Advanced Material Strategies for Tissue Engineering Scaffolds

Abstract

Tissue engineering seeks to restore the function of diseased or damaged tissues through the use of cells and biomaterial scaffolds. It is now apparent that the next generation of functional tissue replacements will require advanced material strategies to achieve many of the important requirements for long-term success. Here we provide representative examples of engineered skeletal and myocardial tissue constructs in which scaffolds were explicitly designed to match native tissue mechanical properties as well as to promote cell alignment. We discuss recent progress in microfluidic devices that can potentially serve as tissue engineering scaffolds, since mass transport via microvascular-like structures will be essential in the development of tissue engineered constructs on the length scale of native tissues. Given the rapid evolution of the field of tissue engineering, it is important to consider the use of advanced materials in light of the emerging role of genetics, growth factors, bioreactors, and other technologies.

2010 Nicolas Andry Award: Multipotent Adult Stem Cells from Adipose Tissue for Musculoskeletal Tissue Engineering

“…Immunohistochemical analysis showed significant production of cartilage-associated matrix molecules, including collagen type II and chondroitin-4-sulfate. These findings show that oxygen tension can play an important role in regulating the proliferation and differentiation of human ASCs as they undergo chondrogenesis and suggest that manipulation of the physiochemical culture environment may provide additional means of controlling the activity of undifferentiated progenitor cells in the context of bioreactors [28].…”

Advanced microstructures based on poly(trimethylene carbonate) : microfabrication and stereolithography

“…[81] While engineered tissues thinner than 2 mm can survive by diffusion of oxygen and essential nutrients only (the diffusional penetration of oxygen in native tissues is 100-200 m), this is not sufficient when engineering thicker and more complex tissues like cardiac muscle or liver. [81] For the latter a microvascular system embedded in the scaffold is indispensable to maintain cellular function. [82] Freed et al envisage that a next generation of scaffolds, based on new scaffold materials and structures will be critical for the future success of engineered tissue replacements.…”

“…[81] For clinical applications, the manufacturing process should allow the presence of biological components in certain applications and produce scaffolds in a reproducible, controlled and cost-effective way.…”

Mechanical Reinforcement of Polymeric Fibers through Peptide Nanotube Incorporation

“…Materials whose mechanical and physical properties can be precisely tuned are critical for the fabrication of effective tissue engineering scaffolds, 1 wound dressings, 2,3 medical sutures, filtration devices, and textiles. 4 Increasingly, a composite design in which a high aspect ratio filler material is incorporated within a less-structured matrix is employed in order to match the specific combination of high-performance properties required by the structure.…”

“…While aliphatic polyesters such as PDLLA are convenient to use because they are commercially available and have been deemed safe for human implantation by the FDA, their mechanical and physical properties are suboptimal for applications in which they must replace or augment load-bearing tissues. 18 PDLLA was selected for this study because (1) it is commonly used in the fabrication of implantable biomedical materials, 4 (2) its amorphous structure prevents the creation of nanocrystalline irritants upon biodegradation, 19 yet (3) it is less stiff than its crystalline analogues, and (4) it is unstable when subjected to a static load. 20 Despite the extensive study of self-assembled peptide systems for various applications, there have been few examples 21 of their use as mechanical reinforcement agents.…”