RESUMO
The purpose of this study was to monitor local cytokine responses to Dictyocaulus viviparus in calves during primary infection and re-infection. Bronchoalveolar lavage fluid (BALF) was collected weekly from experimentally infected calves and interleukin-2 (IL-2), IL-4, IL-5, IL-10 and IFN-γ mRNA expression was quantified in BALF cells. The major finding was a prominent transient increase in IL-4 mRNA expression, compared with that of uninfected calves, observed in BALF cells collected 2-3 weeks post-primary D. viviparus infection. At 2 weeks post-infection, macroscopic worms were also first observed in BALF. Calves re-infected after 10 weeks were partially immune which was evident at slaughter 5 weeks post-infection as a lower worm burden than in previously naïve calves infected at the same time. IL-4 mRNA expression in BALF cells 2 weeks post-re-infection was increased compared with that of uninfected animals but not as high as that of primarily infected calves. BALF cell expression of the other cytokines tested for was not as clearly effected by the D. viviparus infection. It seems likely that the strong IL-4 response observed during primary infection reflects an innate response to the worms that may initiate an ensuing Th2 response, which confers protective immunity.
Assuntos
Líquido da Lavagem Broncoalveolar/imunologia , Doenças dos Bovinos/imunologia , Infecções por Dictyocaulus/imunologia , Dictyocaulus/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/parasitologia , Complexo CD3/biossíntese , Complexo CD3/genética , Bovinos , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/parasitologia , Citocinas/biossíntese , Citocinas/genética , Dictyocaulus/isolamento & purificação , Dictyocaulus/fisiologia , Infecções por Dictyocaulus/metabolismo , Infecções por Dictyocaulus/parasitologia , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-10/biossíntese , Interleucina-10/genética , Interleucina-2/biossíntese , Interleucina-2/genética , Interleucina-4/biossíntese , Interleucina-4/genética , Interleucina-5/biossíntese , Interleucina-5/genética , Dados de Sequência Molecular , Carga Parasitária , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Recidiva , Fatores de TempoRESUMO
Canine herpesvirus (CHV) is a widespread infection among dogs that typically get latently infected after exposure and can reactivate the infection after stress. The aim of the present study was to study the effects of latent CHV infection during pregnancy on pregnancy outcome, and to study if there are signs of genital viral reactivation during pregnancy or during non-pregnant luteal phase. Twelve mated bitches and eight control bitches were followed and sampled regularly during pregnancy or non-pregnant luteal phase. Blood samples were taken for antibody analysis and vaginal swabs for real-time PCR analysis. Three of the pregnant bitches were vaccinated against CHV during pregnancy. All bitches had antibodies to CHV. Two pregnant bitches that were not vaccinated had a twofold or larger increase in CHV titre, with no negative effects detected on pregnancy. Higher titres were not associated with smaller litters or with vaccination. There was no consistent variation in antibody titres due to pregnancy or non-pregnant luteal phase. Vaginal excretion of CHV was not detected from any of the bitches.
