Improved viral vector design for homology-independent targeted integration (HITI)

Lead Research Organisation: University of Oxford
Department Name: Medical Sciences DTC

Abstract

Gene therapies for recessive disorders are becoming commonplace, but treatments for dominant gain-of-function disorders are under-researched due to the need to achieve both knock down of the dominant mutant allele and replacement of normal function. This project aims to design high-efficiency AAV vectors with the additional complexity required to tackle dominant disorders. Cas9-mediated Homology-Independent Targeted Integration (HITI) facilitates insertion of an arbitrary sequence at any selected gene editing nuclease cleaved PAM site (Suzuki 2016 PMID:27851729). HITI utilises the NHEJ-pathway, which is substantially more efficient than conventional HDR pathways, and therefore offers more realistic in vivo gene editing strategies. We have a 'HITI reporter' mouse model to allow in vivo HITI to be assessed in any organ. We have preliminary data with AAV Cas9 HITI vectors showing controlled, error-free, PAM-targeted, DNA insertion into mouse liver cells in vivo. As a disease exemplar, we plan to use HITI for the dominant liver disorder, alpha-1 antitrypsin (AAT) deficiency. Specifically, we will target the common, dominant AAT genetic variant (PiZ) that leads to AAT protein precipitation in hepatocytes causing deficient disease-causing levels in the lung. Depending on project progression there is also the opportunity to develop the HITI vector platform for other organs.

Publications

10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
BB/X511341/1 30/09/2022 29/09/2026
2759866 Studentship BB/X511341/1 30/09/2022 29/09/2026 Gavin Turnbull