title: A collagen–chitosan hydrogel for endothelial differentiation and angiogenesis.
abstract: Cell therapy for the treatment of cardiovascular disease has been hindered by low cell engraftment, poor survival, and inadequate phenotype and function. In this study, we added chitosan to a previously developed injectable collagen matrix, with the aim of improving its properties for cell therapy and neovascularization. Different ratios of collagen and chitosan were mixed and chemically crosslinked to produce hydrogels. Swell and degradation assays showed that chitosan improved the stability of the collagen hydrogel. In culture, endothelial cells formed significantly more vascular-like structures on collagen–chitosan than collagen-only matrix. While the differentiation of circulating progenitor cells to CD31+ cells was equal on all matrices, vascular endothelial-cadherin expression was increased on the collagen–chitosan matrix, suggesting greater maturation of the endothelial cells. In addition, the collagen–chitosan matrix supported a significantly greater number of CD133+ progenitor cells than the collagen-only matrix. In vivo, subcutaneously implanted collagen–chitosan matrices stimulated greater vascular growth and recruited more von Willebrand factor (vWF+) and CXCR4+ endothelial/angiogenic cells than the collagen-only matrix. These results indicate that the addition of chitosan can improve the physical properties of collagen matrices, and enhance their ability to support endothelial cells and angiogenesis for use in cardiovascular tissue engineering applications.
authors.affiliation: Division of Cardiac Surgery, University of Ottawa Heart Institute, Ottawa, Canada.
authors.forename: Chao
authors.initials: C
authors.lastname: Deng
authors.forename: Pingchuan
authors.initials: P
authors.lastname: Zhang
authors.forename: Branka
authors.initials: B
authors.lastname: Vulesevic
authors.forename: Drew
authors.initials: D
authors.lastname: Kuraitis
authors.forename: Fengfu
authors.initials: F
authors.lastname: Li
authors.forename: Ann Fook
authors.initials: AF
authors.lastname: Yang
authors.forename: May
authors.initials: M
authors.lastname: Griffith
authors.forename: Marc
authors.initials: M
authors.lastname: Ruel
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Suuronen
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D064987:Cell- and Tissue-Based Therapy / Q000379:methods; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry*; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry* / Q000494:pharmacology; D051379:Mice; D018919:Neovascularization, Physiologic / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D003094:Collagen; D048271:Chitosan