title: Effect of decellularized adipose tissue particle size and cell density on adipose-derived stem cell proliferation and adipogenic differentiation in composite methacrylated chondroitin sulphate hydrogels.
abstract: An injectable composite scaffold incorporating decellularized adipose tissue (DAT) as a bioactive matrix within a hydrogel phase capable of in situ polymerization would be advantageous for adipose-derived stem cell (ASC) delivery in the filling of small or irregular soft tissue defects. Building on previous work, the current study investigates DAT milling methods and the effects of DAT particle size and cell seeding density on the response of human ASCs encapsulated in photo-cross-linkable methacrylated chondroitin sulphate (MCS)-DAT composite hydrogels. DAT particles were generated by milling lyophilized DAT and the particle size was controlled through the processing conditions with the goal of developing composite scaffolds with a tissue-specific 3D microenvironment tuned to enhance adipogenesis. ASC proliferation and adipogenic differentiation were assessed in vitro in scaffolds incorporating small (average diameter of 38   ±   6 μm) or large (average diameter of 278   ±   3 μm) DAT particles in comparison to MCS controls over a period of up to 21 d. Adipogenic differentiation was enhanced in the composites incorporating the smaller DAT particles and seeded at the higher density of 5   ×   10(5) ASCs/scaffold, as measured by glycerol-3-phosphate dehydrogenase (GPDH) enzyme activity, semi-quantitative analysis of perilipin expression and oil red O staining of intracellular lipid accumulation. Overall, this study demonstrates that decellularized tissue particle size can impact stem cell differentiation through cell-cell and cell-matrix interactions, providing relevant insight towards the rational design of composite biomaterial scaffolds for adipose tissue engineering.
authors.affiliation: Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada.
authors.forename: Cody F C
authors.initials: CF
authors.lastname: Brown
authors.forename: Jing
authors.initials: J
authors.lastname: Yan
authors.forename: Tim Tian Y
authors.initials: TT
authors.lastname: Han
authors.forename: Dale M
authors.initials: DM
authors.lastname: Marecak
authors.forename: Brian G
authors.initials: BG
authors.lastname: Amsden
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Flynn
mesh_terms: D017667:Adipocytes / Q000166:cytology* / Q000637:transplantation*; D050156:Adipogenesis / Q000502:physiology; D000273:Adipose Tissue / Q000737:chemistry* / Q000166:cytology / Q000254:growth & development; D002452:Cell Count; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation / Q000502:physiology; D002474:Cell-Free System; D002478:Cells, Cultured; D002809:Chondroitin Sulfates / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D010316:Particle Size; D033581:Stem Cell Transplantation / Q000295:instrumentation; D013234:Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds
chemical_list: D020100:Hydrogels; D008689:Methacrylates; D002809:Chondroitin Sulfates