title: Toxoplasma gondii: humoral and cellular immune response of BALB/c mice immunized via intranasal route with rTgROP2.
abstract: TgROP2 is an intracellular protein associated with rhoptries of Toxoplama gondii and an antigen component of a candidate vaccine for toxoplasmosis. The purpose of the present study was to evaluate the efficacy of rTgROP2 to stimulate humoral and cellular immune responses in BALB/c mice via intranasal injection. TgROP2 partial coding sequence was (196-561) amplified by PCR from genomic T. gondii RH strain DNA and cloned into the pTrcHis expression vector. Escherichia coli Rosetta 2 cells transformed with pTrcHis-TgROP2 showed high levels (~1 mg.mL(-1)) of recombinant protein after 4 hours of IPTG induction. Recombinant TgROP2 exhibited an apparent Mr equal to 54 kDa. In order to test immunogenicity of the recombinant protein, 10 BALB/c mice received 10 µg of rROP2 protein + 10 µg of Quil-A via intranasal injection. Doses were administered at days 0, 21, and 42. Three animals were euthanized and used to evaluate cellular immune response on day 62. Five (50%) and two (20%) out of ten animals produced IgG (DO mean = 0.307; cut-off = 0.240) and IgA (DO mean = 0.133, cut-off = 0.101), respectively, by ELISA on day 62. The proliferation of splenocytes revealed high stimulation index (SI) when co-cultured with 5, 10 and 15 µg.mL(-1) of rTgROP2. These results indicate that intranasal immunization with recombinant protein ROP2 plus Quil-A can elicit both cellular and humoral immune responses in BALB/c mice.
authors.affiliation: Laboratório de Protozoologia, Departamento de Medicina Veterinária Preventiva, Universidade de Londrina, Londrina-PR, Brazil.
authors.forename: Michelle
authors.initials: M
authors.lastname: Igarashi
authors.forename: Dauton Luiz
authors.initials: DL
authors.lastname: Zulpo
authors.forename: Ivo Alexandre Leme da
authors.initials: IA
authors.lastname: Cunha
authors.forename: Luiz Daniel
authors.initials: LD
authors.lastname: Barros
authors.forename: Vanessa Figueredo
authors.initials: VF
authors.lastname: Pereira
authors.forename: Alessandra
authors.initials: A
authors.lastname: Taroda
authors.forename: Italmar Teodorico
authors.initials: IT
authors.lastname: Navarro
authors.forename: Odilon
authors.initials: O
authors.lastname: Vidotto
authors.forename: Marilda Carlos
authors.initials: MC
authors.lastname: Vidotto
authors.forename: Mark Christopher
authors.initials: MC
authors.lastname: Jenkins
authors.forename: João Luis
authors.initials: JL
authors.lastname: Garcia
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology*; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology; D015800:Protozoan Proteins / Q000276:immunology*; D016052:Protozoan Vaccines / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D008565:Membrane Proteins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; C090555:ROP 2 protein, Toxoplasma gondii