Engineered Adipose Tissue from Human Mesenchymal Stem Cells Maintains Predefined Shape and Dimension: Implications in Soft Tissue Augmentation and Reconstruction

Abstract

Soft tissue augmentation is a widespread practice in plastic and reconstructive surgery. The objective of the present study was to engineer adipose tissue constructs with predefined shape and dimensions, potentially utilizable in soft tissue augmentation and reconstruction, by encapsulating adult stem cell-derived adipogenic cells in a biocompatible hydrogel system. Bone marrow-derived adult human mesenchymal stem cells (hMSCs) were preconditioned by 1 week of exposure to adipogenic- inducing supplement followed by photoencapsulation in poly(ethylene glycol) diacrylate (PEGDA) hydrogel in predefined shape and dimensions. In two parallel experiments, the resulting hMSC-derived adipogenic cell-polymer constructs were either incubated in vitro in adipogenic medium or implanted in vivo in the dorsum of immunodeficient mice for 4 weeks. Tissue-engineered adipogenic constructs demonstrated positive reaction to oil red O staining both in vitro and in vivo, and expressed PPAR-gamma2 adipogenic gene marker in vivo. By contrast, control PEGDA hydrogel constructs encapsulating undifferentiated hMSCs failed to demonstrate the adipogenic gene marker and were negative for oil red O staining. Recovered in vitro and in vivo constructs maintained their predefined physical shape and dimensions. These data demonstrate that adipose tissue engineered from human mesenchymal stem cells can retain predefined shape and dimensions for soft tissue augmentation and reconstruction.

Vitronectin-Based, Biomimetic Encapsulating Hydrogel Scaffolds Support Adipogenesis of Adipose Stem Cells

“…Peptides were diluted to 20 mg/mL in PBS and conjugated overnight at 4°C to react the free cysteine on the peptides with the maleimide groups on the linker and create thioester bonds. [12][13][14][15]45 Plates were then blocked for 2 h at room temperature with 1% BSA and washed with PBS to remove excess BSA. ASCs were detached from tissue culture plastic after expansion using TrypLE Select (Life Technologies), diluted for inactivation in serumfree cell culture media, pelleted, resuspended in serum-free media and then stained in suspension with Hoechst 33342 (2 mg/mL; Invitrogen) for 10 min at room temperature for subsequent nuclear visualization.…”

“…[12][13][14][15] The inert backbone of PEG hydrogels, and the relative ease to functionalize sites mimicking extracellular matrix (ECM) proteins to help direct cell fate, make this type of hydrogel appealing for soft tissue reconstruction. [16][17][18] ECM proteins contain sites that cells can bind to and use to interact with their surrounding environment, including neighboring cells.…”

Evolution and Trends in Reconstructive Facial Surgery: An Update

“…Cell homing has been used with significant success in bone engineering, but effort in translating the approach into clinical setting of soft tissue reconstruction or augmentation has made little progress until very recently [1,70]. At this time, it is now possible to restore small facial defects involving bone and soft tissue by cell homing but the restoration of large facial defects may still rely on cell transplantation approach [1].…”

“…Compared with autologous tissue grafts, one of the key advantages of cell-based therapies is to minimize donor site morbidity [1,70]. Unfortunately however, a number of drawbacks have become apparent with early attempts at autologous cell therapies [1].…”

Autologous stem cell regeneration in craniosynostosis

“…Glycosaminoglycan (GAG) content was determined biochemically from lysed chondrogenic cultures using GAG detection kit (Glyscan, Westbury, NY). Adipogenic differentiation was induced by 1 μM dexamethasone, 60 μM indomethacin, 500 μM IBMX (3-Isobutyl-1-methylxanthine), and 10 μg/mL insulin [26]. Lipid formation was determined by Oil-red O staining [26].…”