Wharton's Jelly Mesenchymal Stem Cells Research Articles

Cytokines secreted by mesenchymal stem cells reduce demyelination in an animal model of Charcot-Marie-Tooth disease

IntroductionDemyelinating Charcot-Marie-Tooth disease (CMT) is caused by mutations in the genes that encode myelinating proteins or their transcription factors. Our study thus sought to assess the therapeutic effects of cytokines secreted from mesenchymal stem cells (MSCs) on this disease. MethodsThe therapeutic potential of Wharton's jelly MSCs (WJ-MSCs) and cytokines secreted by WJ-MSCs was evaluated on Schwann cells (SCs) exhibiting demyelination features, as well as a mouse model of demyelinating CMT. ResultsCo-culture with WJ-MSC protected PMP22-overexpressing SCs from apoptotic cell death. Using a cytokine array, the secretion of growth differentiation factor-15 (GDF-15) and amphiregulin (AREG) was found to be elevated in WJ-MSCs when co-incubated with the PMP22-overexpressing SCs. Administration of both cytokines into trembler-J (Tr-J) mice, an animal model of CMT, significantly enhanced motor nerve conduction velocity compared to the control group. More importantly, this treatment alleviated the demyelinating phenotype of Tr-J mice, as demonstrated by an improvement in the mean diameter and g-ratio of the myelinated axons. ConclusionsOur findings demonstrated that WJ-MSCs alleviate the demyelinating phenotype of CMT via the secretion of several cytokines. Further elucidation of the underlying mechanisms of GDF-15 and AREG in myelination might provide a robust basis for the development of effective therapies against demyelinating CMT.

Wharton's jelly-derived stromal cells and their cell therapy applications in allogeneic haematopoietic stem cell transplantation.

For decades, mesenchymal stromal cells (MSCs) have been of great interest in the fields of regenerative medicine, tissue engineering and immunomodulation. Their tremendous potential makes it desirable to cryopreserve and bank MSCs to increase their accessibility and availability. Postnatally derived MSCs seem to be of particular interest because they are harvested after delivery without ethical controversy, they have the capacity to expand at a higher rate than adult‐derived MSCs, in which expansion decreases with ageing, and they have demonstrated immunological and haematological supportive properties similar to those of adult‐derived MSCs. In this review, we focus on MSCs obtained from Wharton's jelly (the mucous connective tissue of the umbilical cord between the amniotic epithelium and the umbilical vessels). Wharton's jelly MSCs (WJ‐MSCs) are a good candidate for cellular therapy in haematology, with accumulating data supporting their potential to sustain haematopoietic stem cell engraftment and to modulate alloreactivity such as Graft Versus Host Disease (GVHD). We first present an overview of their in‐vitro properties and the results of preclinical murine models confirming the suitability of WJ‐MSCs for cellular therapy in haematology. Next, we focus on clinical trials and discuss tolerance, efficacy and infusion protocols reported in haematology for GVHD and engraftment.

Nuclear magnetic resonance footprint of Wharton Jelly mesenchymal stem cells death mechanisms and distinctive in-cell biophysical properties in vitro.

The importance of the biophysical characterization of mesenchymal stem cells (MSCs) was recently pointed out for supporting the development of MSC‐based therapies. Among others, tracking MSCs in vivo and a quantitative characterization of their regenerative impact by nuclear magnetic resonance (NMR) demands a full description of MSCs’ MR properties. In the work, Wharton Jelly MSCs are characterized in a low magnetic field (LF) in vitro by using different approaches. They encompass various settings: MSCs cultured in a Petri dish and cell suspensions; experiments‐ 1D‐T 1, 1D‐T 2, 1D diffusion, 2D T 1‐T 2 and D‐T 2; devices‐ with a bore aperture and single‐sided one. Complex NMR analysis with the aid of random walk simulations allows the determination of MSCs T 1 and T 2 relaxation times, cells and nuclei sizes, self‐diffusion coefficients of the nucleus and cytoplasm. In addition, the influence of a single layer of cells on the effective diffusion coefficient of water is detected with the application of a single‐sided NMR device. It also enables the identification of apoptotic and necrotic cell death and changed diffusional properties of cells suspension caused by compressing forces induced by the subsequent cell layers. The study delivers MSCs‐specific MR parameters that may help tracking MSCs in vivo.

Improvement of Corneal Nerve Regeneration in Diabetic Rats Using Wharton's Jelly-Derived Mesenchymal Stem Cells and their Conditioned Medium.

To investigate the efficacy of Wharton's jelly mesenchymal stem cells (WJSCs) and their conditioned medium (CM) for corneal nerve regeneration in rats with diabetic keratopathy. Streptozotocin (STZ)-induced male diabetic (DM) rats (250-300 g) were divided into four groups (n=7/group): Control, DM, DM with WJSCs (DM+WJ), and DM with CM treatment (DM+CM). DM+WJ and DM+CM group received WJSCs or CM, respectively, topically with eye drops. Corneal sensibility, corneal epithelial layer integrity, histology, expression of GAP-43 and TUBB3 on mRNA level and their immunohistochemical expression were examined after two weeks of treatment. There were changes in corneal sensibility and corneal integrity between normal control and diabetic groups with/without WJSC or CM injection. Total central corneal thickness was significantly higher in DM+CM (249.81 ± 43.85 μm) than in control (174.72 ± 44.12 μm, P=0.004) and DM groups (190.15 ± 9.63 μm, P=0.03). GAP-43 mRNA expression levels of DM+WJ and DM+CM groups were higher compared with DM and control groups. TUBB3 mRNA level was increased after CM (P=0.047), but not after WJSCs treatment (P=1.00). GAP-43 and TUBB3 immunohistochemical expression of nerve fibers along the epithelial layer significantly increased in DM+WJ and DM+CM compared with DM group. Our findings showed that WJSCs and their CM improved corneal nerve regeneration in rats with diabetic keratopathy.

In Vivo Evaluation and Safety of the Wound-Healing Capability of Electrospun PCL/Gelatin Nanofibers Seeded with Wharton Jelly Mesenchymal Stem Cells

In Vivo Evaluation and Safety of the Wound-Healing Capability of Electrospun PCL/Gelatin Nanofibers Seeded with Wharton Jelly Mesenchymal Stem Cells

Novel Insights into the Stemness and Immune Privilege of Mesenchymal Stem Cells from Human Wharton Jelly by Single-Cell RNA Sequencing.

BackgroundFundamental and clinical interest in mesenchymal stem cells (MSCs) has risen dramatically over the past 3 decades. The immunomodulatory and differentiation abilities are the main mechanisms in vitro and in vivo. However, increasing evidence casts doubt on the stemness and immunogenicity of MSCs.Material/MethodsWe conducted a high-throughput 10x RNA sequencing and Smart-seq2 scRNA-seq analysis to reveal gene expression of Wharton jelly MSCs (WJ-MSCs) at a single-cell level. Multipotent differentiation, subpopulations, marker genes, human leucocyte antigen (HLA) gene expression, and cell cluster trajectory analysis were evaluated.ResultsThe WJ-MSCs had considerable heterogeneity between cells in terms of gene expression. They highly, partially, and hardly expressed genes related to mesodermal differentiation, endodermal differentiation, and ectodermal differentiation, respectively. Some cells seem to be bipotent or unipotent stem cells. Further, Monocle and cell cluster trajectory analysis demonstrated that 1 of the 3 divided clusters performed as stem cells, accounting for 12.6% of the population. The marker genes for a stem cell cluster were CRIM1, GLS, PLOD2, NEXN, ACTR2, FN1, MBNL1, LMOD1, COL3A1, NCL, SEC62, EPRS, COL5A2, COL8A1, and VCAN. In addition, the MSCs also highly, partially, and hardly expressed HLA-I antigen genes, HLA-II genes, and the HLA-G gene, respectively, indicating that MSCs probably have immunogenicity. A Kyoto Encyclopedia of Genes and Genomes pathway analysis of the 3 clusters demonstrated that they were mainly connected with viral infectious diseases, cancer, and endocrine and metabolic disorders. The most expressed transcription factors were zf-C2H2, HMG/HMGY, and Homeobox.ConclusionsWe found that only a subpopulation of WJ-MSCs are real stem cells and WJ-MSCs probably do not have immune privilege.

