RESUMO
There is no vaccine licensed for human use to protect laboratory or field workers against infection with Venezuelan equine encephalitis virus (VEEV). Infection of these groups is most likely to occur via the airborne route and there is evidence to suggest that protection against airborne infection may require high antibody levels and the presence of antibody on the mucosal surface of the respiratory tract. Recombinant defective type 5 adenoviruses, expressing the E3E26K structural genes of VEEV were examined for their ability to protect mice against airborne challenge with virulent virus. After intranasal administration, good protection was achieved against the homologous serogroup 1A/B challenge virus (strain Trinidad donkey). There was less protection against enzootic serogroup II and III viruses, indicating that inclusion of more than one E3E26K sequence in a putative vaccine may be necessary. These studies confirm the potential of recombinant adenoviruses as vaccine vectors for VEEV and will inform the development of a live replicating adenovirus-based VEEV vaccine, deliverable by a mucosal route and suitable for use in humans.
Assuntos
Adenovírus Humanos/genética , Antígenos Virais/genética , Vírus Defeituosos/genética , Vírus da Encefalite Equina Venezuelana/genética , Vírus da Encefalite Equina Venezuelana/imunologia , Proteínas do Envelope Viral/biossíntese , Proteínas do Envelope Viral/genética , Vacinas Virais/genética , Adenovírus Humanos/imunologia , Administração Intranasal , Animais , Antígenos Virais/administração & dosagem , Antígenos Virais/imunologia , Linhagem Celular Tumoral , Vírus Defeituosos/classificação , Vírus da Encefalite Equina Venezuelana/patogenicidade , Encefalomielite Equina Venezuelana/imunologia , Encefalomielite Equina Venezuelana/prevenção & controle , Encefalomielite Equina Venezuelana/virologia , Humanos , Esquemas de Imunização , Camundongos , Camundongos Endogâmicos BALB C , Sorotipagem , Especificidade da Espécie , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Virulência , Replicação Viral/genética , Replicação Viral/imunologiaRESUMO
A mass spectrometry-based method that does not involve the use of radiolabeling was developed for selective detection of phosphopeptides in complex mixtures. Mixtures of phosphorylated and nonphosphorylated peptides at the low picomole level are analyzed by negative ion electrospray liquid chromatography/mass spectrometry using C-18 packed fused-silica columns (≤320-µm i.d.). Peptides and phosphopeptides in the chromatographic eluant undergo collision-induced dissociation in the free-jet expansion region prior to the mass analyzing quadrupole. Using relatively high collisional excitation potentials, phospho|peptides containing phosphoserine, phosphothreonine, and phosphotyrosine fragment to yield diagnostic ions at m/z 63 and 79 corresponding to PO2 (-); and PO3 (-), respectively. Chromatographic peaks containing phosphopeptides are indicated where these diagnostic ions maximize. The highest sensitivity for phosphopeptide detection is obtained using selected-ion monitoring for m/z 63 and 79. Full-scan mass spectra that exhibit the diagnostic phosphopeptide fragment ions, together with pseudomolecular ions, may be obtained by stepping the collisional excitation potential from a high value during the portion of each scan in which the low-mass-to-charge ratio diagnostic marker ions are being detected to a lower value while the upper mass-to-charge ratio range is being scanned. Good sensitivity for phosphopeptide detection was achieved using standard trifluoroacetic acid containing mobile phases for reversed-phase high-performance liquid chromatography. Data illustrating the selectivity and sensitivity of the approach are presented for mixtures of peptides and phosphopeptides containing the three commonly phosphorylated amino acids.
RESUMO
The methods employed in the eradication of various disease carrying mosquitoes and their success rates are discussed. Recommendations are made as to preventative methods which could be employed. (AU)