Stem Cell-Friendly Scaffold Biomaterials: Applications for Bone Tissue Engineering and Regenerative Medicine

Abstract

Bone is a dynamic organ with high regenerative potential and provides essential biological functions in the body, such as providing body mobility and protection of internal organs, regulating hematopoietic cell homeostasis, and serving as important mineral reservoir. Bone defects, which can be caused by trauma, cancer and bone disorders, pose formidable public health burdens. Even though autologous bone grafts, allografts, or xenografts have been used clinically, repairing large bone defects remains as a significant clinical challenge. Bone tissue engineering (BTE) emerged as a promising solution to overcome the limitations of autografts and allografts. Ideal bone tissue engineering is to induce bone regeneration through the synergistic integration of biomaterial scaffolds, bone progenitor cells, and bone-forming factors. Successful stem cell-based BTE requires a combination of abundant mesenchymal progenitors with osteogenic potential, suitable biofactors to drive osteogenic differentiation, and cell-friendly scaffold biomaterials. Thus, the crux of BTE lies within the use of cell-friendly biomaterials as scaffolds to overcome extensive bone defects. In this review, we focus on the biocompatibility and cell-friendly features of commonly used scaffold materials, including inorganic compound-based ceramics, natural polymers, synthetic polymers, decellularized extracellular matrix, and in many cases, composite scaffolds using the above existing biomaterials. It is conceivable that combinations of bioactive materials, progenitor cells, growth factors, functionalization techniques, and biomimetic scaffold designs, along with 3D bioprinting technology, will unleash a new era of complex BTE scaffolds tailored to patient-specific applications.

Applications of 3D Bioprinting in Tissue Engineering and Regenerative Medicine

“…Bone tissue engineering (BTE) is a promising alternative to bone allografts or autografts through the idea of using cell-friendly scaffolds embedded with stem cells and biofactors to fill bony deficits within the body [ 42 ]. For example, one study prepared nano-hydroxyapatite/polyamide scaffolds embedded with mesenchymal stem cells [ 41 ].…”

Stem Cells and Their Derivatives—Implications for Alveolar Bone Regeneration: A Comprehensive Review

“…Moreover, the scaffold must be shapable into different forms with optimal porosity to fill the bone defect. Some materials with the abovementioned properties include the combinations of bioceramics (hydroxyapatite, calcium-phosphates, bioactive glasses, and calcium sulfate), natural polymers (collagen, coralline, chitosan, pectin, silk, hyaluronic acid, and alginate), and synthetic polymers (polylactic acid (PLA), polyglycolic acid (PGA), polylactic-coglycolic acid (PLGA), polyamide polycaprolactone (PCL), and decellularized extracellular matrix (dECM)) [4,85,86]. Equally important is the accurate fabrication of the scaffold, which can now be easily achieved through novel 3D bioprinting technologies.…”

“…There are some other bone tissue substitutes, such as allografts and xenografts; however, their disadvantages include the possibility of immune rejection and pathogen transmission from the donor to the host. The application of synthetic grafts is also limited because of their non-optimal integration with native tissue, which can often lead to graft failure [2][3][4]. As of today, an ideal technique with the ability to completely regenerate harmed bone tissue has not been found.…”

Prospects of Using Biocatalysis for the Synthesis and Modification of Polymers

“…The purpose of this review is to consider the possibilities of using enzymes as catalysts for polymerization, as well as obtaining monomers and oligomers for the synthesis of previously unknown, including biodegradable, polymers. This very dynamically developing field of chemistry is attracting interest due to the need for biodegradable and biocompatible polymeric materials with various functional properties for use in various fields of human activities, including medical applications [ 26 , 27 , 28 , 29 , 30 , 31 ]. Biosynthesis of natural biopolymers—proteins, polysaccharides, DNA and others—is not considered.…”