Your perspective is spot-on IMO. I didn't think you were suggesting that the citation was missing - that's my own curiosity. It seems very odd that the Korn citation appears only at the end of the manuscript. Typically that would be prominently cited when introducing the locus.

Thanks so much for the thoughtful write-up. I only saw Claude's PDF in the last ~12 hours or so, and it closes with a citation of the 2021 Korn paper. Was there an earlier version that lacks any reference to the Korn paper?

Nearly an hour? Tons of time to spare! 😅

Thanks, Martin!

Huge credit to @BrigetteManohar for leading this collaborative effort based at IGI & @berkeleyMCB, which would have been impossible without major contributions from OSU's @TNeuroSci_Lab @RussellLonser and support from NIH's SCGE consortium @somaticediting

Together, these findings establish Neuro-PERC as a versatile, scalable, well-tolerated platform… as well as a promising candidate for clinical translation in neurotherapeutics. 🐭🐷🧠🧬✂️

Finally, we evaluated Neuro-PERC in a severe murine model of Huntington’s disease. Targeting of the human mutant HTT allele produced efficient on-target editing, reduced mutant HTT levels, and extended mouse survival relative to control mice.

Neuro-PERC achieved broad putaminal coverage with clear GFP loss (indicating successful editing) within the successfully targeted area. This confirms that Neuro-PERC can be scaled to large-brained mammals using neurosurgical approaches already in clinical use.

To explore the translational potential of this approach, we performed MRI-guided CED into the putamen (a striatal region) of juvenile pigs at @mizzou. This large-animal model allowed us to evaluate delivery across a brain volume substantially larger than that of the mouse. 🐷🧠

Using a dedicated reporter mouse, adenine base editor (ABE) delivered via Neuro-PERC mediated efficient A→G base editing in vivo, confirming compatibility with multiple CRISPR modalities beyond nuclease-mediated editing.

Neuro-PERC mediated robust in vivo editing of striatal neurons, achieving ~40–60% edited volumes with high reproducibility. Independent validation at @jacksonlab recapitulated results, even after our samples were shipped coast-to-coast.

To determine whether Neuro-PERC supports editing of neurons in vivo, we performed convection-enhanced delivery (CED) into the mouse striatum across multiple reporter models (Ai9, & GFP reporters activated by Cas9 nuclease or adenine base editor).🐭🧠

Neuro-PERC’s particles are ~20 nm, a small size that’s essential for effective spread through brain tissue. This delivery cocktail is compatible with sterile filtration & freeze/thaw. Our brain-ready formulation boosted editing in Ai9-derived NPCs relative to “classic” PERC.

We first evaluated Neuro-PERC in Ai9-derived mouse neural progenitor cells (NPCs). Peptide-enabled delivery markedly increased tdTomato reporter expression relative to Cas9 RNP alone, with peptides A5K & P55 supporting efficient editing without electroporation.

To improve neuronal delivery of CRISPR RNPs, Neuro-PERC combines pre-formed CRISPR enzymes (in RNP format) with endosome-escape peptides, resulting in a simple yet robust cocktail compatible with CNS applications. This builds on PERC, our previous technology.

Big news! Our team developed Neuro-PERC, a non-viral CRISPR delivery platform for genome editing of the brain. In our new preprint - bit.ly/NeuroPERC_pre - we report efficient editing in multiple models & species, including field-first results in large animals (pigs) 🧵👇

Thanks to @GENbio for putting together a nice write-up on this work, which is available here: bit.ly/GEN-hiNLS We put our two favorite hiNLS constructs on @Addgene for anyone interested in giving them a try: addgene.org/search/catalog/p…