Tissue engineering is a promising solution to overcome the limitations of traditional therapeutic strategy. That is the diseased or injured tissues and organs, which are repaired and replaced by using synthetic functional scaffolding material cultured with appropriate cells, harvested from patient or donor, and then re-implanted in the
W. Wang • L. Mei • F. Wang • B. Pei • X. Li (*)
© Springer Nature Singapore Pte Ltd. 2017
X. Li (ed.), Tissue Repair, DOI 10.1007/978-981-10-3554-8_2
Fig. 2.1 Schematic diagram showing key components of scaffold-
based tissue engineering
patient’s body [1, 2]. The core of the method is the manufacture and use of scaffolds to provide a sufficient alternative framework for ex vivo cell expansion and maturation, the growth of natural tissues, and restoration of the original tissue quality according to the tissue’s biochemical composition, morphology and function. In this regard, scaffolds for regenerative medicine play an important role in accommodating and directing cell colonization, migration, growth, and differentiation into specific tissues. The basic idea is to combine the specific cells with a scaffolding material under appropriate conditions for the proper growth of cells and subsequent tissues, as shown in Fig. 2.1. As one more key determinant factor for the success of scaffolds, the interaction of the cell-matrix (scaffold) directs the growth of new tissue . In terms of the biomaterials, the cell-matrix interactions are governed by the surface properties of the implant material, and their imperative interactions have been found within a few nanometer of the surface of the implant . Therefore, the starting material and manufacturing methodology are the most fundamental key points, which determine whether the scaffold is a suitable supporting base for successful cell transplantation therapy.
The native extracellular matrix (ECM) in the body provides a complex and dynamic nano-featured environment of pores, ridges and fibers that exhibit tissue- specific structure and properties for cells growth in the human body [5, 6]. It has been suggested that the characteristics of fibers in the native ECM play an important role in the cell orientation and phenotypic expression. Thus, the scaffold structure that has the ability to facilitate the cell-matrix interactions is critical not only to cell growth behavior but also a key prerequisite for the success of engineering physiologically functional tissues . To achieve this, the use of fibers and tubes as an underlying skeleton or reinforcing agents with or without three-dimensional (3D) matrix provides an effective and workable way to produce composite scaffolds with one or more materials that can better mimic the ECM components and structures. Recent studies have shown that reinforced composite scaffolds not only have 3D porous structures, but also exhibit suitable mechanical properties, high cellularity and better mimicry of the natural tissue organization and composition . Reinforcing scaffolds with fibers or tubes has been suggested to be an effective means of developing engineering materials to provide adequate topographical architecture and mechanical properties for enhancing cells adsorption and selectively altering the tissue orientation of tissue regeneration.
As we all known, it is important not only to select a kind of fiber/tube or the matrix but also to develop a satisfactory processing technique so as to get the homogeneous structure and composition throughout the reinforced scaffolds and obtain good adhesive strength between the matrix and the fibers or tubes [8, 9]. The processing technique should also be able to orient the fibers or tubes in the main trajectories and then lead to an expected final shaping of the reinforced scaffold. Therefore, the manufacturing techniques play a role that can’t be ignored in the development of engineering materials for tissue engineering.
In this chapter, we state the potential matrix and reinforcement materials for the preparation of the scaffolds reinforced by fibers or tubes for tissue repair, as well as their relevant characteristics and properties in conjunction with current research presentations. Furthermore, we also critically review the typical techniques that commonly used to form fiber- or tube- reinforced scaffolds. At the end, concluding remarks and future trends of materials for the fibers or tubes reinforced scaffolds in tissue engineering are included.