In this project, we will develop a new mouse model for quantitating gene therapy. To promote rigor and
reproducibility, we move away from single gene reporter systems and transition to multiplexed reporter
configurations that are amenable for a broad range of gene editing embodiments. Specifically, we have
designed an expression cassette composed of a monomeric near-infrared fluorescence protein suitable for
deep tissue measurements, a LacZ transgene that provides a rapid visible stain in whole organs and histology
sections, and laboratory evolved red-shifted luciferase that is designed for highly sensitive in vivo
measurements. This flexible configuration will benefit the research community, offering multiple readout
options for investigators.
The described mouse is engineered to detect a broad range of editing embodiments including Cytosine Base
Editors, Adenine Base Editors, Prime-Editors, CasFx, and perhaps others. This ‘all-in-one’ design will allow
researchers to minimize the number of animals needed, thus saving time and cost. It also promotes rigor and
reproducibility since different editing technologies that use the same animal can be more readily quantitatively
compared between research studies performed by different groups, using different delivery agents and
CRISPR embodiments. As of this writing, there are no such mouse models available, hence this project will
provide a novel and unique reagent for the gene therapy field.
We have assembled a strong team to tackle this project, guided by experts in base editors and prime editors
(David Liu and Jennifer Doudna) and mouse genetics (Michael McManus). The project also brings on board a
postdoc co-investigator with expertise in gene therapy in mouse models (Wilson Poon) who has developed a
mouse sensor designed for wtCas9 gene editing. Growing momentum and an ever-increasing body of
evidence indicates that base editors and prime editors will become front-runners in the race to clinical
therapeutics. The development of mouse models will greatly accelerate our goal to bring gene editing to the
clinic, helping to ensure a safer and more efficacious treatment.