Article

An engineered VEGF-activating zinc finger protein transcription factor improves blood flow and limb salvage in advanced-age mice.

Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut, USA.
The FASEB Journal (impact factor: 5.71). 04/2006; 20(3):479-81. DOI:10.1096/fj.04-3670fje pp.479-81
Source: PubMed

ABSTRACT Advances in understanding the relationship between protein structure and DNA binding specificity have made it possible to engineer zinc finger protein (ZFP) transcription factors to specifically activate or repress virtually any gene. To evaluate the potential clinical utility of this approach for peripheral vascular disease, we investigated the ability of an engineered vascular endothelial growth factor (VEGFa)-activating ZFP (MVZ+426b) to induce angiogenesis and rescue hindlimb ischemia in a murine model. Hindlimb ischemia was surgically induced in advanced-age C57/BL6 mice. Adenovirus (Ad) encoding either MVZ+426b or the fluorescent marker dsRed was delivered to the adducter muscle of the ischemic hindlimb, and the effects on blood flow, limb salvage, and vascularization were assessed. Ad-MVZ+426b induced expression of VEGFa at the mRNA and protein levels and stimulated a significant increase in vessel counts in the ischemic limb. This was accompanied by significantly increased blood flow and limb salvage as measured serially for 4 wk. These data demonstrate that activation of the endogenous VEGFa gene by an engineered ZFP can induce angiogenesis in a clinically relevant model and further document the feasibility of designing ZFPs to therapeutically regulate gene expression in vivo.

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Keywords

Ad-MVZ+426b induced expression
 
adducter muscle
 
advanced-age C57/BL6 mice
 
clinically relevant model
 
DNA binding specificity
 
endogenous VEGFa gene
 
engineer zinc finger protein
 
engineered vascular endothelial growth factor
 
engineered ZFP
 
Hindlimb ischemia
 
induce angiogenesis
 
ischemic hindlimb
 
ischemic limb
 
murine model
 
potential clinical utility
 
protein levels
 
protein structure
 
rescue hindlimb ischemia
 
VEGFa)-activating ZFP
 
vessel counts
 

Jun Yu