Bone Differentiation Of Stem Cells Research Articles

Synthesis and Application of Iron Oxide Nanoparticles in Bone Tissue Repair

Nanoparticles play a vital role in bone tissue repair engineering, especially iron oxide nanoparticles (IONPs), which have magnetic properties, semiconductor properties, and nontoxicity at the same time, and their applications in biomedicine have received widespread attention. This review summarizes the excellent performance of IONPs in enhancing scaffold functions, promoting stem cell differentiation, and labeling positioning, in order to understand the research progress and future development trends of IONPs in bone tissue repair engineering, as well as the security issues. Firstly, IONPs can affect the expression of genes and proteins to accelerate the process of biomineralization under a magnetic field. Then, the composite of IONPs and polymers can synthesize a scaffold which can promote the attachment, proliferation, and bone differentiation of stem cells. Furthermore, IONPs can also mark the location of drugs in the body to follow up the process of bone repair. Therefore, extensive research on the manufacturing and application range of IONPs is of great significance to bone tissue repair engineering.

Molecular Control of Interfacial Fibronectin Structure on Graphene Oxide Steers Cell Fate.

The use of graphene-based materials (GBMs) for tissue-engineering applications has been growing exponentially because of the seemingly endless multifunctional and tunable physicochemical properties of graphene that can be exploited to influence cellular behavior. Despite many demonstrations wherein cell physiology has been modulated on different GBMs, a clear mechanism connecting the different physicochemical properties of GBMs to cell fate has remained elusive. In this work, we demonstrate how different GBMs can be used to bias cell fate in a multiscale study-starting from serum protein (fibronectin) adsorption and its molecular scale morphology, structure, and bioactivity and ending with stem cell response. Using heat to chemically reduce graphene oxide without changing physical properties, we show that graphene chemistry controls surface-adsorbed molecular conformation and morphology, epitope presentation, and stem cell attachment. Moreover, this subtle change in the protein structure was found to drive increased bone differentiation of stem cells, suggesting that the physicochemical properties of graphene biases cell fate by directly influencing the adsorbed protein structure and subsequent biochemical activity.

In Vitro Effects of Strontium on Proliferation and Osteoinduction of Human Preadipocytes.

Development of tools to be used for in vivo bone tissue regeneration focuses on cellular models and differentiation processes. In searching for all the optimal sources, adipose tissue-derived mesenchymal stem cells (hADSCs or preadipocytes) are able to differentiate into osteoblasts with analogous characteristics to bone marrow mesenchymal stem cells, producing alkaline phosphatase (ALP), collagen, osteocalcin, and calcified nodules, mainly composed of hydroxyapatite (HA). The possibility to influence bone differentiation of stem cells encompasses local and systemic methods, including the use of drugs administered systemically. Among the latter, strontium ranelate (SR) represents an interesting compound, acting as an uncoupling factor that stimulates bone formation and inhibits bone resorption. The aim of our study was to evaluate the in vitro effects of a wide range of strontium (Sr2+) concentrations on proliferation, ALP activity, and mineralization of a novel finite clonal hADSCs cell line, named PA20-h5. Sr2+ promoted PA20-h5 cell proliferation while inducing the increase of ALP activity and gene expression as well as HA production during in vitro osteoinduction. These findings indicate a role for Sr2+ in supporting bone regeneration during the process of skeletal repair in general, and, more specifically, when cell therapies are applied.

Viral vector-induced expression of bone morphogenetic protein 2 produces inhibition of tumor growth and bone differentiation of stem cells

A number of hormonal factors have been shown to be instrumental in the calcification process. This study represents an attempt at using one of these factors to specifically induce calcification of tumors to arrest tumor growth. The gene encoding bone morphogenetic protein 2 (BMP-2) was placed under transcriptional control of the promoter for carcinoembryonic antigen (CEA). This gene cassette was cloned into a herpes simplex virus (HSV) amplicon vector (HSV-CEA-BMP2). This vector was used to induce local BMP-2 production in CEA-expressing tumor cells to retard cell growth. Lysates of tumor cells treated with HSV-CEA-BMP2 were applied to stem cells to determine if BMP-2 expression promotes differentiation to bone lineage. pHSV-CEA-BMP2 efficiently transduced both CEA-expressing and non-expressing cells. BMP-2 was only expressed in CEA-positive cells. BMP-2 expression led to an inhibition of tumor cell growth. BMP-2 released by these CEA-expressing tumors also drove the differentiation of mesenchymal stem cells to bone lineage. This proof-of-concept study demonstrates that tumor cells can be specifically engineered to produce BMP-2, which leads to growth retardation and to the differentiation of non-committed stem cells to bone. This 'Medusa' effect can theoretically be exploited to retard tumor growth.