ABSTRACT
Live attenuated C-strain classical swine fever vaccines provide early onset protection. These vaccines confer effective protection against the disease at 5-7 days post-vaccination. It was previously reported that intramuscular administration of the Porvac® vaccine protects against highly virulent classical swine fever virus (CSFV) "Margarita" strain as early as seven days post-vaccination. In order to identify how rapidly protection against CSFV is conferred after a single dose of the Porvac® subunit vaccine E2-CD154, 15 swine, vaccinated with a single dose of Porvac®, were challenged intranasally at five, three, and one day post-vaccination with 2 × 103 LD50 of the highly pathogenic Cuban "Margarita" strain of the classical swine fever virus. Another five animals were the negative control of the experiment. The results provided clinical and virological data confirming protection at five days post-vaccination. Classical swine fever (CSF)-specific IFNγ T cell responses were detected in vaccinated animals but not detected in unvaccinated control animals. These results provided the first data that a subunit protein vaccine demonstrates clinical and viral protection at five days post-vaccination, as modified live vaccines.
ABSTRACT
The use of DNA vectors based on the SFV (Semliki Forest virus) replicon have not been reported in the modality of DNA prime virus boost. In the present study, SFV DNA vectors (DNA vectors based on the SFV replicon) bearing the HIV-1 TAB9 multiepitopic polypeptide minigene were evaluated as priming DNA immunogens followed by a recombinant fowlpox expressing the TAB9 mutiepitope (FPTAB9LZ) boost. The results indicated that mice primed with pSFV(k)tab9 and boosted with FPTAB9LZ significantly decreased the HIV-1 recombinant (VVTAB13, a recombinant vaccinia virus expressing the TAB13 multiepitope) vaccinia virus replication, compared with groups given pSFV(k)tab9 vector and FPTAB9LZ virus alone. Additionally, the viral titre in ovary correlated with the number of specific gamma-interferon-secreting T-cells in spleen. These results support the possible use of SFV DNA vectors in prime-boost approaches implemented in therapeutic/prophylactic treatments for infectious diseases such as HIV-1.
Subject(s)
DNA, Viral/administration & dosage , Fowlpox virus/genetics , Genetic Therapy/methods , HIV Infections/prevention & control , Immunization, Secondary/methods , Semliki forest virus/genetics , Vaccines, DNA/administration & dosage , Animals , Combined Modality Therapy , Female , Fowlpox virus/immunology , HIV Infections/genetics , HIV Infections/immunology , Mice , Mice, Inbred BALB C , Semliki forest virus/immunology , Treatment Outcome , Vaccination/methods , Vaccines, DNA/immunologyABSTRACT
La esperanza de cortar el paso devastador de la pandemia de vih/sida descansa, en buena medida, en la obtención de una vacuna eficaz contra este mal. A veinte años del descubrimiento del vih, el optimismo inicial mostró que era infundado: además de que no se ha logardo una vacuna efectiva, las perspectivas para su obtención a corto plazo son aún inciertas. Dentro del artículo se plantean distintos aspectos tales como características distintivas del vih, indicadores de protección contra el vih/sida, candidatos vacunales evaluados en ensayos clínicos, expectativas de la aplicación de una vacuna preventiva contra el vih/sida(AU)
Subject(s)
HumansABSTRACT
A preformulation study was performed for the evaluation of a vaccine candidate against HIV-1. Aluminium hydroxide was used in the preformulation. However, this adjuvant is not a good adsorbent for basic proteins since it is positively charged at a physiological pH. In the present study, we determined the adsorption of TAB9 (basic protein, pI: 11.3) by treating Alhydrogel with different ions. The immunogenicity of the vaccine candidate against HIV was also evaluated using three batches, 9801-A, 9802-A and 9803-A, and a placebo P-001. The evaluation was performed twice (0 and 9 months). Each batch was tested using groups of 10 mice that had a single inoculation. The results showed that the protein was totally adsorbed to the aluminium gel. Seroconvertion was attained in all analysed batches, indicating the potentiality of TAB9 as a vaccine candidate.
Subject(s)
AIDS Vaccines/immunology , Aluminum Hydroxide/chemistry , Epitopes/chemistry , Epitopes/immunology , HIV-1/immunology , Vaccines, Synthetic/immunology , Adjuvants, Immunologic/chemistry , Adsorption , Animals , Female , HIV Antigens/immunology , HIV Seropositivity/immunology , Humans , Mice , Mice, Inbred BALB C , Phosphates/chemistry , Reference Values , Sensitivity and SpecificityABSTRACT
Se estudió y comparó la presencia de anticuerpos neutralizantes (AcN) frente a 5 cepas de laboratorio del virus de la inmunodeficiencia humana tipo 1 (VIH-1) en el suero de 8 macacos (Macaca fascicularis) después de la tercera y cuarta inmunización con el polipéptido multiepitópico TAB9, emulsificado con el adyuvante Montanide ISA 720; 4 animales se inocularon con 1 mg y los otros con 200 µg, como control se inyectaron 2 animales sólo con el adyuvante. Aunque se comprobó la presencia de anticuerpos neutratizantes en la mayoría de los animales, después de las inmunizaciones frente a cepas homólogas del grupo B del VIH-1 por el método ELISA de captura de antígeno p24 (DAVIH-Ag p24, Cuba), no se detectaron diferencias estadísticamente significativas en los títulos provocados por las concentraciones de antígeno ni en las respuestas después de la tercera y cuarta dosis inmunizante. Los animales controles no desarrollaron anticuerpos neutralizantes(AU)