Strategy for the Selection of Scaffolds for Tissue Engineering

Abstract

A strategy for developing scaffolding materials for prostheses capable of inducing tissue regeneration is presented. It is based on knowledge of the stimuli cells need to carry out their programs of division, morphogenesis, and differentiation, that is, of tissue building. The source of the stimulation is shown to be the extracellular matrix (ECM), in or on which cells in tissues live. A capsule view of the molecular diversity and the supramolecular architecture of the ECM is given with the idea that it can be imitated. The desired properties of scaffolding materials assembled from biological and engineering considerations allow the reader to evaluate biomaterials available for creating prostheses. Keeping in mind the ideal properties sought, a series of case histories is presented as a vehicle for examining prosthetic devices, and the materials used for them. Engineered or processed, naturally occurring, tissue replacements for articular cartilage, small caliber artery, periodontal tissues, cruciate ligament, and skin are reviewed from the point of view of how cells react to the scaffolds and how effectively a functional tissue replacement is restored in vivo. An approach to creating scaffolds by deducing their structure mathematically from their function in vivo is discussed as a first step in imitating the design of a body part. Finally touched on is the task of creating information-rich scaffolds like the ECM.

Synthetic Matrices to Serve as Niches for Muscle Cell Transplantation

“…Minimal requirements of the ideal matrix include: (1) biocompatibility (i.e. nonimmunogenic), (2) mechanical properties similar to those of the heart tissue, (3) allowance of biological exchange between the engrafted cells and the host tissue, (4) facilitation of structural and functional integration between newly formed and existing tissue, and (5) gradual degradation (without toxic/immunogenic byproducts) as the implanted cells secrete their own matrix [Bell, 1995].…”

Image-Based Biomimetic Approach to Reconstruction of the Temporomandibular Joint

“…The optimal properties for fabrication of scaffolds from biomaterials have been outlined by Bell [1995]. The ideal scaffold should be biodegradable and nontoxic, have degradation products that are nontoxic, should allow cell attachment, and should be able to be remodeled by the cells.…”

“…It is only through this approach that we will be able to accurately fabricate functional tissue replacement parts [Bell, 1995]. This could be accomplished by making the scaffolds responsive to sitespecific needs of the area to be reconstructed, i.e.…”

“…A scaffold for a TMJ prosthesis should provide interactive and/or functional biologic cues or signals to guide incremental matrix production by either invading or implanted cells [Bell, 1995]. The architectural design of the scaffold/matrix should also be instrumental in influencing biological activity (cell infiltration, attachment, differentiation and function) and mechanical integrity (ability to withstand or distribute mechanical forces) [Ingber, 1993].…”

Fiber Scaffolds of Poly (glycerol-dodecanedioate) and its Derivative via Electrospinning for Neural Tissue Engineering

“…One critical success factor of such an endeavor is to fabricate a skeleton, also known as 'scaffold', to imitate the function of the native extracellular matrix (ECM) [151]. ECM in native tissue interacts constantly with cells through various mechanical and biochemical means [152].…”