title: Ex vivo generation of a highly potent population of circulating angiogenic cells using a collagen matrix.
abstract: Biomaterials that have the ability to augment angiogenesis are highly sought-after for applications in regenerative medicine, particularly for revascularization of ischemic and infarcted tissue. We evaluated the culture of human circulating angiogenic cells (CAC) on collagen type I-based matrices, and compared this to traditional selective-adhesion cultures on fibronectin. Culture on a collagen matrix supported the proliferation of CD133(+) and CD34(+)CD133(+) CACs. When subjected to serum starvation, the matrix conferred a resistance to cell death for CD34(+) and CD133(+) progenitors and increased phosphorylation of Akt. After 4days of culture, phenotypically enriched populations of endothelial cells (CD31(+)CD144(+)) and progenitor cells (CD34(+)CD133(+)) emerged. Culture on matrix upregulated the phosphorylation and activation of ERK1/2 pathway members, and matrix-cultured cells also had an enhanced functional capacity for adhesion and invasion. These functional improvements were abrogated when cultured in the presence of ERK inhibitors. The formation of vessel-like structures in an angiogenesis assay was augmented with matrix-cultured cells, which were also more likely to physically associate with such structures compared to CACs taken from culture on fibronectin. In vivo, treatment with matrix-cultured cells increased the size and density of arterioles, and was superior at restoring perfusion in a mouse model of hindlimb ischemia, compared to fibronectin-cultured cell treatment. This work suggests that a collagen-based matrix, as a novel substrate for CAC culture, possesses the ability to enrich endothelial and angiogenic populations and lead to clinically relevant functional enhancements.
authors.affiliation: Division of Cardiac Surgery, University of Ottawa Heart Institute, Ottawa, Ontario, Canada K1Y 4W7. dkura007@uottawa.ca
authors.forename: Drew
authors.initials: D
authors.lastname: Kuraitis
authors.forename: Chenchen
authors.initials: C
authors.lastname: Hou
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Branka
authors.initials: B
authors.lastname: Vulesevic
authors.forename: Tanja
authors.initials: T
authors.lastname: Sofrenovic
authors.forename: Daniel
authors.initials: D
authors.lastname: McKee
authors.forename: Zahra
authors.initials: Z
authors.lastname: Sharif
authors.forename: Marc
authors.initials: M
authors.lastname: Ruel
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Suuronen
mesh_terms: D000818:Animals; D001160:Arterioles / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D001672:Biocompatible Materials / Q000378:metabolism / Q000494:pharmacology; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003094:Collagen / Q000378:metabolism* / Q000494:pharmacology; D016207:Cytokines / Q000097:blood; D005109:Extracellular Matrix / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006614:Hindlimb / Q000098:blood supply; D006801:Humans; D007511:Ischemia / Q000378:metabolism / Q000628:therapy; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D018919:Neovascularization, Physiologic / Q000502:physiology*; D015424:Reperfusion
chemical_list: D001672:Biocompatible Materials; D016207:Cytokines; D003094:Collagen; D048049:Extracellular Signal-Regulated MAP Kinases