title: Development of live attenuated Bordetella pertussis strains expressing the universal influenza vaccine candidate M2e.
abstract: The attenuated Bordetella pertussis BPZE1 vaccine strain represents an attractive platform for the delivery of heterologous vaccine candidates via the nasal route. The filamentous hemagglutinin (FHA) has been used to secrete or expose the foreign antigens at the bacterial surface. In this study, one, two and three copies of the Cys-containing ectodomain of matrix protein 2 (M2e) from influenza A virus were genetically fused to full length FHA and expressed in BPZE1. The secretion efficacy of the FHA-(M2e)(1,2,3) chimera in the extracellular milieu and the ability of the recombinant bacteria to colonize the mouse lungs inversely correlated with the number of M2e copies fused to FHA. Nevertheless FHA-(M2e)(3)-producing bacteria (BPLR3) triggered the highest systemic anti-M2e antibody response upon nasal administration to BALB/c mice. Nasal immunization with BPLR3 bacteria resulted in a significant reduction in the viral loads upon challenge with H1N1/PR8 influenza A virus, but did not improve the survival rate compared to BPZE1-immunized mice. Furthermore, since previous work reported that disulfide bond formation in Cys-containing passenger antigens affects the secretion efficacy of the FHA chimera, the dsbA gene encoding a periplasmic disulfide isomerase was deleted in the FHA-(M2e)(3)-producing strain. Despite improving significantly the secretion efficacy of the FHA-(M2e)(3) chimera, the dsbA deletion did not result in higher anti-M2e antibody titers in mice, due to impaired bacterial fitness and colonization ability.
authors.affiliation: Department of Microbiology, National University of Singapore, CeLS Building #03-05, 28 Medical Drive, 115597 Singapore, Singapore.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.forename: Annabelle
authors.initials: A
authors.lastname: Lim
authors.forename: Stephanie T L
authors.initials: ST
authors.lastname: Ow
authors.forename: Meng Chee
authors.initials: MC
authors.lastname: Phoon
authors.forename: Camille
authors.initials: C
authors.lastname: Locht
authors.forename: Vincent T
authors.initials: VT
authors.lastname: Chow
authors.forename: Sylvie
authors.initials: S
authors.lastname: Alonso
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D001886:Bordetella pertussis / Q000235:genetics*; D004337:Drug Carriers; D005822:Genetic Vectors; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D008168:Lung / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D016019:Survival Analysis; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D019562:Viral Load; D014763:Viral Matrix Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D000086082:Viroporin Proteins
chemical_list: D001428:Bacterial Vaccines; D004337:Drug Carriers; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D011993:Recombinant Fusion Proteins; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; D014763:Viral Matrix Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins