Novel mechanically competent polysaccharide scaffolds for bone tissue engineering

Abstract

The success of the scaffold-based bone regeneration approach critically depends on the biomaterial's mechanical and biological properties. Cellulose and its derivatives are inherently associated with exceptional strength and biocompatibility due to their β-glycosidic linkage and extensive hydrogen bonding. This polymer class has a long medical history as a dialysis membrane, wound care system and pharmaceutical excipient. Recently cellulose-based scaffolds have been developed and evaluated for a variety of tissue engineering applications. In general porous polysaccharide scaffolds in spite of many merits lack the necessary mechanical competence needed for load-bearing applications. The present study reports the fabrication and characterization of three-dimensional (3D) porous sintered microsphere scaffolds based on cellulose derivatives using a solvent/non-solvent sintering approach for load-bearing applications. These 3D scaffolds exhibited a compressive modulus and strength in the mid-range of human trabecular bone and underwent degradation resulting in a weight loss of 10-15% after 24 weeks. A typical stress-strain curve for these scaffolds showed an initial elastic region and a less-stiff post-yield region similar to that of native bone. Human osteoblasts cultured on these scaffolds showed progressive growth with time and maintained expression of osteoblast phenotype markers. Further, the elevated expression of alkaline phosphatase and mineralization at early time points as compared to heat-sintered poly(lactic acid-glycolic acid) control scaffolds with identical pore properties affirmed the advantages of polysaccharides and their potential for scaffold-based bone regeneration.

Techniques for the Isolation of High-Quality RNA from Cells Encapsulated in Chitosan Hydrogels

“…Hydrogels derived from chitosan have been extensively studied as biomaterials for tissue engineering applications due to their favorable biocompatibility, biodegradability, and capacity for tailored bioactivity. [1][2][3][4] These materials can be designed as cell delivery vehicles that crosslink in situ to encapsulate cell populations within target sites. In developing these regenerative approaches, gene expression analysis of the encapsulated cell populations by reverse transcriptase-polymerase chain reaction (RT-PCR) can provide useful information in characterizing the cellular response within the engineered microenvironments.…”

Heterogeneity of Scaffold Biomaterials in Tissue Engineering

“…Anisotropic cellulose nanofillers augment mechanical strength of ECM scaffolds allowing for bioengineering of load-bearing tissues, specifically tendons and ligaments [51]. Cellulose also lends itself well to the more rigid tissues of the human body such as bone, cartilage, and cardiac tissues [52,53,54]. …”

Cellulose Nanocrystals as Advanced "Green" Materials for Biological and Biomedical Engineering

“…Recently, bio-nanocomposite scaffolds, using human adult adipose derived mesenchymal stem cells (hASCs), maleic anhydride grafted poly lactic acid and CNCs has been developed for bone tissue engineering applications . In vitro study of cellulose-based porous 3D scaffolds, with mechanical properties in the mid-range of human trabecular bone, promoted positive proliferation and differentiation of human osteoblasts (Kumbar et al, 2011). Hydroxyapatite CNC membranes have also been seen to accelerate new bone formation at the defected sites in rat tibiae, whereas goat bone apatite and CNC composite stimulated bone cell differentiation and proliferation (Tazi et al, 2012;Fan et al, 2013).…”