title: In Vivo Assessment of Bone Regeneration in Alginate/Bone ECM Hydrogels with Incorporated Skeletal Stem Cells and Single Growth Factors.
abstract: The current study has investigated the use of decellularised, demineralised bone extracellular matrix (ECM) hydrogel constructs for in vivo tissue mineralisation and bone formation. Stro-1-enriched human bone marrow stromal cells were incorporated together with select growth factors including VEGF, TGF-β3, BMP-2, PTHrP and VitD3, to augment bone formation, and mixed with alginate for structural support. Growth factors were delivered through fast (non-osteogenic factors) and slow (osteogenic factors) release PLGA microparticles. Constructs of 5 mm length were implanted in vivo for 28 days within mice. Dense tissue assessed by micro-CT correlated with histologically assessed mineralised bone formation in all constructs. Exogenous growth factor addition did not enhance bone formation further compared to alginate/bone ECM (ALG/ECM) hydrogels alone. UV irradiation reduced bone formation through degradation of intrinsic growth factors within the bone ECM component and possibly also ECM cross-linking. BMP-2 and VitD3 rescued osteogenic induction. ALG/ECM hydrogels appeared highly osteoinductive and delivery of angiogenic or chondrogenic growth factors led to altered bone formation. All constructs demonstrated extensive host tissue invasion and vascularisation aiding integration and implant longevity. The proposed hydrogel system functioned without the need for growth factor incorporation or an exogenous inducible cell source. Optimal growth factor concentrations and spatiotemporal release profiles require further assessment, as the bone ECM component may suffer batch variability between donor materials. In summary, ALG/ECM hydrogels provide a versatile biomaterial scaffold for utilisation within regenerative medicine which may be tailored, ultimately, to form the tissue of choice through incorporation of select growth factors.
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Gothard
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Emma L
authors.initials: EL
authors.lastname: Smith
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Janos M
authors.initials: JM
authors.lastname: Kanczler
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Black
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Julia A
authors.initials: JA
authors.lastname: Wells
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Carol A
authors.initials: CA
authors.lastname: Roberts
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: White
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.
authors.forename: Omar
authors.initials: O
authors.lastname: Qutachi
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.
authors.forename: Heather
authors.initials: H
authors.lastname: Peto
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.
authors.forename: Hassan
authors.initials: H
authors.lastname: Rashidi
authors.affiliation: Department of Materials, Imperial College London, Royal School of Mines, London, SW7 2AZ, United Kingdom.|Department of Bioengineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom.|Institute for Biomedical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom.|Biomaterials, Biomimetics, Biophotonics Research Division, King's College London, Dental Institute, Guy's Hospital, Tower Wing, London Bridge, London SE1 9RT, United Kingdom.
authors.forename: Luis
authors.initials: L
authors.lastname: Rojo
authors.affiliation: Department of Materials, Imperial College London, Royal School of Mines, London, SW7 2AZ, United Kingdom.|Department of Bioengineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom.|Institute for Biomedical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom.
authors.forename: Molly M
authors.initials: MM
authors.lastname: Stevens
authors.affiliation: Institute for Science and Technology in Medicine, Keele University, Guy Hilton Research Centre, Stoke-on-Trent, ST4 7BQ, United Kingdom.
authors.forename: Alicia J
authors.initials: AJ
authors.lastname: El Haj
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.
authors.forename: Felicity R A J
authors.initials: FR
authors.lastname: Rose
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, School of Pharmacy, University of Nottingham, Centre for Biomolecular Sciences, University Park, Nottingham, NG7 2RD, United Kingdom.|Locate Therapeutics Limited, MediCity, Nottingham, NG90 6BH, United Kingdom.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Shakesheff
authors.affiliation: Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton, SO16 6YD, United Kingdom.
authors.forename: Richard O C
authors.initials: RO
authors.lastname: Oreffo
mesh_terms: D000464:Alginates / Q000009:adverse effects / Q000737:chemistry; D000818:Animals; D001861:Bone Regeneration; D020219:Chondrogenesis; D005109:Extracellular Matrix; D020723:Glucuronic Acid / Q000009:adverse effects / Q000737:chemistry; D006603:Hexuronic Acids / Q000009:adverse effects / Q000737:chemistry; D006801:Humans; D020100:Hydrogels / Q000009:adverse effects / Q000737:chemistry*; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology*; D019344:Lactic Acid / Q000009:adverse effects / Q000737:chemistry; D051379:Mice; D008875:Middle Aged; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism / Q000637:transplantation; D010012:Osteogenesis; D011100:Polyglycolic Acid / Q000009:adverse effects / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D054457:Tissue Scaffolds / Q000009:adverse effects / Q000737:chemistry
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020100:Hydrogels; D036341:Intercellular Signaling Peptides and Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D020723:Glucuronic Acid