The field of regenerative medicine and tissue engineering is an ever evolving field that holds promise in treating numerous
musculoskeletal diseases and injuries. An important impetus in the development of the field was the discovery and implementation of
stem cells. The utilization of mesenchymal stem cells, and later embryonic and induced pluripotent stem cells, opens new arenas for tissue
engineering and presents the potential of developing stem cell-based therapies for disease treatment. Multipotent and pluripotent stem
cells can produce various lineage tissues, and allow for derivation of a tissue that may be comprised of multiple cell types. As the field
grows, the combination of biomaterial scaffolds and bioreactors provides methods to create an environment for stem cells that better represent
their microenvironment for new tissue formation. As technologies for the fabrication of biomaterial scaffolds advance, the ability
of scaffolds to modulate stem cell behavior advances as well. The composition of scaffolds could be of natural or synthetic materials and
could be tailored to enhance cell self-renewal and/or direct cell fates. In addition to biomaterial scaffolds, studies of tissue development
and cellular microenvironments have determined other factors, such as growth factors and oxygen tension, that are crucial to the regulation
of stem cell activity. The overarching goal of stem cell-based tissue engineering research is to precisely control differentiation of
stem cells in culture. In this article, we review current developments in tissue engineering, focusing on several stem cell sources, induction
factors including growth factors, oxygen tension, biomaterials, and mechanical stimulation, and the internal and external regulatory
mechanisms that govern proliferation and differentiation.
Tissue engineering, musculoskeletal tissues, biomaterial scaffolds, stem cell regulation, oxygen, growth factors, extracellular
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