Strategies to develop endogenous stem cell-recruiting bioactive materials for tissue repair and regeneration

Abstract

A leading strategy in tissue engineering is the design of biomimetic scaffolds that stimulate the body’s repair mechanisms through the recruitment of endogenous stem cells to sites of injury. Approaches that employ the use of chemoattractant gradients to guide tissue regeneration without external cell sources are favored over traditional cell-based therapies that have limited potential for clinical translation. Following this concept, bioactive scaffolds can be engineered to provide a temporally and spatially controlled release of biological cues, with the possibility to mimic the complex signaling patterns of endogenous tissue regeneration. Another effective way to regulate stem cell activity is to leverage the inherent chemotactic properties of extracellular matrix (ECM)-based materials to build versatile cell-instructive platforms. This review introduces the concept of endogenous stem cell recruitment, and provides a comprehensive overview of the strategies available to achieve effective cardiovascular and bone tissue regeneration.

Concise Review: Periodontal Tissue Regeneration Using Stem Cells: Strategies and Translational Considerations

“…The directing of endogenous cells to an injury site in response to biological signals (including but not limited to chemokines, growth factors, cytokines, and cell‐adhesive molecules) is a process known as directed stem cell homing . Clearly, the recruitment of sufficient cell populations to a diseased site is the first step to achieve successful regeneration.…”

Effect of the nano/microscale structure of biomaterial scaffolds on bone regeneration

“…9 However, self-repair is challenging when there are massive bone defects due to traumatic injury, tumor resection, or congenital diseases. 10 Despite the emergence of scaffold-free tissue engineering (TE) as a powerful strategy using cell sheets, spheroids and tissue strands as building blocks, the use of biomaterial scaffolds remains the classical approach to regenerate bone due to the good degradation profile and advantageous mechanical properties, as well as to deliver important biomolecules (such as for the controlled release of growth and differentiation factors) or to immobilize them on the scaffold surface. 10,11 Biomaterials mimicking the configuration of natural ECM can provide a bonelike microenvironment, facilitate stem cell recruitment, and regulate cellular behaviors in terms of cell adhesion, proliferation, migration and differentiation, and leverage the synergistic effect of cytokines for bone regeneration.…”

<p>Growth Factor Gene-Modified Mesenchymal Stem Cells in Tissue Regeneration</p>

“…33 The most commonly studied technique is to add supplemental growth factors that locally provide signals that mimic the process of bone regeneration. 109 It is therefore important to design systems that provide this biological cue in a time-controlled manner so as to mimic the normal bone healing process. Brunger et al attempted to develop a system using poly-L-lysine to immobilize a lentivirus encoding TGF-β3 in a 3D woven poly scaffold to induce robust and sustained cartilaginous extracellular matrix formation by hMSCs.…”

“…125 Therefore, to achieve significant functional benefits, this strategy requires a defined selection of the number and type of stem cells to be delivered, an explicit vector application method, and fixed transduction efficiency and time of administration. In addition, the design of novel bioactive materials such as threedimensional spheroids 126 and nano-active scaffolds 109 to bolster stem cell survival, signaling, and function at the target site can also help to increase the cost-effectiveness of the applications of modified MSCs for tissue repair.…”