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H9N2 viruses have become, over the last 20 years, one of the most diffused poultry pathogens and have reached a level of endemicity in several countries. Attempts to control the spread and reduce the circulation of H9N2 have relied mainly on vaccination in endemic countries. However, the high level of adaptation to poultry, testified by low minimum infectious doses, replication to high titers, and high transmissibility, has severely hampered the results of vaccination campaigns. Commercially available vaccines have demonstrated high efficacy in protecting against clinical disease, but variable results have also been observed in reducing the level of replication and viral shedding in domestic poultry species. Antigenic drift and increased chances of zoonotic infections are the results of incomplete protection offered by the currently available vaccines, of which the vast majority are based on formalin-inactivated whole virus antigens. In our work, we evaluated experimental vaccines based on an H9N2 virus, inactivated by irradiation treatment, in reducing viral shedding upon different challenge doses and compared their efficacy with formalin-inactivated vaccines. Moreover, we evaluated mucosal delivery of inactivated antigens as an alternative route to subcutaneous and intramuscular vaccination. The results showed complete protection and prevention of replication in subcutaneously vaccinated Specific Pathogen Free White Leghorn chickens at low-to-intermediate challenge doses but a limited reduction of shedding at a high challenge dose. Mucosally vaccinated chickens showed a more variable response to experimental infection at all tested challenge doses and the main effect of vaccination attained the reduction of infected birds in the early phase of infection. Concerning mucosal vaccination, the irradiated vaccine was the only one affording complete protection from infection at the lowest challenge dose. Vaccine formulations based on H9N2 inactivated by irradiation demo

Celiac Disease (CD) is an autoimmune enteropathy of the small intestine caused by the consumption of gluten in genetically susceptible individuals, in which participation of the adaptive immune response, and also of the innate immune response is observed.

Introducción: El anticuerpo IgA anti-transglutaminasa tisular 2 (tTG2) es un marcador relevante de la enfermedad celíaca. La utilidad de la determinación de IgA anti-tTG2 está bien establecida para el diagnóstico de la patología, sin embargo su uso para el seguimiento de pacientes con dieta libre de gluten (DLG) no se encuentra del todo esclarecido. Objetivo: Determinar los niveles de IgA anti-tTG2 en pacientes adultos paraguayos con enfermedad celíaca y su relación con la presencia y duración de la DLG. Materiales y métodos: En este estudio observacional descriptivo con componente analítico, transversal, se incluyeron pacientes celíacos adultos, sin (n=23) o con (n=49) DLG. Se determinaron por ELISA los niveles séricos de IgA anti-tTG2. Resultados: Todos (100%) los pacientes celíacos sin DLG presentaron niveles séricos positivos de IgA anti-tTG2. Se observaron niveles séricos de IgA anti-tTG2 significativamente elevados en pacientes celíacos sin DLG en comparación con los niveles en pacientes con DLG. El 35% de los pacientes en tratamiento con DLG (promedio de duración de la dieta = 5,7 años) presentaron niveles positivos (29%) o indeterminados (6%) de IgA anti-tTG2. En relación con la duración de la DLG se observó que al aumentar el tiempo de DLG disminuyen los niveles del auto-anticuerpo (r=-0,2963; p=0,0387). Conclusiones: Los niveles de IgA anti-tTG2 se correlacionaron inversamente con la duración de la DLG. Sin embargo, niveles positivos del anticuerpo persistieron en algunos pacientes, incluso varios años después del inicio de la DLG., Introduction: IgA anti-transglutaminase 2 (tTG2) antibody is a relevant marker in celiac disease. The utility of IgA anti-tTG2 determination is well established for the diagnosis, however their use in the follow-up of patients with gluten free diet (GFD) it is not fully established. Objective: To determine IgA anti-tTG2 antibody levels in adult Paraguayan celiac disease patients and its relation to the presence and duration of the GFD. Materials and methods: Adult celiac disease patients without (n=23) or with (n=49) GFD were included in this observational, descriptive, cross-sectional study with analytical component. IgA anti-tTG2 antibody serum levels were analyzed by ELISA. Results: All (100%) celiac disease patients without GFD had positive anti-tTG2 IgA. Serum levels of IgA anti-tTG2 were significantly elevated in celiac disease patients without GFD compared to levels in patients with GFD. 35% of patients treated with GFD (diet average duration = 5.7 years) had positive (29%) or indeterminate (6%) levels of IgA anti-tTG2. In terms of GFD duration we observed that while the GFD period increased, antibody levels decreased (r=-0.2963; p=0.0387). Conclusion: IgA anti-tTG2 antibody levels correlated inversely with the GFD duration. However, positive levels of these antibodies persisted in some patients, even several years after the onset of GFD.

Informe sobre la estadía realizada en el Laboratorio de Inmunidad Innata, del Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile.