title: Formation of an aggregated alginate construct in a tubular perfusion system.
abstract: Tissue engineering strategies are often limited by in vitro culture techniques of three dimensional scaffolds. Here we develop a method to form an aggregated cell-containing construct in vitro in a bioreactor system. Human mesenchymal stem cells (hMSCs) are cultured in individual alginate beads in a tubular perfusion system (TPS) bioreactor and then aggregated to form a single large construct. Mechanical evaluation of this construct demonstrated that aggregated alginate constructs (AACs) made from beads with 2.15 mm diameters had a Young's modulus of 85.6±15.8 kPa, a tensile strength of 3.24±0.55 kPa and a yield strength of 1.44±0.27 kPa. These mechanical properties were shown to be dependent on the bead size used to fabricate the AACs with smaller bead sizes resulting in stronger constructs. Analysis of metabolic activity revealed that hMSCs encapsulated in alginate exposed to AAC treatment sustained metabolic activity while live dead staining indicated cells remain viable. These results demonstrate the formation of AACs in the TPS bioreactor as an elegant method to create tissue engineering constructs in vitro.
authors: Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, USA.
authors: Andrew B
authors: AB
authors: Yeatts
authors: Carly N
authors: CN
authors: Gordon
authors: John P
authors: JP
authors: Fisher
mesh_terms: D000464:Alginates / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D004492:Edetic Acid / Q000494:pharmacology; D020723:Glucuronic Acid / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006603:Hexuronic Acids / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D055595:Mechanical Phenomena / Q000187:drug effects; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008863:Microspheres; D010477:Perfusion / Q000295:instrumentation*; D013194:Staining and Labeling; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D004492:Edetic Acid; D002118:Calcium