In vivobase editing of a pathogenic Eif2b5variant improves vanishing white matter phenotypes in mice

Autor: Böck, Desirée, Revers, Ilma M., Bomhof, Anastasia S.J., Hillen, Anne E.J., Boeijink, Claire, Kissling, Lucas, Egli, Sabina, Moreno-Mateos, Miguel A., van der Knaap, Marjo S., van Til, Niek P., Schwank, Gerald
Zdroj: Molecular Therapy; 20240101, Issue: Preprints
Abstrakt: Vanishing white matter (VWM) is a fatal leukodystrophy caused by recessive mutations in subunits of the eukaryotic translation initiation factor 2B. Currently, there are no effective therapies for VWM. Here, we assessed the potential of adenine base editing to correct human pathogenic VWM variants in mouse models. Using adeno-associated viral vectors, we delivered intein-split adenine base editors into the cerebral ventricles of newborn VWM mice, resulting in 45.9% ± 5.9% correction of the Eif2b5R191Hvariant in the cortex. Treatment slightly increased mature astrocyte populations and partially recovered the integrated stress response (ISR) in female VWM animals. This led to notable improvements in bodyweight and grip strength in females; however, locomotor disabilities were not rescued. Further molecular analyses suggest that more precise editing (i.e., lower rates of bystander editing) as well as more efficient delivery of the base editors to deep brain regions and oligodendrocytes would have been required for a broader phenotypic rescue. Our study emphasizes the potential, but also identifies limitations, of current in vivobase-editing approaches for the treatment of VWM or other leukodystrophies.
Databáze: Supplemental Index