Deletion of the meq gene significantly decreases immunosuppression in chickens caused by pathogenic marek's disease virus

作者：Li, Yanpeng; Sun, Aijun; Su, Shuai; Zhao, Peng; Cui, Zhizhong^*; Zhu, Hongfei

来源：Virology Journal, 2011, 8: 2.

DOI：10.1186/1743-422X-8-2

• RETICULOENDOTHELIOSIS VIRUS
• DNA
• HERPESVIRUS
• TRANSFORMATION
• GENOME
• PP38
• EXPANSION
• STRAINS
• ENCODES
• INVITRO

Background: Marek's disease virus (MDV) causes an acute lymphoproliferative disease in chickens, resulting in immunosuppression, which is considered to be an integral aspect of the pathogenesis of Marek's disease (MD). A recent study showed that deletion of the Meq gene resulted in loss of transformation of T-cells in chickens and a Meq-null virus, rMd5 Delta Meq, could provide protection superior to CVI988/Rispens.
Results: In the present study, to investigate whether the Meq-null virus could be a safe vaccine candidate, we constructed a Meq deletion strain, GX0101 Delta Meq, by deleting both copies of the Meq gene from a pathogenic MDV, GX0101 strain, which was isolated in China. Pathogenesis experiments showed that the GX0101 Delta Meq virus was fully attenuated in specific pathogen-free chickens because none of the infected chickens developed Marek's disease-associated lymphomas. The study also evaluated the effects of GX0101 Delta Meq on the immune system in chickens after infection with GX0101 Delta Meq virus. Immune system variables, including relative lymphoid organ weight, blood lymphocytes and antibody production following vaccination against AIV and NDV were used to assess the immune status of chickens. Experimental infection with GX0101 Delta Meq showed that deletion of the Meq gene significantly decreased immunosuppression in chickens caused by pathogenic MDV.
Conclusion: These findings suggested that the Meq gene played an important role not only in tumor formation but also in inducing immunosuppressive effects in MDV-infected chickens.

• 出版日期2011-1-5
• 单位中国农业科学院; 山东农业大学