In utero delivery of
densely PEGylated LNPs globally transfects
the brain in utero with mRNA for gene editing enzymes. In this report,
we demonstrate that ADP-LNPs can safely and efficiently transfect
large volumes of the fetal brain tissue with mRNA after an in utero
ICV injection and have the transfection efficiency needed for treating
genetic CNS disorders. We show here that an in utero ICV injection
of
ADP-LNPs can transfect and edit 30% of the entire fetal mouse brain
cells with Cre mRNA, including the proliferating NSPCs, which populate
the entire adult mouse brain as the mouse develops into adulthood.
In addition, in utero ICV injection of ADP-LNPs transfected and edited
15% of the entire fetal mouse brain cells with Cas9 mRNA and efficiently
edited NSPCs. These experiments demonstrate mRNA-based nonviral gene
editing in NSPCs in utero using Cas9 mRNA, achieving high efficiency
and minimal toxicity.