MyD88-dependent protective immunity elicited by adenovirus 5 expressing the surface antigen 1 from Toxoplasma gondii is mediated by CD8(+) T lymphocytes

Submitted by Nuzia Santos ([email protected]) on 2014-11-24T17:14:22Z No. of bitstreams: 1 MyD88-dependent protective immunity elicited by adenovirus 5 expressing the surface antigen 1 from Toxoplasma gondii is mediated by CD8(+) T lymphocytes.pdf: 1057989 bytes, checksum: 77f8f8b0d8b766903ef8408045500fd5 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2014-11-24T17:49:07Z (GMT) No. of bitstreams: 1 MyD88-dependent protective immunity elicited by adenovirus 5 expressing the surface antigen 1 from Toxoplasma gondii is mediated by CD8(+) T lymphocytes.pdf: 1057989 bytes, checksum: 77f8f8b0d8b766903ef8408045500fd5 (MD5)Made available in DSpace on 2014-11-24T17:49:07Z (GMT). No. of bitstreams: 1 MyD88-dependent protective immunity elicited by adenovirus 5 expressing the surface antigen 1 from Toxoplasma gondii is mediated by CD8(+) T lymphocytes.pdf: 1057989 bytes, checksum: 77f8f8b0d8b766903ef8408045500fd5 (MD5) Previous issue date: 2011Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Belo Horizonte, MG, BrazilUniversity of Massachusetts Medical School. Division of Infectious Disease and Immunology. Worcester, MA, USAUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Belo Horizonte, MG, Brazil/University of Massachusetts Medical School. Division of Infectious Disease and Immunology. Worcester, MA, USA/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrasilToxoplasma gondii is an intracellular parasite widely spread around the world. The Surface Antigens (SAG) 1, 2 and 3 are the main proteins expressed on the surface of T. gondii tachyzoites. Replication-defective adenovirus serotype 5 (rAd5) is one of the most potent recombinant viral vectors for eliciting T cell-mediated immunity in mice and humans. Here we show that vaccination with rAd5 expressing SAG1 (AdSAG1), but neither SAG2 nor SAG3, induces protective immunity in the highly susceptible C57BL/6 mice challenged with T. gondii. Furthermore, we evaluated different immunological components involved on viral induced protective immunity. We observed that host protection elicited by AdSAG1 is highly dependent on IL-12, IFN-γ and CD8+ T lymphocytes. Importantly, the induction of protective immunity (T cell-derived IFN-γ) was also dependent on Myeloid Differentiation Factor 88 (MyD88), and thus, likely to involve Toll-Like receptors. We conclude that protective parasite specific-CD8+ T cells are elicited by a mechanism that involves MyD88-dependent induction of IL-12

Antibody reactivity against potato apyrase, a protein that shares epitopes with Schistosoma mansoni ATP diphosphohydrolase isoforms, in acute and chronically infected mice, after chemotherapy and reinfection

Submitted by Nuzia Santos ([email protected]) on 2012-11-12T13:56:10Z No. of bitstreams: 1 91.2010.pdf: 765042 bytes, checksum: 027edf486cee8c0006983c9089fee420 (MD5)Made available in DSpace on 2012-11-12T13:56:10Z (GMT). No. of bitstreams: 1 91.2010.pdf: 765042 bytes, checksum: 027edf486cee8c0006983c9089fee420 (MD5) Previous issue date: 2010Fapeapeapemigig, CNPq, CPqRR (to PFP and AAJ), PIBIC, PROBIC/UFJF (to RSS and FHSBUniversidade Federal de Juiz de Fora. Instituto de Ciências Biológicas . Departamento de Bioquímica. Juiz de Fora, MG, Brasil / Santa Casa de Belo Horizonte. Belo Horizonte, MG, Brasil.Universidade Federal de Juiz de Fora. Instituto de Ciências Biológicas. Departamento de Bioquímica. Juiz de Fora, MG, Brasil.Universidade Federal de Juiz de Fora. Instituto de Ciências Biológicas. Departamento de Bioquímica. Juiz de Fora, MG, Brasil.Universidade Federal de Juiz de Fora. Instituto de Ciências Biológicas. Departamento de Bioquímica. Juiz de Fora, MG, Brasil.Universidade Federal de Juiz de Fora. Instituto de Ciências Biológicas. Departamento de Bioquímica. Juiz de Fora, MG, BrasilUniversidade Federal de Juiz de Fora. Instituto de Ciências Biológicas. Departamento de Bioquímica. Juiz de Fora, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Belo Horizonte, MG, Brasil.Santa Casa de Belo Horizonte. Belo Horizonte, MG, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brasil.Universidade Federal de Juiz de Fora. Instituto de Ciências Biológicas . Departamento de Bioquímica. Juiz de Fora, MG, Brasil / Santa Casa de Belo Horizonte. Belo Horizonte, MG, Brasil.Schistosoma mansoni ATP diphosphohydrolase isoforms and potato apyrase share conserved epitopes. By en¬zyme-linked immunosorbent assays, elevated levels of IgM, IgG2a and IgG1 antibody reactivity against potato apy¬rase were observed in S. mansoni-infected BALB/c mice during the acute phase of infection, while only IgM and IgG1 antibody reactivity levels maintained elevated during the chronic phase of infection. Antibody reactivity against po¬tato apyrase was monitored over an 11-month period in chronically-infected mice treated with oxamniquine. Eleven months later, the level of seropositive IgM decreased significantly (~30%) compared to the level found in untreated, infected mice. The level of seropositive IgG1 decreased significantly four months after treatment (MAT) (61%) and remained at this level even after 11 months. The IgG2a reactivity against potato apyrase, although unchanged during chronic phase to 11 MAT, appeared elevated again in re-infected mice suggesting a response similar to that found during the acute phase. BALB/c mouse polyclonal anti-potato apyrase IgG reacted with soluble egg antigens prob¬ably due to the recognition of parasite ATP diphosphohydrolase. This study, for the first time, showed that the IgG2a antibody from S. mansoni-infected BALB mice cross-reacts with potato apyrase and the level of IgG2a in infected mice differentiates disease phases. The results also suggest that different conserved-epitopes contribute to the im¬mune response in schistosomiasis