title: A rapid-curing alginate gel system: utility in periosteum-derived cartilage tissue engineering.
abstract: In this study, we have developed a rapid-curing alginate gel system and demonstrated its utility as a scaffold for periosteum-derived chondrogenesis for articular cartilage tissue engineering applications. A homogeneous mechanically stable gel was formulated by inducing gelation of a 2% (w/v) solution of a high G content alginate (65-75% G) with a 75 mM solution of CaCl(2). The gel exhibited near-elastic behavior at low levels of deformation (15%, R(2)=0.996), Young's modulus of 0.17+/-0.01 MPa, and rapid gelation kinetics (<1 min to completion). The in vitro cell culture of chondrocytes in the gel yielded alginate/cell constructs that lacked the continuous, interconnected collagen/proteoglycan network of hyaline cartilage. In addition, we have demonstrated that this gel system is capable of supporting periosteum-derived chondrogenesis. We observed that when whole-tissue explants of periosteum were cultured in vitro within the gel, after 6 weeks, significant quantities (>50%) of the total area of the periosteal explants was composed of cartilage that was hyaline-like in appearance and contained cartilage-specific proteoglycans and type-II collagen. It is envisioned that such explants could be transplanted or regenerated in vivo within the biodegradable alginate matrix for the treatment of partial or full-thickness defects in articular cartilage. Importantly, the injectable delivery of the gel could be used in filling complex defects in the articular surface via minimally invasive procedures.
authors: Department of Chemical Engineering, Massachusetts Institute of Technology, 45 Carleton Street, Cambridge, MA 02139, USA.
authors: Molly M
authors: MM
authors: Stevens
authors: Hala F
authors: HF
authors: Qanadilo
authors: Robert
authors: R
authors: Langer
authors: V
authors: V
authors: Prasad Shastri
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002356:Cartilage / Q000166:cytology* / Q000502:physiology; D002358:Cartilage, Articular / Q000166:cytology* / Q000502:physiology; D002417:Cattle; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology; D020219:Chondrogenesis / Q000502:physiology*; D004548:Elasticity; D005109:Extracellular Matrix / Q000502:physiology / Q000648:ultrastructure; D005782:Gels / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry*; D006244:Hardness; D006603:Hexuronic Acids / Q000737:chemistry*; D007700:Kinetics; D008422:Materials Testing / Q000379:methods; D010521:Periosteum / Q000166:cytology* / Q000502:physiology; D044367:Phase Transition; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D005782:Gels; D006603:Hexuronic Acids; D020723:Glucuronic Acid