Mechanical interlocking of engineered cartilage to an underlying polymeric substrate: towards a biohybrid tissue equivalent.
This study investigates the feasibility of engineering a biohybrid cartilage equivalent (BCE) with the long-term goal of restoring the mechanical integrity and interfacial characteristics of severely damaged cartilage. The BCE depends on the successful adhesion, via mechanical interlocking, of a cartilage layer to a nondegradable composite scaffold or prosthesis. The model scaffold, consisting of a nonwoven mesh bonded to a solid core, was seeded with bovine articular chondrocytes. High molecular weight poly(L-lactic acid), which has a slow degradation time, was used to model the nondegradable polymer. Biochemical and histological analysis demonstrate that the BCE can support the growth of a cartilaginous matrix for at least 6 weeks in culture. Mechanical testing of the BCE showed cartilage adhesion strength increased from 19.27+/-1.62 to 43.79+/-3.88 kPa between 35 and 50 days in culture. Nonmechanically interlocked cartilage achieved less than 5% of this adhesion strength. For the first time, atomic force microscopy (AFM) was used to characterize surface topography of tissue-engineered cartilage. Surface roughness of constructs after 8 and 10 weeks ranged from 153 to 171 nm, falling within the range of native cartilage (100-600 nm). This study demonstrates the feasibility of creating a biohybrid cartilage equivalent by mechanically interlocking a cartilaginous layer to an underlying polymeric matrix.
Biomedical Engineering Department, Northwestern University, Evanston, IL 60208, USA.
Lisa
L
Romito
Guillermo A
GA
Ameer
D000818:Animals; D021522:Bioartificial Organs; D001672:Biocompatible Materials / Q000737:chemistry; D001696:Biomechanical Phenomena / Q000379:methods; D002356:Cartilage / Q000166:cytology* / Q000502:physiology*; D002417:Cattle; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods; D049109:Cell Proliferation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology*; D019544:Equipment Failure Analysis; D019344:Lactic Acid / Q000737:chemistry*; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D011474:Prosthesis Design; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods*
D001672:Biocompatible Materials; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)