RESUMEN
Interferons (IFN) provide a critical first line of defense against viral infection in vertebrates. Moreover, IFN-lambda, a recently identified group of mammalian IFN, has demonstrated antiviral potential in the treatment of mammalian viruses. With the growing concern over such diseases as avian influenza (AI), there is a pressing need for new antiviral strategies to manage problem viruses in poultry. Furthermore, the use of immune molecules, such as IFN-lambda, provides an attractive option for treating poultry by augmenting the host response to virus. With this in mind, we report here the first cloning, expression, and analysis of biologic activity of chicken IFN-lambda (ChIFN-lambda). We compared the similarity of ChIFN-lambda to those identified in other species and demonstrate that ChIFN-lambda has antiviral properties similar to those of human IFN-lambda (HuIFN-lambda). Our results demonstrate that in the chicken, as in human, the antiviral activity demonstrated by ChIFN-lambda supports its inclusion in therapeutic strategies directed against viral infections.
Asunto(s)
Interleucinas/genética , Proteínas Recombinantes/genética , Animales , Antivirales/inmunología , Antivirales/farmacología , Línea Celular , Embrión de Pollo , Pollos , Clonación Molecular , Escherichia coli , Humanos , Inmunoterapia Activa , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/inmunología , Gripe Aviar/inmunología , Gripe Aviar/terapia , Interleucinas/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Proteínas Recombinantes/inmunología , Alineación de Secuencia , Receptor Toll-Like 3/biosíntesis , Receptor Toll-Like 3/inmunologíaRESUMEN
DNA vaccination, delivered through various routes, has been used extensively in laboratory animals. Few studies have focused on veterinary species and while results obtained in laboratory animals can often be extrapolated to veterinary species this is not always the case. In this study we have compared the effect of the route of immunisation with DNA on the induction of immune responses and protection of sheep to challenge with live Corynebacterium pseudotuberculosis. Intramuscular injection of plasmid DNA encoding an inactivated form of the phospholipase D (PLD) antigen linked to CTLA4-Ig resulted in the induction of a strong memory response and sterile immunity following challenge in 45% of the animals. In contrast, gene gun delivery or subcutaneous (SC) injection of the DNA vaccine induced comparatively poor responses and insignificant levels of protection. Thus, DNA vaccine efficacy in sheep is strongly influenced by the route of vaccination. Amongst intramuscular vaccinates, protected sheep had significantly elevated IgG2 responses compared to unprotected animals, while both subgroups had equivalent IgG1 levels. This suggests that the presence of IgG2 antibodies and hence a Th1-like response, induced by the DNA vaccine gave rise to protective immunity against C. pseudotuberculosis.