Targeted editing of avian herpesvirus vaccine vector using CRISPR/Cas9 nuclease

Herpesvirus of turkey (HVT) is an avian alphaherpesvirus used as live vaccine against Marek's disease for more than 40 years. HVT is also widely used as a vector platform for generation of recombinant vaccines against other avian diseases using conventional recombination methods or recombineering tools on cloned viral genomes. Here, we describe the application of CRISPR/Cas9-based genome editing as a rapid and efficient method of introducing targeted mutations to the genome of a live herpesvirus vaccine vector using a transfection-infection system. This approach offers a simple and efficient method to manipulate HVT genome for gene function studies and rapid development of recombinant vaccines.