The nature of expression of avian immunity genes during infection with GALLID ALPHAHERPESVIRUS 2 and MELEAGRID ALPHAHERPESVIRUS 1

Abstract

Marek's disease is a dangerous immunosuppressive viral disease of poultry. Most egg poultry farm in the Russian Federation vaccinate their chickens on the first day of life against this viral disease. Thanks to this vaccine prevention tactic, poultry farms protect themselves from the outbreak of this disease and economic damage. Traditionally, among the viruses related to this disease, there are the 1st serotype of the Marek's disease virus (Gallid alphaherpesvirus 2) and the 3rd serotype of the Marek's disease virus, which is not such in a strict taxonomic sense (Meleagrid alphaherpesvirus 1, also called turkey herpesvirus). When poultry is infected, this virus causes a significant change in the expression of the main immunity genes (IL6, PTGS2, IRF7). Based on the results obtained, it was concluded that the expression of the IL6 and PTGS2 genes was slightly higher than the level of expression of these genes in the control group. It is possible that local immunity was suppressed by the immunosuppressive properties of the Marek's disease virus. When studying the expression of the IRF7 gene, a strong effect of viruses of both serotypes on this gene was found, and Gallid alphaherpesvirus 2 exceeded the level of this effect compared to the effect of Meleagrid alphaherpesvirus 1 by 4 times. These results may indicate that sharply increasing expression of the IRF7 gene may be a sign of Marek's disease virus replication (since Gallid alphaherpesvirus 2 and Meleagrid alphaherpesvirus 1 interact with the same cellular receptor, the vaccine effect of Meleagrid alphaherpesvirus 1 is based on this). On the other hand, we can conclude that the introduction of these viruses does not cause inflammatory and immune reactions in the ileocecal tonsils of birds.