Fabrication of a Bioactive Scaffold Material for Meniscus Tissue Engineering
Scaffold , Biomaterial , Bioactive , Meniscus , Tissue engineering
Injuries to the meniscus are a common and important source of mobility issues in the knees of young active individuals, as well as elderly individuals. Conventional treatments for these injuries involve surgical resections of the damaged portions of tissue in order to relieve immediate clinical symptoms. However, with a decreased amount of meniscal tissue remaining, the load-bearing and load-distribution capacities remain compromised and inevitably lead to the development of osteoarthritis.1 In view of these deficiencies, tissue engineering has emerged as a promising alternative approach to meniscus repair. In this approach, biodegradable synthetic materials have been proposed as scaffolds to stimulate and support cell-mediated tissue remodeling. A wide range of synthetic materials have been developed to respond to the physical and chemical requirements of a scaffold, but many lack the necessary biological properties to respond to cellular stimuli. In addition, many of these materials are deficient in mechanical strength. The aim of this study was to develop a novel biomaterial that addresses these limitations. Poly(trimethylene carbonate) (PTMC) was selected as the main component of the scaffold due its highly suitable material properties. PTMC is a biocompatible, biodegradable polymer with excellent elastomeric properties and mechanical strength. It also offers the advantage of providing long-term mechanical support due to its low degradation rate. However, PTMC alone cannot stimulate tissue regeneration due to its bio-inert nature. In order to provide an ideal environment to support tissue repair, it must possess bioactive signals. PTMC was combined with a collagenase-sensitive peptide substrate to render the scaffold invasive by cells. The peptide also served to increase the slow degradation rate of PTMC by providing cleavage points throughout the network. The compressive strength of this material was significantly higher than previously used scaffold materials. Additionally, the material possessed enhanced toughness and elasticity, high equilibrium water content, and a tunable degradation profile. Unlike currently used scaffolding materials, this material satisfies all of the necessary requirements to function as an effective scaffold for meniscus regeneration.