title: Evaluation of the anti-tuberculosis activity generated by different multigene DNA vaccine constructs.
abstract: Development of multigenic constructs expressing Mycobacterium tuberculosis (Mtb) antigens may be a strategy to obtain improved DNA vaccines against tuberculosis (TB). Several multigenic constructs expressing two or three Mtb antigens as fusion proteins were developed, both as tPA- and ubiquitin-fusion proteins. To demonstrate proper protein expression and intracellular turnover all multiantigens were tagged with the HA epitope and constructs were used to transfect rhabdomyosarcoma (RD) cells. Antigen expression was demonstrated by immunofluorescence using anti-HA antibodies. C57Bl/6 mice were immunized with selected constructs and protective activity was assessed following aerogenic challenge with Mtb. Several of these constructs induced a significant level of protection in the lung and in the spleen. Immunization with the construct expressing tPA85B-ES6 induced a level of protection that approached that provided by BCG. Immunization with a combination of these constructs induced levels of protection that were not superior to those elicited by a single combination, and immunization with a construct expressing five Mtb antigens could not provide an improved level of protection compared to tPA85B-ES6. We conclude that the activity of a DNA vaccine based on tPA85B-ES6 cannot be enhanced by broadening the antigen repertoire with other highly immunogenic secreted Mtb proteins.
authors.affiliation: Institute of Microbiology, Catholic University of the Sacred Heart, Largo A. Gemelli 8, 00168 Rome, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Sali
authors.forename: Sandra
authors.initials: S
authors.lastname: Clarizio
authors.forename: Cinzia
authors.initials: C
authors.lastname: Pusceddu
authors.forename: Antonella
authors.initials: A
authors.lastname: Zumbo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pecorini
authors.forename: Stefano
authors.initials: S
authors.lastname: Rocca
authors.forename: Stefania
authors.initials: S
authors.lastname: Zanetti
authors.forename: Giovanni
authors.initials: G
authors.lastname: Delogu
authors.forename: Giovanni
authors.initials: G
authors.lastname: Fadda
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology; D014376:Tuberculosis / Q000517:prevention & control*; D032581:Tuberculosis Vaccines; D014407:Tumor Cells, Cultured; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*; D014614:Vaccines, Synthetic
chemical_list: D000942:Antigens, Bacterial; D011993:Recombinant Fusion Proteins; D032581:Tuberculosis Vaccines; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic; C072681:Mycobacterium tuberculosis antigens