RT Journal Article SR Electronic T1 In vivo high-throughput screening of novel adeno-associated viral capsids targeting adult neural stem cells in the subventricular zone JF bioRxiv FD Cold Spring Harbor Laboratory SP 2021.03.05.434064 DO 10.1101/2021.03.05.434064 A1 Sascha Dehler A1 Lukas PM Kremer A1 Santiago Cerrizuela A1 Thomas Stiehl A1 Jonas Weinmann A1 Heike Abendroth A1 Susanne Kleber A1 Alexander Laure A1 Jihad El Andari A1 Simon Anders A1 Anna Marciniak-Czochra A1 Dirk Grimm A1 Ana Martin-Villalba YR 2021 UL http://biorxiv.org/content/early/2021/03/05/2021.03.05.434064.abstract AB The adult mammalian brain entails a reservoir of neural stem cells (NSCs) generating glial cells and neurons. However, NSCs become increasingly quiescent with age, which hampers their regenerative capacity. New means are therefore required to genetically modify adult NSCs for re-enabling endogenous brain repair. Recombinant adeno-associated viruses (AAVs) are ideal gene therapy vectors due to an excellent safety profile and high transduction efficiency. We thus conducted a high-throughput screening of 177 intraventricularly injected barcoded AAV variants profiled by RNA sequencing. Quantification of barcoded AAV mRNAs identified two synthetic capsids, AAV9_A2 and AAV1_P5, both of which transduce active and quiescent NSCs. Further optimization of AAV1_P5 by judicious selection of promoter and dose of injected viral genomes enabled labeling of 30-60% of the NSC compartment, which was validated by FACS analyses and single cell RNA sequencing. Importantly, transduced NSC readily produced neurons. The present study identifies AAV variants with a high regional tropism towards the v-SVZ with high efficiency in targeting adult NSCs, thereby paving the way for preclinical testing of regenerative gene therapy.Competing Interest StatementD.G. is a co-founder and shareholder of AaviGen GmbH. All other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.