title: Marek's disease virus VP22 enhances potentially the immune response of ESAT-6/CFP-10 against Mycobacterium bovis infection.
abstract: Currently available vaccines against Mycobacterium bovis, the causative agent of tuberculosis, do not provide reliable efficacy and there is therefore a need for a novel vaccine with improved efficacy. Here, we use protein transduction technology to deliver DNA vaccines expressing mycobacterial antigens directly to target cells. We used various protein transduction domain (PTD) proteins including the VP22 conjugate from Marek's disease virus serotype 1 (MDV-1), as delivery systems for DNA constructs encoding the antigens early secretory antigenic target-6 kDa (ESAT-6) protein and culture filtrate protein 10 (CFP-10) of M. bovis. The eukaryotic expression plasmid pZ106, encoding antigens ESAT-6 and CFP-10, conjugated to various PTDs, was used to construct experimental preparations. Our findings demonstrated that VP22 alone or in combination with CFP-10:ESAT-6 fusion protein could spread into all the nuclei of the cell monolayer surrounding the transfected cells. Whereas trans-activating transcriptional PTD showed limited delivery of the fusion protein and 8R peptide was unable to deliver the fusion protein into any untransfected cells. We have demonstrated that immunization with a preparation fused to VP22 leads to a higher antibody and interferon-gamma titer (P<0.05). Taken together, our results demonstrated that MDV-1 VP22 serves as a potential immune enhancer in gene therapy and immunization using DNA vaccines, offering a novel approach for the prevention of M. bovis infection.
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Cuiping
authors.initials: C
authors.lastname: Song
authors.forename: Shengqing
authors.initials: S
authors.lastname: Yu
authors.forename: Chan
authors.initials: C
authors.lastname: Ding
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology; D019411:Clinical Laboratory Techniques; D005260:Female; D055633:Immune System Phenomena / Q000187:drug effects*; D007371:Interferon-gamma / Q000494:pharmacology; D008380:Marek Disease / Q000821:virology*; D051379:Mice; D009164:Mycobacterium Infections / Q000276:immunology*; D009163:Mycobacterium bovis; D009169:Mycobacterium tuberculosis / Q000737:chemistry / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D012106:Research; D014397:Tuberculosis, Pulmonary / Q000517:prevention & control; D019444:Vaccines, DNA; D014764:Viral Proteins / Q000494:pharmacology*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C093276:ESAT-6 protein, Mycobacterium tuberculosis; C505464:ESAT-6-CFP10 fusion protein; D011993:Recombinant Fusion Proteins; C450446:UL49 protein, Marek's disease virus type 1; D019444:Vaccines, DNA; D014764:Viral Proteins; D007371:Interferon-gamma