RESUMO
The FP9 strain of F has been described as a more immunogenic recombinant vaccine vector than the Webster FPV-M (FPW) strain (R. J. Anderson et al., J. Immunol. 172:3094-3100, 2004). This study expands the comparison to include two separate recombinant antigens and multiple, rather than single, independent viral clones derived from the two strains. Dual-poxvirus heterologous prime-boost vaccination regimens using individual clones of recombinant FP9 or FPW in combination with recombinant modified V Ankara expressing the same antigen were evaluated for their ability to elicit T-cell responses against recombinant antigens from Plasmodium berghei (circumsporozoite protein) or human immunodeficiency virus type 1 (a Gag-Pol-Nef fusion protein). Gamma interferon enzyme-linked immunospot assay and fluorescence-activated cell sorting assays of the responses to specific epitopes confirmed the approximately twofold-greater cellular immunogenicity of FP9 compared to FPW, when given as the priming or boosting immunization. Equality of transgene expression in mouse cells infected with the two strains in vitro was verified by Western blotting. Directed partial sequence analysis and PCR analysis of FPW and comparison to available whole-genome sequences revealed that many loci that are mutated in the highly attenuated and culture-adapted FP9 strain are wild type in FPW, including the seven multikilobase deletions. These "passage-specific" alterations are hypothesized to be involved in determining the immunogenicity of fowlpox virus as a recombinant vaccine vector.
Assuntos
Vírus da Varíola das Aves Domésticas/classificação , Vírus da Varíola das Aves Domésticas/imunologia , Vetores Genéticos/imunologia , HIV-1/genética , Plasmodium berghei/imunologia , Linfócitos T/imunologia , Vacinas de DNA/imunologia , Vacinas contra a AIDS/genética , Vacinas contra a AIDS/imunologia , Animais , Feminino , Vírus da Varíola das Aves Domésticas/genética , Proteínas de Fusão gag-pol/genética , Proteínas de Fusão gag-pol/imunologia , Produtos do Gene nef/genética , Produtos do Gene nef/imunologia , Produtos do Gene nef/metabolismo , HIV-1/imunologia , Humanos , Imunização Secundária , Interferon gama/metabolismo , Vacinas Antimaláricas/genética , Vacinas Antimaláricas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmodium berghei/genética , Poliproteínas/genética , Poliproteínas/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Vacinação , Produtos do Gene nef do Vírus da Imunodeficiência HumanaRESUMO
The possibility that nonculturable cells of a normally culturable bacterial pathogen may constitute a source or reservoir for infective disease was investigated. In multiple experiments and with careful attention to the statistical limitations of the assays used, Salmonella enterica serovar Typhimurium cells rendered nonculturable by carbon and nitrogen stress in the presence of chloramphenicol were administered orally and intraperitoneally to over 300 female BALB/c mice. Neither infection nor colonization was detected in these studies, even when active but nonculturable (ABNC) cells, as defined by the Kogure cell elongation assay, were present in the inoculum. Doses of ABNC cells exceeding the oral and intraperitoneal LD(50) values by 3.5 and 2 orders of magnitude, respectively, were administered. It was concluded that ABNC cells of the salmonella strains used could not be considered potentially infective and that their detection in samples from material being evaluated as a potential source or reservoir of infection by the Kogure test does not specifically represent an infective hazard.
