q000276:immunology*; D006509:Hepatitis B / Q000276:immunology* / Q000517:prevention & control; D006514:Hepatitis B Surface Antigens / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000276:immunology* / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007111:Immunity, Cellular / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D014162:Transfection; D017778:Vaccines, Combined / Q000276:immunology / Q000494:pharmacology / Q000627:therapeutic use; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D017778:Vaccines, Combined; D014764:Viral Proteins