title: An injectable elastin-based gene delivery platform for dose-dependent modulation of angiogenesis and inflammation for critical limb ischemia.
abstract: Critical limb ischemia is a major clinical problem. Despite rigorous treatment regimes, there has been only modest success in reducing the rate of amputations in affected patients. Reduced level of blood flow and enhanced inflammation are the two major pathophysiological changes that occur in the ischemic tissue. The objective of this study was to develop a controlled dual gene delivery system capable of delivering therapeutic plasmid eNOS and IL-10 in a temporal manner. In order to deliver multiple therapeutic genes, an elastin-like polypeptide (ELP) based injectable system was designed. The injectable system was comprised of hollow spheres and an in situ-forming gel scaffold of elastin-like polypeptide capable of carrying gene complexes, with an extended manner release profile. In addition, the ELP based injectable system was used to deliver human eNOS and IL-10 therapeutic genes in vivo. A subcutaneous dose response study showed enhanced blood vessel density in the treatment groups of eNOS (20 μg) and IL-10 (10 μg)/eNOS (20 μg) and reduced inflammation with IL-10 (10 μg) alone. Next, we carried out a hind-limb ischemia model comparing the efficacy of the following interventions; Saline; IL-10, eNOS and IL-10/eNOS. The selected dose of eNOS, exhibited enhanced angiogenesis. IL-10 treatment groups showed reduction in the level of inflammatory cells. Furthermore, we demonstrated that eNOS up-regulated major proangiogenic growth factors such as vascular endothelial growth factors, platelet derived growth factor B, and fibroblast growth factor 1, which may explain the mechanism of this approach. These factors help in formation of a stable vascular network. Thus, ELP injectable system mediating non-viral delivery of human IL10-eNOS is a promising therapy towards treating limb ischemia.
authors.affiliation: Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA.
authors.forename: Biraja C
authors.initials: BC
authors.lastname: Dash
authors.affiliation: Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland; Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
authors.forename: Dilip
authors.initials: D
authors.lastname: Thomas
authors.affiliation: Department of Cell and Tissue Engineering, Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), 70569 Stuttgart, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Monaghan
authors.affiliation: Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Carroll
authors.affiliation: Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
authors.forename: Xizhe
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, Queen's University, Kingston, ON, Canada.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Woodhouse
authors.affiliation: Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
authors.forename: Timothy
authors.initials: T
authors.lastname: O'Brien
authors.affiliation: Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland. Electronic address: abhay.pandit@nuigalway.ie.
authors.forename: Abhay
authors.initials: A
authors.lastname: Pandit
mesh_terms: D000818:Animals; D002460:Cell Line; D004549:Elastin / Q000737:chemistry*; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D006614:Hindlimb / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D016753:Interleukin-10 / Q000235:genetics; D007511:Ischemia / Q000150:complications / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D008297:Male; D008810:Mice, Inbred C57BL; D018919:Neovascularization, Physiologic; D052250:Nitric Oxide Synthase Type III / Q000235:genetics; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000008:administration & dosage* / Q000235:genetics / Q000627:therapeutic use
chemical_list: C508609:IL10 protein, human; D010455:Peptides; D016753:Interleukin-10; D004549:Elastin; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III
keywords: Angiogenesis; Critical limb ischemia; Elastin-like polypeptide; Gene therapy; Hollow spheres; Inflammation