RESUMEN
The infectious bronchitis virus (IBV) 4/91 was one of the common IBV variants isolated in Eastern Canada between 2013 and 2017 from chicken flocks showing severe respiratory and production problems. We designed an in vivo experiment, using specific pathogen free (SPF) chickens, to study the pathogenesis of, and host response to, Canadian (CAN) 4/91 IBV infection. At one week of age, the chickens were infected with 4/91 IBV/Ck/Can/17-038913 isolate. Swab samples were collected at predetermined time points. Five birds from the infected and the control groups were euthanized at 3, 7- and 10-days post-infection (dpi) to collect lung and kidney tissues. The results indicate IBV replication in these tissues at all three time points with prominent histological lesions, significant immune cell recruitment and up regulation of proinflammatory mediators. Overall, our findings add to the understanding of the pathogenesis of 4/91 infection and the subsequent host responses in the lungs and kidneys following experimental infection.
Asunto(s)
Infecciones por Coronavirus/inmunología , Interacciones Huésped-Patógeno/inmunología , Virus de la Bronquitis Infecciosa/patogenicidad , Riñón/inmunología , Pulmón/inmunología , Enfermedades de las Aves de Corral/inmunología , Animales , Animales Recién Nacidos , Proteínas Aviares/genética , Proteínas Aviares/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Canadá , Movimiento Celular , Pollos , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , Expresión Génica , Interacciones Huésped-Patógeno/genética , Virus de la Bronquitis Infecciosa/crecimiento & desarrollo , Virus de la Bronquitis Infecciosa/inmunología , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Riñón/virología , Pulmón/virología , Macrófagos/inmunología , Macrófagos/virología , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/inmunología , Enfermedades de las Aves de Corral/patología , Enfermedades de las Aves de Corral/virología , Organismos Libres de Patógenos Específicos , Carga Viral , Replicación ViralRESUMEN
In the early 1930s, infectious bronchitis (IB) was first characterized as a respiratory disease in young chickens; later, the disease was also described in older chickens. The etiology of IB was confirmed later as being due to a coronavirus: the infectious bronchitis virus (IBV). Being a coronavirus, IBV is subject to constant genome change due to mutation and recombination, with the consequence of changing clinical and pathological manifestations. The potential use of live attenuated vaccines for the control of IBV infection was demonstrated in the early 1950s, but vaccine breaks occurred due to the emergence of new IBV serotypes. Over the years, various IBV genotypes associated with reproductive, renal, gastrointestinal, muscular and immunosuppressive manifestations have emerged. IBV causes considerable economic impacts on global poultry production due to its pathogenesis involving multiple body systems and immune suppression; hence, there is a need to better understand the pathogenesis of infection and the immune response in order to help developing better management strategies. The evolution of new strains of IBV during the last nine decades against vaccine-induced immune response and changing clinical and pathological manifestations emphasize the necessity of the rational development of intervention strategies based on a thorough understanding of IBV interaction with the host.
