Construction And Immune Protection Of Recombinats CVI988 Viruses Expressing The Fusion Protein Gene Which Contained MDV GB CTL Epitope Gene And Chicken HSP108 Gene

Marek's disease (MD) is a highly contagious malignant lymphoma of chicken caused by Marek's disease virus (MDV) and has been a major cause of poultry mortality since the 1960s. Fortunately MD could be controlled by use of live attenuated or naturally avirulent vaccines. But the virulence of MDV is increasing, and become more and more virulent. In the early of 1990s, the vv+MDV was isolated, the virus broke through the protection any vaccine virus, such as CVI988, SB-1 or HVT, could supply, so the development of the new-type MD vaccine was impending. In the process of developing the new-type MD vaccine, the attention was focused on the use of CVI988 as a vector. However, a lot of factors influence the development of the new-type vaccine. Among them, the stability and protection of vaccine are main factors. So the researches, including construction and selection of the composed promoter, construction of the fusion protein gene and evaluation of the stability of the recombinant arms, were carried out. Then the recombinant virus containing the composed promoter and fusion protein gene were constructed. At last, the protection of the recombinant viruses were evaluated. These research expected to construct the new-type MD vaccine with the property right reserved, and laid the basis of the new-type vaccine. The study was unfolded through the following aspects: 1. Cloning the glycoprotein B(gB) promoter of Marek's disease virus CVI988 strain and the study of its characteristicTo improve the efficiency of the recombinant Marek's disease viruses(MDV) in chickens with or without maternal antibodies, the appropriate promoter were selected to express the forein gene. The glycoprotein B (gB) promoter of Marek's disease virus (MDV) CVI988 strain was cloned. And he homologue of nucleotide was about 99.5% comparing...