RESUMO

Se estudiaron 55 bovinos divididos en 3 gruposÑ C, controles no vacunadosñ HS, inmunizados con vacuna hidroxi-saponinada; y EO, inyectados con vacuna oleosa, que se trasladaron y se desafiaron con el virus de la fiebre aftosa (VFA). Se sangraron antes y 7 días después del desafío, y se contaron los leucocitos y subpoblaciones linfocitarias. Todos mostraron marcada neutropenia y eosinofilia, significativamente mayor en el grupo HS que en los grupos C y EO; ambos parámetros mejoraron significativamente en la 2§ sangría. El número total de linfocitos era normal. Las proporción de células B fue normal y no varió en los animales enfermos. Se estudió un grupo de animales antes y despues de la vacunación y viaje: los valores previos fueron normales y significativamente diferentes de los posteriores. Se postula que el stress y la saponina causaron la alteración. Para estudiar la respuesta inmune celular se usó, en los mismos grupos de animales, cultivo de linfocitos periféricos e inhibición de la migración leucocitaria (IML) frente a estimulantes inespecífico (ConA) y específicos (VFA purificado e inactivado de tipos O, A y C). Con ambas técnicas, todos los animales, inclusive los enfermos (C, 2§ sangría) respondieron bien a la ConA y dos animales que enfermaron y curaron respondieron bien al VFA durante 4 meses. Las respuestas al VFA, en C y en vacunados no protegidos, fueron negativas; entre los vacunados protegidos, 2/12 fueron positivos en cultivo y 4/6 en IML. Los resultados indican que...

Assuntos

Bovinos , Animais , Aphthovirus/imunologia , Doenças dos Bovinos/prevenção & controle , Febre Aftosa/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Linfócitos B/análise , Febre Aftosa/sangue , Imunidade Celular , Leucócitos/análise

RESUMO

Se estudiaron 55 bovinos divididos en 3 gruposÑ C, controles no vacunadosñ HS, inmunizados con vacuna hidroxi-saponinada; y EO, inyectados con vacuna oleosa, que se trasladaron y se desafiaron con el virus de la fiebre aftosa (VFA). Se sangraron antes y 7 días después del desafío, y se contaron los leucocitos y subpoblaciones linfocitarias. Todos mostraron marcada neutropenia y eosinofilia, significativamente mayor en el grupo HS que en los grupos C y EO; ambos parámetros mejoraron significativamente en la 2º sangría. El número total de linfocitos era normal. Las proporción de células B fue normal y no varió en los animales enfermos. Se estudió un grupo de animales antes y despues de la vacunación y viaje: los valores previos fueron normales y significativamente diferentes de los posteriores. Se postula que el stress y la saponina causaron la alteración. Para estudiar la respuesta inmune celular se usó, en los mismos grupos de animales, cultivo de linfocitos periféricos e inhibición de la migración leucocitaria (IML) frente a estimulantes inespecífico (ConA) y específicos (VFA purificado e inactivado de tipos O, A y C). Con ambas técnicas, todos los animales, inclusive los enfermos (C, 2º sangría) respondieron bien a la ConA y dos animales que enfermaron y curaron respondieron bien al VFA durante 4 meses. Las respuestas al VFA, en C y en vacunados no protegidos, fueron negativas; entre los vacunados protegidos, 2/12 fueron positivos en cultivo y 4/6 en IML. Los resultados indican que... (AU)

Assuntos

Bovinos , Animais , Aphthovirus/imunologia , Vacinas Virais/imunologia , Febre Aftosa/prevenção & controle , Vacinação/veterinária , Doenças dos Bovinos/prevenção & controle , Imunidade Celular , Leucócitos/análise , Linfócitos B/análise , Febre Aftosa/sangue

RESUMO

Foot and Mouth Disease Virus (FMDV) is one of the most feared animal virus and vaccination still has to be used in many countries. In previous reports, using a murine model, we studied the cellular basis of immune responses against FMDV and were able to show that they are atypical. In cattle, although complete protection may be attained after only one dose of killed virus vaccine, very little is known about protection against FMDV, except for antibody responses, but practically nothing concerning the cellular basis of their immune response. Moreover, since neutralizing titers do not always correlate with protection, the potency of vaccines in controlled by viral challenge. Our aim is to study cellular immune responses against FMDV, and to search for a correlate to protection. As a first step, 55 virgin cattle from a non endemic area (Patagonia) were divided into three groups: C: non immunized controls; HS: immunized with saponine containing vaccine; and EO: with oil emulsified vaccine. After vaccination, they were carried to an endemic area (Buenos Aires), where they were challenged with live FMDV. Animals were bled immediately before and 7 days after challenge, and their white blood cells and lymphocyte subpopulations were counted. All animals showed a marked neutropenia and eosinophilia, significantly higher in HS than in EO and C groups; both parameters were significantly better in the 2nd assay. Total lymphocyte counts were normal. Lymphocyte subpopulations were assessed by immunofluorescence using monoclonal antibodies: their proportions were normal and did not change during illness in group C. Several factors could have induced the observed eosinophilia and neutropenia: parasites, stress, saponine, others.(ABSTRACT TRUNCATED AT 250 WORDS)

Assuntos

Aphthovirus/imunologia , Doenças dos Bovinos/prevenção & controle , Febre Aftosa/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Linfócitos B/química , Bovinos , Doenças dos Bovinos/sangue , Febre Aftosa/sangue , Imunidade Celular , Leucócitos/química

RESUMO

Foot and Mouth Disease Virus (FMDV) is one of the most feared animal virus and vaccination still has to be used in many countries. In previous reports, using a murine model, we studied the cellular basis of immune responses against FMDV and were able to show that they are atypical. In cattle, although complete protection may be attained after only one dose of killed virus vaccine, very little is known about protection against FMDV, except for antibody responses, but practically nothing concerning the cellular basis of their immune response. Moreover, since neutralizing titers do not always correlate with protection, the potency of vaccines in controlled by viral challenge. Our aim is to study cellular immune responses against FMDV, and to search for a correlate to protection. As a first step, 55 virgin cattle from a non endemic area (Patagonia) were divided into three groups: C: non immunized controls; HS: immunized with saponine containing vaccine; and EO: with oil emulsified vaccine. After vaccination, they were carried to an endemic area (Buenos Aires), where they were challenged with live FMDV. Animals were bled immediately before and 7 days after challenge, and their white blood cells and lymphocyte subpopulations were counted. All animals showed a marked neutropenia and eosinophilia, significantly higher in HS than in EO and C groups; both parameters were significantly better in the 2nd assay. Total lymphocyte counts were normal. Lymphocyte subpopulations were assessed by immunofluorescence using monoclonal antibodies: their proportions were normal and did not change during illness in group C. Several factors could have induced the observed eosinophilia and neutropenia: parasites, stress, saponine, others.(ABSTRACT TRUNCATED AT 250 WORDS)