Lee JS, Grav LM, Pedersen LE, Lee GM, Kildegaard HF. Accelerated homology-directed targeted integration of transgenes in Chinese hamster ovary cells via CRISPR/Cas9 and fluorescent enrichment.
Biotechnol Bioeng 2016;
113:2518-23. [PMID:
27159230 DOI:
10.1002/bit.26002]
[Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 05/02/2016] [Accepted: 05/04/2016] [Indexed: 12/29/2022]
Abstract
Targeted gene integration into site-specific loci can be achieved in Chinese hamster ovary (CHO) cells via CRISPR/Cas9 genome editing technology and the homology-directed repair (HDR) pathway. The low efficiency of HDR often requires antibiotic selection, which limits targeted integration of multiple genes at multiple sites. To improve HDR-mediated targeted integration, while avoiding the use of selection markers, chemical treatment for increased HDR, and fluorescent enrichment of genome-edited cells was assessed in CHO cells. Chemical treatment did not improve HDR-mediated targeted integration. In contrast, fluorescent markers in Cas9 and donor constructs enable FACS enrichment, resulting in a threefold increase in the number of cells with HDR-mediated genome editing. Combined with this enrichment method, large transgenes encoding model proteins (including an antibody) were successfully targeted integrated. This approach provides a simple and fast strategy for targeted generation of stable CHO production cell lines in a rational way. Biotechnol. Bioeng. 2016;113: 2518-2523. © 2016 Wiley Periodicals, Inc.
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