title: Survey of Omp19 immunogenicity against Brucella abortus and Brucella melitensis: influence of nanoparticulation versus traditional immunization.
abstract: Brucellosis is the most common zoonotic bacterial disease. Prevention of human brucellosis is achieved through pasteurization of dairy products, appropriate sanitation and vaccination of domestic animals against the Brucella species. B. abortus unlipidated 19 kDa outer membrane protein (U-Omp19) is a promising candidate for a subunit vaccine against brucellosis. This study investigates immunogenicity of Omp19 alone and with Freund's adjuvant (Omp19-IFA) and N-trimethyl chitosan (TMC/Omp19) nanoparticles, as well as the effect of Omp19 administration route on immunological responses and protection. The omp19 gene was expressed in E. coli BL21 (DE3). After purification, the recombinant Omp19 was loaded onto TMC nanoparticles by ionic gelation with tripolyphosphate. Particle size and loading efficiency of the nanoparticles were determined. Omp19-IFA was administered intraperitoneally while TMC/Omp19 nanoparticles were administered orally and intraperitoneally. The results indicated that intraperitoneal (i.p.) immunization by Omp19-IFA and TMC/Omp19 nanoparticles induced Th1 and Th2 immune responses, respectively, whereas oral immunization of TMC/Omp19 nanoparticles induced a mixed Th1/Th17 immune response. Moreover, oral immunization increased IgA levels in feces. Immunized mice were challenged with virulent B. melitensis 16 M and B. abortus 544. Oral immunization with TMC/Omp19 nanoparticles induced a remarkably high protection level against B. melitensis and B. abortus. The results showed that immunization route has a pivotal role in immune response polarization and protective efficiency of Omp19 antigen. Also, it was deduced that the higher protection level achieved through oral administration of TMC/Omp19 nanoparticles may be due to the elicited Th17 response.
authors.affiliation: Department of Molecular Genetics, Faculty of Basic Sciences, Tarbiat Modarres University, Tehran, Iran.
authors.forename: Morteza
authors.initials: M
authors.lastname: Abkar
authors.affiliation: Department of Clinical Biochemistry, Faculty of Medicine, Tarbiat Modares University, P.O. Box: 14155-6343, Tehran, Iran. lotfi_ab@modares.ac.ir.
authors.forename: Abbas Sahebghadam
authors.initials: AS
authors.lastname: Lotfi
authors.affiliation: Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Vanak Sq. Molasadra St., P.O. Box 19395-5487, Tehran, Iran. Jafar.amani@gmail.com.
authors.forename: Jafar
authors.initials: J
authors.lastname: Amani
authors.affiliation: Nanobiotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Khadijeh
authors.initials: K
authors.lastname: Eskandari
authors.affiliation: Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi Fasihi
authors.initials: MF
authors.lastname: Ramandi
authors.affiliation: Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Vanak Sq. Molasadra St., P.O. Box 19395-5487, Tehran, Iran.|Chemical Injuries Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Jafar
authors.initials: J
authors.lastname: Salimian
authors.affiliation: Department of Microbiology & Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Gholamreza Nikbakht
authors.initials: GN
authors.lastname: Brujeni
authors.affiliation: Brucellosis Department, Razi Vaccine and Serum Research Institute, Karaj, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Alamian
authors.affiliation: Nanobiotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Kamali
authors.affiliation: Nanobiotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Koushki
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D002003:Brucella abortus / Q000276:immunology*; D017347:Brucella melitensis / Q000276:immunology*; D002006:Brucellosis / Q000276:immunology* / Q000517:prevention & control; D016207:Cytokines / Q000032:analysis; D005260:Female; D007114:Immunization / Q000592:standards / Q000662:veterinary*; D007070:Immunoglobulin A / Q000097:blood; D008074:Lipoproteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D053758:Nanoparticles; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D022223:Vaccines, Subunit / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D016207:Cytokines; D007070:Immunoglobulin A; D008074:Lipoproteins; C097319:OMP19 protein, Brucella abortus; D011994:Recombinant Proteins; D022223:Vaccines, Subunit
keywords: Brucellosis; Nanoparticles; Omp19; Oral vaccine; Trimethyl chitosan