Delayed administration of a bio-engineered zinc-finger VEGF-A gene therapy is neuroprotective and attenuates allodynia following traumatic spinal cord injury.
Following spinal cord injury (SCI) there are drastic changes that occur in the spinal microvasculature, including ischemia, hemorrhage, endothelial cell death and blood-spinal cord barrier disruption. Vascular endothelial growth factor-A (VEGF-A) is a pleiotropic factor recognized for its pro-angiogenic properties; however, VEGF has recently been shown to provide neuroprotection. We hypothesized that delivery of AdV-ZFP-VEGF--an adenovirally delivered bio-engineered zinc-finger transcription factor that promotes endogenous VEGF-A expression--would result in angiogenesis, neuroprotection and functional recovery following SCI. This novel VEGF gene therapy induces the endogenous production of multiple VEGF-A isoforms; a critical factor for proper vascular development and repair. Briefly, female Wistar rats--under cyclosporin immunosuppression--received a 35 g clip-compression injury and were administered AdV-ZFP-VEGF or AdV-eGFP at 24 hours post-SCI. qRT-PCR and Western Blot analysis of VEGF-A mRNA and protein, showed significant increases in VEGF-A expression in AdV-ZFP-VEGF treated animals (p<0.001 and p<0.05, respectively). Analysis of NF200, TUNEL, and RECA-1 indicated that AdV-ZFP-VEGF increased axonal preservation (p<0.05), reduced cell death (p<0.01), and increased blood vessels (p<0.01), respectively. Moreover, AdV-ZFP-VEGF resulted in a 10% increase in blood vessel proliferation (p<0.001). Catwalk™ analysis showed AdV-ZFP-VEGF treatment dramatically improves hindlimb weight support (p<0.05) and increases hindlimb swing speed (p<0.02) when compared to control animals. Finally, AdV-ZFP-VEGF administration provided a significant reduction in allodynia (p<0.01). Overall, the results of this study indicate that AdV-ZFP-VEGF administration can be delivered in a clinically relevant time-window following SCI (24 hours) and provide significant molecular and functional benefits.
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
Sarah A
SA
Figley
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada.
Yang
Y
Liu
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
Spyridon K
SK
Karadimas
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada.
Kajana
K
Satkunendrarajah
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada.
Peter
P
Fettes
Department of Therapeutic Development, Sangamo BioSciences, Pt. Richmond, California, United States of America.
S Kaye
SK
Spratt
Department of Therapeutic Development, Sangamo BioSciences, Pt. Richmond, California, United States of America.
Gary
G
Lee
Department of Therapeutic Development, Sangamo BioSciences, Pt. Richmond, California, United States of America.
Dale
D
Ando
Department of Therapeutic Development, Sangamo BioSciences, Pt. Richmond, California, United States of America.
Richard
R
Surosky
Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
Martin
M
Giedlin
Department of Genetics and Development, Toronto Western Research Institute, and Spinal Program, Krembil Neuroscience Centre, University Health Network, Toronto, Ontario, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada; Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
Michael G
MG
Fehlings
D000256:Adenoviridae; D000818:Animals; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D057809:HEK293 Cells; D006801:Humans; D006930:Hyperalgesia / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D018919:Neovascularization, Physiologic / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D013119:Spinal Cord Injuries / Q000150:complications / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis* / Q000235:genetics; D016335:Zinc Fingers
D042461:Vascular Endothelial Growth Factor A; C467498:vascular endothelial growth factor A, rat