title: Fused Mycobacterium tuberculosis multi-stage immunogens with an Fc-delivery system as a promising approach for the development of a tuberculosis vaccine.
abstract: Tuberculosis (TB) remains a major health problem worldwide. Currently, the Bacilli Calmette-Guérin (BCG) is the only available licensed TB vaccine, which has low efficacy in protection against adult pulmonary TB. Therefore, the development of a safe and effective vaccine against TB needs global attention. In the present study, a novel multi-stage subunit vaccine candidate from culture filtrate protein-10 (CFP-10) and heat shock protein X (HspX) of Mycobacterium tuberculosis fused to the Fc domain of mouse IgG2a as a selective delivery system for antigen-presenting cells (APCs) was produced and its immunogenicity assessed. The optimized gene constructs were introduced into pPICZαA expression vectors, and the resultant plasmids (pPICZαA-CFP-10:Hspx:Fcγ2a and pPICZαA-CFP-10:Hspx:His) were transferred into Pichia pastoris by electroporation. The identification of both purified recombinant fusion proteins was evaluated by SDS-PAGE and immunoblotting. Then the immunogenicity of the recombinant proteins with and without BCG was evaluated in BALB/c mice by assessing the level of IFN-γ, IL-12, IL-4, IL-17 and TGF-β cytokines. Both multi-stage vaccines (CFP-10:HspX:Fcγ2a and CFP-10:HspX:His) induced Th1-type cellular responses by producing high level of IFN-γ (272 pg/mL, p<0.001) and IL-12 (191 pg/mL, p<0.001). However, the Fc-tagged recombinant protein induced more effective Th1-type cellular responses with a low level of IL-4 (10 pg/mL) compared to the CFP-10:HspX:His group. The production of IFN-γ to CFP-10:HspX:Fcγ2a was markedly consistent and showed an increasing trend for IL-12 compared with the BCG or CFP-10:HspX:His primed and boosted groups. Findings revealed that CFP-10:Hspx:Fcγ2a fusion protein can elicit strong Th1 antigen-specific immune responses in favor of protective immunity in mice and could provide new insight for introducing an effective multi-stage subunit vaccine against TB.
authors.affiliation: Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Arman
authors.initials: A
authors.lastname: Mosavat
authors.affiliation: Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Saman
authors.initials: S
authors.lastname: Soleimanpour
authors.affiliation: Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Farsiani
authors.affiliation: Department of Laboratory Sciences, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Sadeghian
authors.affiliation: Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Kiarash
authors.initials: K
authors.lastname: Ghazvini
authors.affiliation: Immunobiochemistry Lab, Immunology Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Sankian
authors.affiliation: Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Saeid Amel
authors.initials: SA
authors.lastname: Jamehdar
authors.affiliation: Inflammation and Inflammatory Diseases Research Centre, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: RezaeeR@mums.ac.ir.
authors.forename: Seyed Abdolrahim
authors.initials: SA
authors.lastname: Rezaee
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D000942:Antigens, Bacterial / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D016207:Cytokines / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression; D007114:Immunization; D007141:Immunoglobulin Fc Fragments / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008958:Models, Molecular; D009163:Mycobacterium bovis / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology*; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D014376:Tuberculosis / Q000517:prevention & control*; D032581:Tuberculosis Vaccines / Q000235:genetics / Q000276:immunology*; D022223:Vaccines, Subunit / Q000235:genetics / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; D007141:Immunoglobulin Fc Fragments; D011993:Recombinant Fusion Proteins; D032581:Tuberculosis Vaccines; D022223:Vaccines, Subunit; C072681:Mycobacterium tuberculosis antigens
keywords: CFP-10; Fc-delivery system; HspX; Multi-stage immunogens; Mycobacterium tuberculosis; Subunit vaccine