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ARTICLE | Preclinical News

July 31 Preclinical Quick Takes: Sangamo reveals new gene editors; plus a CRISPR prediction model and vaccine boosters for ischemia

July 31, 2019 10:27 PM UTC

Sangamo unveils next-gen ZFN editors
In a Nature Biotechnology study, Sangamo Therapeutics Inc. (NASDAQ:SGMO) reported a next generation zinc finger nuclease (ZFN) gene editing technology with amino acid substitutions in the enzyme’s catalytic domain that improved specificity by slowing down DNA cleavage kinetics, thereby reducing cleavage at low-affinity off-target sites. When combined with additional amino acid substitutions that lowered the affinity of zinc finger domains for genomic sequences, the company showed 98% knockout of the TRAC locus in T cells -- an increasingly popular target in CAR T cell engineering -- with no off-target activity detected by an assay with a detection limit of ~0.01%.

Model predicts CRISPR repair outcomes in T cells
Using data from CRISPR edits at 1,656 genomic sites in primary human T cells, researchers from the Chan Zuckerberg Biohub developed a machine-learning model dubbed SPROUT to predict the length, probability and sequence of nucleotide insertions and deletions induced by CRISPR-Cas9 editing. In a Nature Biotechnology study, the team reported that repair outcomes were similar between donors, but differed across target sites. Authors included co-founders of cell type-specific gene editing company Spotlight Therapeutics Inc. (Hayward, Calif.) and T cell engineering newco Arsenal BioSciences Inc. (South San Francisco, Calif.)...