title: A novel hydrogel-collagen composite improves functionality of an injectable extracellular matrix.
abstract: Cellular transplantation is now closer to becoming a practical clinical strategy to repair, regenerate or restore the function of skin, muscle, nerves and pancreatic islets. In this study we sought to develop a simple injectable collagen matrix that would preserve the normal cellular organization of skin cells. Three different scaffolds were created and compared: collagen-glycosaminoglycan (GAG) scaffolds, crosslinked collagen-GAG scaffolds without polyvinyl alcohol (PVA) and crosslinked collagen-GAG scaffolds containing PVA hydrogel. Importantly, all scaffolds were found to be non-cytotoxic. PVA-containing gels exhibited a higher tensile strength (P<0.05), faster fibril formation (P<0.001) and reduced collagenase digestion (P<0.01) compared with other gels. Free floating fibroblast-populated, PVA-borate scaffolds resisted contraction over a 10 day period (P<0.001). The fibroblast-populated scaffolds containing PVA demonstrated a 3-fold reduction in cellularity over 10 days compared with the control gels (P<0.001). Multicellular skin substitutes containing PVA-borate networks display a linear cellular organization, reduced cellularity and the formation of a keratinized epidermis that resembles normal skin. In conclusion, these data underscore the multifunctionality of a simple PVA-borate-collagen matrix as an injectable composite for tissue engineering or cell transplantation.
authors.affiliation: Burn and Wound Healing Research Laboratory, Department of Surgery, University of British Columbia, Vancouver, BC, Canada V6H 3Z6.
authors.forename: R
authors.initials: R
authors.lastname: Hartwell
authors.forename: V
authors.initials: V
authors.lastname: Leung
authors.forename: C
authors.initials: C
authors.lastname: Chavez-Munoz
authors.forename: L
authors.initials: L
authors.lastname: Nabai
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: F
authors.initials: F
authors.lastname: Ko
authors.forename: A
authors.initials: A
authors.lastname: Ghahary
mesh_terms: D000818:Animals; D048430:Cell Shape; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry* / Q000648:ultrastructure; D017364:Collagenases / Q000378:metabolism; D005109:Extracellular Matrix / Q000737:chemistry*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D006025:Glycosaminoglycans / Q000737:chemistry; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D007267:Injections; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D008422:Materials Testing; D051381:Rats; D017768:Skin, Artificial; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D006025:Glycosaminoglycans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D003094:Collagen; D017364:Collagenases