title: Cryopreservation of tissue engineered constructs for bone.
abstract: The large-scale clinical use of tissue engineered constructs will require provisions for its mass availability and accessibility. Therefore, it is imperative to understand the effects of low temperature (-196 degrees C) on the tissue engineered biological system. Initial studies used samples of the osteoblast-like cell line (SaOS-2) adhered to a two-dimensional poly(lactide-co-glycolide) thin film (2D-PLAGA) or a three-dimensional poly(lactide-co-glycolide) sintered microsphere matrix (3D-PLAGA) designed for bone tissue engineering. Experimental samples were tested for their ability to maintain cell viability, following low temperature banking for one week, in solutions of the penetrating cryoprotective agents, dimethylsulfoxide (DMSO), ethylene glycol, and glycerol. Results indicated the DMSO solution yielded the greatest percent cell survival for SaOS-2 cells adhered to both the 2D- and 3D-PLAGA scaffolds; therefore, DMSO was used to cryopreserve mineralizing primary rabbit osteoblasts cells adhered to 2D-PLAGA matrices for 35 days. Results indicated retention of the extracellular matrix architecture as no statistically significant difference in the pre- and post-thaw mineralized structures was measured. Percent cell viability of the mineralized constructs following low temperature storage was approximately 50%. These are the first studies to address the issue of preservation techniques for tissue engineered constructs. The ability to successfully cryopreserve mineralized tissue engineered matrices for bone may offer an unlimited and readily available source of bone-like materials for orthopaedic applications.
authors.affiliation: Department of Biomedical Engineering, Drexel University, Philadelphia, PA 19104, USA.
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Kofron
authors.forename: Natalie C
authors.initials: NC
authors.lastname: Opsitnick
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Attawia
authors.forename: Cato T
authors.initials: CT
authors.lastname: Laurencin
mesh_terms: D018786:Bone Substitutes; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D003080:Cold Temperature / Q000009:adverse effects; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D019855:Ethylene Glycol / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology; D006801:Humans; D008863:Microspheres; D010006:Osteoblasts / Q000187:drug effects / Q000648:ultrastructure; D011108:Polymers; D023822:Tissue Engineering
chemical_list: D018786:Bone Substitutes; D003451:Cryoprotective Agents; D011108:Polymers; D019855:Ethylene Glycol; D005990:Glycerol; D004121:Dimethyl Sulfoxide