To eradicate these viruses, Dr. Church and his team engineered a new set of genes and inserted them into pig cells. The genes produced enzymes that hunted for P

To eradicate these viruses, Dr. Church and his team engineered a new set of genes and inserted them into pig cells. The genes produced enzymes that hunted for PERVs and snipped out bits of the viral DNA So the genes were put in some cells that then created the enzymes that actually had the CRISPR/cas9 mechanisms? If so, that's clever. I had imagined that the CRISPR was delivered more directly and I was wondering how you could ensure delivery of CRISPR to all cells in the tissue. With a gene that actually produces an enzyme that delivers CRISPR, the treatment would continue in the cells until the gene was disabled. What would really be interesting is to have the CRISPR edit include the gene that created the enzyme so that it could recursively deliver the treatment. Of course I wouldn't think that we'd want a recursive treatment like that in an eventual solution... but it would be interesting.