Production of hepatocyte-like cells from human umbilical vein mesenchymal stem cells

The human umbilical vein, as a readily available stem cell source, is a good alternative to harvest mesenchymal stem cells. Human umbilical cord vein mesenchymal stem cells have recently been isolated and have demonstrated the ability to differentiate into various cell types such as fat, bone, cartilage and neuronal cells. In this study, we have investigated whether human umbilical cord vein mesenchymal stem cells are also able to differentiate into hepatocyte-like cells. Hepatic differentiation was performed with a 2-step protocol and the use of hepatocyte growth factor and oncostatin M for cell culture. During four weeks of induction, most cells displayed a cuboidal morphology. Immunological analysis indicated that umbilical cord vein mesenchymal stem cells-derived hepatocyte-like cells expressed liver-specific protein markers such as albumin and cytokeratin-18. The hepatocyte-like cells also displayed several characteristics of hepatocytes, including expression of transthyretin, glucose 6-phosphatase, cytokeratin-8,18, alpha-fetoprotein, hepatocyte nuclear factor-3β and albumin. The result of indocyanine green cell uptake, as a test substance to evaluate hepatocyte-like cell function, was positive for differentiated cells. Glycogen storage was examined by periodic acid-Schiff staining. Accumulation of intracellular glycogen was detected in the hepatocyte-like cells. Based on these observations, we have concluded that umbilical cord vein mesenchymal stem cells are endowed with hepatogenic potential and may provide a stem cell source to be used as cell therapy for liver diseases

Fabrication and characterization of nanofibrous scaffold based on chitosan containing cerium oxide nanoparticles for wound healing application

Hypothesis: Incorporating different types of nanoparticles, especially metal oxide nanoparticles, into the polymeric nanofiber substrate improves different properties of the web. In this research, citric acid is used as an environmentally friendly cross-linking agent to reduce the hydrophilic property of chitosan-polyvinyl alcohol web. Cerium oxide nanoparticles (nanoceria) as an antioxidant and antibacterial agent are used to increase the biological capabilities of the web for healing applications.Methods: Chitosan (CS)/poly(vinyl alcohol) (PVA)/citric acid (CA) nanofibers with the mass ratios of 1:1:0.5 and 2:3:1 (CS:PVA:CA) were prepared and electrospun. Nanoceria was loaded into the optimal blend prepared for electrospinning. In continuation, the physical-morphological properties, cell compatibility, non-cytotoxicity, and antibacterial activity of the resulting webs were investigated.Findings: Physical-morphological investigations show that the CS:PVA:CA (2:3:1) nanofiber which was electrospun under 15 kV and 18 cm is the optimal nanofiber with an average diameter of 175±29 nm. The contact angle is about 42 degrees, indicating a suitable decrease in hydrophilicity and maintaining the physical integrity of the web. The SEM images show a bead-less morphology with an average diameter of 274±38 nm for nanofibrous web containing 1.5% (by wt) CeO2. The presence of nanoceria and interactions of the functional groups in the components were evident in their EDS and FTIR spectra, respectively. The results of the cell-culturing demonstrate the proper growth and proliferation of fibroblast cells on both with and without-nanoceria webs. The result of the MTT test confirms the non-toxicity of both scaffolds. The antibacterial investigations show improvements in antibacterial activities of the nanofibers containing cerium-oxide against both gram-positive and gram-negative bacteria. In general, the results determined that the presence of nanoceria in chitosan-polyvinyl-alcohol-citric acid electrospun nanofibers has clearly improved the biological properties, especially the antibacterial behavior of the obtained web, so it can be used as a suitable dressing for wound healing application