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While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe2O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through a hydrothermal process. After that, the piezoelectric PVDF polymer, which contained the magnetic nanoparticles, underwent the electrospun process to form ME nanofibers, the ME property of which has the potential to be used in areas such as tissue engineering, biosensors, and actuators.

In recent years, induced pluripotent stem cells (iPSCs) have been considered as a promising approach in the field of regenerative medicine. iPSCs can be generated from patients’ somatic cells and possess the potential to differentiate, under proper conditions, into any cell type. However, the clinical application of iPS cells is restricted because of their tumorigenic potential. Recent studies have indicated that stem cells exert their therapeutic benefit via a paracrine mechanism, and extracellular vesicles have been demonstrated that play a critical role in this paracrine mechanism. Due to lower immunogenicity, easier management, and presenting no risk of tumor formation, in recent years, researchers turned attention to exosomes as potential alternatives to whole‐cell therapy. Application of exosomes derived from iPSCs and their derived precursor provides a promising approach for personalized regenerative medicine. This study reviews the physiological functions of extracellular vesicles and discusses their potential therapeutic benefit in regenerative medicine.

Magnetic iron oxide nanoparticles are a well‐explored class of nanomaterials known for their high magnetization and biocompatibility. They have been used in various biomedical applications such as drug delivery, biosensors, hyperthermia, and magnetic resonance imaging (MRI) contrast agent. It is necessary to surface modify the nanoparticles with a biocompatible moiety to prevent their agglomeration and enable them to target to the defined area. Dendrimers have attracted considerable attention due to their small size, monodispersed, well‐defined globular shape, and a relative ease incorporation of targeting ligands. In this study, superparamagnetic iron oxide nanoparticles were synthesized via a coprecipitation method. The magnetic nanoparticles (MNPs) had been modified with (3‐aminopropyl) triethoxysilane, and then polyamidoamine functionalized MNPs had been synthesized cycling. Various characterization techniques had been used to reveal the morphology, size, and structure of the nanoparticles such as scanning electron microscopy, transmission electron microscope, X‐ray diffraction analysis, and vibrating sample magnetometer, Fourier‐transform infrared spectroscopy and zeta potential measurements. In addition, the cytotoxicity property of G3–dendrimer functionalized MNPs were evaluated using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2, 5‐diphenyl tetrazolium bromide assay which confirmed the biocompatibility of the nanocomposites. Dendrimer functionalized MNPs are able to act as contrast agents for MRI and magnetic fluid hyperthermia mediators. A superior heat generation was achieved for the given concentration according to the hyperthermia results. MRI results show that the synthesized nanocomposites are a favorable option for MRI contrast agent. We believe that these dendrimer functionalized MNPs have the potential of integrating therapeutic and diagnostic functions in a single carrier.

Mimicking the extracellular matrix to have a similar nanofibrous structure regarding electrical conductivity and mechanical properties would be highly beneficial for cardiac tissue engineering. The molybdenum disulfide, MoS 2 , and reduced graphene oxide, rGO, nanosheets are two-dimensional nanomaterials which can be considered as great candidates for enhancing the electrical and mechanical properties of biological scaffolds for cardiac tissue engineering applications. In this study, MoS 2 and rGO nanosheets were synthesized and incorporated into silk fibroin nanofibers, SF, via electrospinning method. Then, the human iPSCs transfected with TBX-18 gene, TBX18-hiPSCs, were seeded on these scaffolds for in vitro studies. The MoS 2 and rGO nanosheets were studied by Raman spectroscopy. After incorporation of the nanosheets into SF nanofibers, the associated characterizations were carried out including scanning electron microscopy, transmission electron microscopy, water contact angle, and mechanical test. Furthermore, SF, SF/MoS 2 , and SF/rGO scaffolds were used for in vitro studies. Herein, the scaffolds exhibited acceptable biocompatibility and considerable attachment to TBX18-hiPSCs confirmed by 3-(4, 5dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide, MTT, assay, and scanning electron microscopy. Also, the real-time PCR and immunostaining studies confirmed the maturity and upregulation of cardiac functional genes, including GATA-4, c-TnT, and α-MHC in the SF/MoS 2 and SF/rGO scaffolds compared with the bare SF one.Therefore, the reinforcement of these SF-based scaffolds with MoS 2 and rGO endues them as a suitable candidate for cardiac tissue engineering.

The function of fibroblast cells in wounded areas results in reconstruction of the extra cellular matrix and consequently resolution of granulation tissue. It is suggested that the use of platelet-rich plasma can accelerate the healing process in nonhealing or slow-healing wounds. In this study, a simple and novel method has been used to fabricate an electrospun three-layered scaffold containing plasma rich in growth factor with the aim of increasing the proliferation and migration of fibroblast cells in vitro. First, plasma rich in growth factor was derived from platelet rich plasma, and then a three-layered scaffold was fabricated using PLLA nanofibers as the outer layers and plasma rich in growth factor-containing gelatin fibers as the internal layer. The growth morphology of cells seeded on this scaffold was compared to those seeded on one layered PLLA scaffold. The study of the cell growth rate on different substrates and the migration of cells in response to the drug release of multilayered scaffold was investigated by the cell quantification assay and a modified under agarose assay. Scanning electron microscopy and fluorescence images showed that cells seeded on multilayered scaffold were completely oriented 72 hours after seeding compared to those seeded on PLLA scaffold. The cell quantification assay also indicated significant increase in proliferation rate of cells seeded on three-layered scaffold compared to those seeded on PLLA scaffold and finally, monitoring cell migration proved that cells migrate significantly toward the three-layered scaffold up to 48 to 72 hours and afterwards start to show a diminished migration rate toward this scaffold. K E Y W O R D S electrospinning, fibroblast migration, multilayered scaffolds, platelet rich plasma, skin tissue engineering

Mimicking the structure of extracellular matrix and electrical conductivity of myocardium are required to regenerate the functional cardiac tissue. In this study, Molybdenum disulfide, MoS2, nanosheets were synthesized and incorporated into nylon6 electrospun nanofibers in order to enhance the mechanical properties and electrical conductivity of the scaffolds. Then, the mouse embryonic cardiac cells, mECCs, were seeded on the scaffolds for in vitro studies. The MoS2 nanosheets were studied by scanning electron microscopy (SEM) and Raman spectroscopy. Nylon/MoS2 nanofibers were characterized by SEM, transmission electron microscopy (TEM), water contact angle measurement, electrical conductivity, and tensile test. Furthermore, cytocompatibility of scaffolds was confirmed by 3‐(4, 5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide, MTT, assay. SEM images showed more elongated morphology for mECCs attached to the nylon/MoS2 scaffold. Also, the Real‐Time PCR and immunostaining studies indicated the maturation and upregulation of cardiac functional genes including GATA‐4, c‐TnT, Nkx 2.5 and α‐MHC in the nylon/MoS2 scaffold in comparison to the bare nylon. Therefore, MoS2 reinforced nylon nanofibrous scaffolds can be considered as a suitable candidate in cardiac tissue engineering.