Stem Cells and Nanostructures for Advanced Tissue Regeneration

Abstract

Stem cells are a promising alternative for cell therapy applications because of their self-renewing capability and potential to differentiate into a wide range of specialized cell lineages, including osteoblasts, chondrocytes, cardiomyocytes, and neuronal cells. Different kinds of stem cells are considered for cell-based tissue engineering approaches, of which bone-marrow-derived mesenchymal stem cells (BM-MSCs), adipose-derived stem cells (ADSCs) and embryonic stem cells (ESCs) are frequently utilized for advancement of new tissue engineering strategies. Nanostructures created by natural, synthetic, or composite polymeric biomaterials provide artificial templates of the extracellular matrix (ECM). They possess a high surface area to volume ratio, are porous with good mechanical properties, are sufficient to serve as a biomimetic platform to attract stem cells, cause differentiation, and provide functioning of the tissues. Nanoscale features such as fibers, pits, and grooves modulate cell behavior and might even stimulate the differentiation of stem cells to specific lineages; for example, the nanotopographical cues combined with chemical cues influence the neuronal induction of MSCs, resulting in high microtubule-associated protein expressions. Scaffolds can also be impregnated with several ligands for adhesion of receptors to the cells, or with other regulatory molecules and growth M.P. Prabhakaran (*) and J. Venugopal E3-05-12, Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore e-mail: nnimpp@nus.edu.sg L. Ghasemi-Mobarakeh Islamic Azad University, Najafabad Branch, Isfahan, Iran D. Kai NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore G. Jin and S. Ramakrishna Department of Mechanical Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore factors for designed cell behavior or controlled cell differentiations. Different polymeric blends or fibers incorporated with nanoparticles (such as hydroxyapatite) in aligned or custom-made patterns can induce specific differentiation of stem cells for bone, cartilage, cardiac, nerve, and skin tissue regeneration. In this review, we will discuss the current state of the art and future perspectives on stem cells and their differentiation on nanoengineered substrates for advanced tissue regeneration.

Polycaprolactone nanofibers for the controlled release of tetracycline hydrochloride

“…6]. Tetracycline hydrochloride loaded fibers showed high initial burst release in free form [18]. The release profiles of different concentrations of tetracycline hydrochloride are shown in Fig.…”

In vivointegration of poly(ε-caprolactone)/gelatin nanofibrous nerve guide seeded with teeth derived stem cells for peripheral nerve regeneration

“…Cell transplantation has attracted more interest for treatment of nerve injuries and it has been found to significantly improve the motor and sensory functional recovery of sciatic nerve . Several cell types such as bone marrow mesenchymal stem cells (BMMSCs), mesenchymal stem cells (MSCs), Schwann cells, co‐culture of dorsal root ganglia and Schwann cells and neural stem cells (NSCs) have been used for the improvement of peripheral nerve regeneration through their seeding in conventional nerve guides and the results showed faster improvement of injured nerve and positive impact of these cells on nerve regeneration . However, the use of NSCs from other tissues is considered invasive, and the clinical use of BMMSCs is also limited due to its painful recovery as well as the availability of limited number of harvested cells from BMMSCs …”

Nanofibrous structured biomimetic strategies for skin tissue regeneration

“…Systemic transplantation and local implantation of mesenchymal stem cells (MSCs) are promising treatment methods for skin wounds, especially for chronic wounds . The mechanisms by which BM‐MSCs participate in cutaneous wound healing is by either differentiating into phenotypes of various damaged cells or by enhancing the repair process by creating a microenvironment to promote the local regeneration of endogenous cells to the tissues . MSCs derived from BM are not only capable of supporting hematopoiesis but also differentiating into mesodermal layer cells such as adipocytes, osteoblasts, and chondrocytes.…”