In vivo genome editing of the albumin locus as a platform for protein replacement therapy
2015; 126 (15): 1777-1784
Site-specific genome editing provides a promising approach for achieving long-term, stable therapeutic gene expression. Genome editing has been successfully applied in a variety of preclinical models, generally focused on targeting the diseased locus itself; however, limited targeting efficiency or insufficient expression from the endogenous promoter may impede the translation of these approaches, particularly if the desired editing event does not confer a selective growth advantage. Here we report a general strategy for liver-directed protein replacement therapies that addresses these issues: zinc finger nuclease (ZFN) -mediated site-specific integration of therapeutic transgenes within the albumin gene. By using adeno-associated viral (AAV) vector delivery in vivo, we achieved long-term expression of human factors VIII and IX (hFVIII and hFIX) in mouse models of hemophilia A and B at therapeutic levels. By using the same targeting reagents in wild-type mice, lysosomal enzymes were expressed that are deficient in Fabry and Gaucher diseases and in Hurler and Hunter syndromes. The establishment of a universal nuclease-based platform for secreted protein production would represent a critical advance in the development of safe, permanent, and functional cures for diverse genetic and nongenetic diseases.
View details for DOI 10.1182/blood-2014-12-615492
View details for Web of Science ID 000365451500011
View details for PubMedID 26297739
View details for PubMedCentralID PMC4600017
Robust ZFN-mediated genome editing in adult hemophilic mice
2013; 122 (19): 3283-3287
Monogenic diseases, including hemophilia, represent ideal targets for genome-editing approaches aimed at correcting a defective gene. Here we report that systemic adeno-associated virus (AAV) vector delivery of zinc finger nucleases (ZFNs) and corrective donor template to the predominantly quiescent livers of adult mice enables production of high levels of human factor IX in a murine model of hemophilia B. Further, we show that off-target cleavage can be substantially reduced while maintaining robust editing by using obligate heterodimeric ZFNs engineered to minimize unwanted cleavage attributable to homodimerization of the ZFNs. These results broaden the therapeutic potential of AAV/ZFN-mediated genome editing in the liver and could expand this strategy to other nonreplicating cell types.
View details for DOI 10.1182/blood-2013-04-497354
View details for Web of Science ID 000327466100013
View details for PubMedID 24085764
View details for PubMedCentralID PMC3821724