Development of a novel DNA based reverse genetics system for classic human astroviruses

Human astroviruses (HAstVs) are a frequent cause of gastroenteritis in young children and immunocompromised patients. The current report describes a new approach to recover genetically defined HAstVs through the use of a reverse genetics system based on a single DNA plasmid. This plasmid, carrying the full-length virus genome under a T7 promoter, is directly transfected into cells expressing T7 RNA polymerase, resulting in the rapid and robust recovery of infectious HAstV. The efficiency of the system was tested with the generation of a chimeric astrovirus having the HAstV serotype 1 replication machinery and the capsid derived from a HAstV serotype 8 virus. This new system provides an efficient and reproducible method to deepen our knowledge of astrovirus biology.