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VEGF Gene Therapy (vegf + gene_therapy)
Selected AbstractsNon-viral VEGF165 gene therapy , magnetofection of acoustically active magnetic lipospheres (,magnetobubbles') increases tissue survival in an oversized skin flap modelJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2010Thomas Holzbach Abstract Adenoviral transduction of the VEGF gene in an oversized skin flap increases flap survival and perfusion. In this study, we investigated the potential of magnetofection of magnetic lipospheres containing VEGF165 -cDNA on survival and perfusion of ischemic skin flaps and evaluated the method with respect to the significance of applied magnetic field and ultrasound. We prepared perfluoropropane-filled magnetic lipospheres (,magnetobubbles') from Tween60-coated magnetic nanoparticles, Metafectene, soybean-oil and cDNA and studied the effect in an oversized random-pattern-flap model in the rats (n= 46). VEGF-cDNA-magnetobubbles were administered under a magnetic field with simultaneously applied ultrasound, under magnetic field alone and with applied ultrasound alone. Therapy was conducted 7 days pre-operative. Flap survival and necrosis were measured 7 days post-operatively. Flap perfusion, VEGF-protein concentration in target and surrounding tissue, formation and appearance of new vessels were analysed additionally. Magnetofection with VEGF-cDNA-magnetobubbles presented an increased flap survival of 50% and increased flap perfusion (P < 0.05). Without ultrasound and without magnetic field, the effect is weakened. VEGF concentration in target tissue was elevated (P < 0.05), while underlying muscle was not affected. Our results demonstrate the successful VEGF gene therapy by means of magnetobubble magnetofection. Here, the method of magnetofection of magnetic lipospheres is equally efficient as adenoviral transduction, but has a presumable superior safety profile. [source] Effect of cell-based VEGF gene therapy on healing of a segmental bone defectJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2009Ru Li Fracture healing requires coordinated coupling between osteogenesis and angiogenesis in which vascular endothelial growth factor (VEGF) plays a key role. We hypothesized that targeted over-expression of angiogenic and osteogenic factors within the fracture would promote bone healing by inducing development of new blood vessels and stimulating/affecting proliferation, survival, and activity of skeletal cells. Using a cell-based method of gene transfer, without viral vector, 5.0,×,106 fibroblasts transfected with VEGF were delivered to a 10-mm bone defect in rabbit tibiae (Group 1) (n,=,9); control groups were treated with fibroblasts (Group 2) (n,=,7), or saline (Group 3) (n,=,7) only. After 12 weeks, eight tibial fractures healed in Group 1, compared to four each in Groups 2 and 3. In Group 1, ossification was seen across the entire defect; in Groups 2 and 3, the defects were fibrous and sparsely ossified. Group 1 had more positively stained (CD31) vessels than Groups 2 and 3. MicroCT 3-D showed complete bridging of the new bone for Group 1, but incomplete healing for Groups 2 and 3. MicroCT bone structural parameters showed significant differences between VEGF treatment and control groups (p,<,0.05). These results indicate that the cell-based VEGF gene therapy has significant angiogenic and osteogenic effects to enhance healing of a segmental defect in the long bone of rabbits. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:8,14, 2009 [source] Tissue Engineering of Urethra Using Human Vascular Endothelial Growth Factor Gene-Modified Bladder Urothelial CellsARTIFICIAL ORGANS, Issue 2 2008Yong Guan Abstract:, Acquired or congenital abnormalities may lead to urethral damage or loss, often requiring surgical reconstruction. Urethrocutaneous fistula and strictures are common complications, due to inadequate blood supply. Thus, adequate blood supply is a key factor for successful urethral tissue reconstruction. In this study, urethral grafts were prepared by seeding rabbit bladder urothelial cells (UCs) modified with human vascular endothelial growth factor (VEGF165) gene in the decellularized artery matrix. A retroviral pMSCV-VEGF165 -GFP vector was cloned by insertion of VEGF open reading frame into the vector pMSCV-GFP (murine stem cell virus [MSCV]; green fluorescent protein [GFP]). Retrovirus was generated using package cell line 293T. Rabbit UCs were expanded ex vivo and modified with either MSCV-VEGF165 -GFP or control MSCV-GFP retrovirus. Transduction efficiency was analyzed by fluorescence-activated cell sorting. The expression of VEGF165 was examined by immunofluorescence, reverse transcript-polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay (ELISA). Decellularized rabbit artery matrix was seeded with genetically modified UCs and was subsequently cultured for 1 week prior to subcutaneous implantation into nude mice. Four weeks after implantation, the implants were harvested and analyzed by fluorescence microscopy, and by histologic and immunohistochemical staining. Ex vivo transduction efficiency of UCs was greater than 50% when concentrated retrovirus was used. The modified cells expressed both VEGF and GFP protein. Furthermore, the VEGF-modified UCs secreted VEGF in a time-dependent manner. Scanning electron microscopy and histochemical analysis of cross sections of the cultured urethral grafts showed that the seeded cells were attached and proliferated on the luminal surface of the decellularized artery matrix. In the subcutaneously implanted vessels, VEGF-modified cells significantly enhanced neovascularization and the formation of a urethral layer compared to GFP-modified cells. These results indicate that VEGF gene therapy may be a suitable approach to increase the blood supply in tissue engineering for treatment of urethral damage or loss. [source] The Society of Academic and Research SurgeryBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue S3 2007Article first published online: 30 JUL 200 The 2007 Annual Meeting of the Society of Academic and Research Surgery was held at Robinson College, Cambridge, UK 10,12th January 2007. The Patey Prize was won by B Modarai et al. (King's College and Imperial College, London, UK) for a paper entitled ,Adenvirus-mediated VEGF gene therapy enhances venous thrombus recanalisation and resolution'. All Patey Prize abstracts are reproduced in the British Journal of Surgery (Br J Surg 2007; 94: 1048,1052). To view all other abstracts from this meeting, please click the pdf link on this page. [source] |