title: Tough, Semisynthetic Hydrogels for Adipose Derived Stem Cell Delivery for Chondral Defect Repair.
abstract: Cell-based therapies have great potential to regenerate and repair injured articular cartilage, and a range of synthetic and natural polymer-based hydrogels have been used in combination with stem cells and growth factors for this purpose. Although the hydrogel scaffolds developed to date possess many favorable characteristics, achieving the required mechanical properties has remained a challenge. A hydrogel system with tunable mechanical properties, composed of a mixture of natural and synthetic polymers, and its use for the encapsulation of adipose derived stem/stromal cells (ASCs) is described. Solutions of methacrylated chondroitin sulfate (MCS) are mixed with solutions of acrylate-poly(trimethylene carbonate)-b-poly(ethylene glycol)-b-poly(trimethylene carbonate)-acrylate (PEG-(PTMC-A)2) in phosphate buffered saline and crosslinked via thermally initiated free radical polymerization. The hydrogel compressive equilibrium moduli and toughness are readily tailored by varying the concentration of the pre-polymers, as well as the molecular weight of the PEG used to prepare the PEG-(PTMC-A)2. Two peptide sequences, GVOGEA and GGGGRGDS, are individually conjugated to the MCS to facilitate cell binding. The presence of the peptide ligands yields high ASC viability and long term metabolic activity following encapsulation in hydrogels prepared using the thermal initiator system. Overall, these hydrogels show promise as a minimally invasive ASC delivery strategy for chondral defect repair.
authors.affiliation: Department of Chemical Engineering, Queen's University Kingston, ON, K7L3N6, Canada.|Human Mobility Research Centre, Queen's University Kingston, ON, K7L3N6, Canada.
authors.forename: Fraz
authors.initials: F
authors.lastname: Anjum
authors.affiliation: Department of Chemical Engineering, Queen's University Kingston, ON, K7L3N6, Canada.|Human Mobility Research Centre, Queen's University Kingston, ON, K7L3N6, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Carroll
authors.affiliation: Department of Chemical Engineering, Queen's University Kingston, ON, K7L3N6, Canada.|Human Mobility Research Centre, Queen's University Kingston, ON, K7L3N6, Canada.
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Young
authors.affiliation: Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, ON, N6A 3K7, Canada.|Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON, N6A 3K7, Canada.
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Flynn
authors.affiliation: Department of Chemical Engineering, Queen's University Kingston, ON, K7L3N6, Canada.|Human Mobility Research Centre, Queen's University Kingston, ON, K7L3N6, Canada.
authors.forename: Brian G
authors.initials: BG
authors.lastname: Amsden
mesh_terms: D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D002358:Cartilage, Articular / Q000473:pathology*; D002417:Cattle; D002478:Cells, Cultured; D020100:Hydrogels; D013234:Stem Cells / Q000166:cytology*; D023822:Tissue Engineering
chemical_list: D020100:Hydrogels
keywords: articular cartilage; compressive modulus; hydrogels; stem cells; toughness