AAV infection of bovine embryos: Novel, simple and effective tool for genome editing

Adeno-associated viruses (AAV) are widely used in the field of genetically modified organism production. In this work, transduction of bovine embryos by AAV was selected as a potential approach to perform genetic modifications: we have used recombinant AAV to produce GFP-positive bovine embryos. Five different AAV serotypes were used to evaluate their ability to deliver genetic material into the bovine embryos. AAV9 serotype demonstrated minimal effectiveness (38,10%) as the genetic material transfer tool. Four other serotypes of AAVs (AAV1, AAV2, AAV6 and AAV-DJ) showed very close transduction ef-ficiency (52,94-58,33%). CD209 is a C-type lectin receptor which is presented on the surface of mac-rophages and dendritic cells. CD209 recognizes a broad range of pathogens in a rather nonspecific manner. Production of CD209 knock-out is relevant for better understanding of infection mechanisms. Potentially, production of such knock-out may enable animals to become resistant to various infections. We have analyzed DNA samples from 22 blastocysts obtained after in vitro culture of zygotes subjected to recombinant AAV action. We have detected that 3 of 22 analyzed blastocysts contained mosaic CD209 frameshifts. Therefore, we have demonstrated proof of principle that application of AAV as a genome editing tool is an effective method for obtaining genetically modified cattle embryos. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

The study explores the use of recombinant AAV as a transduction tool to achieve genetic modifications in bovine embryos. It demonstrates that AAV1, AAV2, AAV6, and AAV-DJ have high transduction efficiency, highlighting the effectiveness of AAV as a genome editing tool for genetically modified cattle embryos.