Potential of Human Neural Precursor Cells in Diabetic Retinopathy Therapeutics – Preclinical Model

ABSTRACTPurposeThis study aimed to evaluate a cell therapy strategy with human neural precursor cells (hNPCs) to treat diabetic retinopathy (DR) in Wistar rats induced to diabetes by injecting streptozotocin.Material and MethodsThe Wharton’s jelly mesenchymal stem cells (WJ-MSCs) were isolated, expanded, and seeded onto a biopolymer substrate to develop neurospheres and obtain the hNPCs. The animals were divided into three groups: non-diabetic (ND) n = four, diabetic without treatment (DM) n = nine, and diabetic with cell therapy (DM + hNPCs) n = nine. After 8 weeks of diabetes induction and DR characteristics installed, intravitreal injection of hNPCs (1 × 106 cell/µL) was performed in the DM + hNPCs group. Optical Coherence Tomography (OCT) and Electroretinography (ERG) evaluations were conducted before and during diabetes and after cell therapy. Four weeks posttreatment, histopathological and immunohistochemistry analyses were performed.ResultsThe repair of the retinal structures in the treated group (DM + hNPCs) was observed by increased thickness of neuroretinal layers, especially in the ganglion cell and photoreceptor layers, higher ERG oscillatory potentials (OPs) amplitudes, and transplanted hNPCs integration into the Retinal Pigment Epithelium.ConclusionsThe results indicate that hNPCs reduced DR progression by a neuroprotective effect and promoted retinal repair, making them potential candidates for regenerating the neuroretinal tissue.

Magnetic Nanoparticles and Magnetic Field Exposure Enhances Chondrogenesis of Human Adipose Derived Mesenchymal Stem Cells But Not of Wharton Jelly Mesenchymal Stem Cells.

Purpose: Iron oxide based magnetic nanoparticles (MNP) are versatile tools in biology and medicine. Adipose derived mesenchymal stem cells (ADSC) and Wharton Jelly mesenchymal stem cells (WJMSC) are currently tested in different strategies for regenerative regenerative medicine (RM) purposes. Their superiority compared to other mesenchymal stem cell consists in larger availability, and superior proliferative and differentiation potential. Magnetic field (MF) exposure of MNP-loaded ADSC has been proposed as a method to deliver mechanical stimulation for increasing conversion to musculoskeletal lineages. In this study, we investigated comparatively chondrogenic conversion of ADSC-MNP and WJMSC with or without MF exposure in order to identify the most appropriate cell source and differentiation protocol for future cartilage engineering strategies. Methods: Human primary ADSC and WJMSC from various donors were loaded with proprietary uncoated MNP. The in vitro effect on proliferation and cellular senescence (beta galactosidase assay) in long term culture was assessed. In vitro chondrogenic differentiation in pellet culture system, with or without MF exposure, was assessed using pellet histology (Safranin O staining) as well as quantitative evaluation of glycosaminoglycan (GAG) deposition per cell. Results: ADSC-MNP complexes displayed superior proliferative capability and decreased senescence after long term (28 days) culture in vitro compared to non-loaded ADSC and to WJMSC-MNP. Significant increase in chondrogenesis conversion in terms of GAG/cell ratio could be observed in ADSC-MNP. MF exposure increased glycosaminoglycan deposition in MNP-loaded ADSC, but not in WJMSC. Conclusion: ADSC-MNP display decreased cellular senescence and superior chondrogenic capability in vitro compared to non-loaded cells as well as to WJMSC-MNP. MF exposure further increases ADSC-MNP chondrogenesis in ADSC, but not in WJMSC. Loading ADSC with MNP can derive a successful procedure for obtaining improved chondrogenesis in ADSC. Further in vivo studies are needed to confirm the utility of ADSC-MNP complexes for cartilage engineering.

Development of injectable graphene oxide/laponite/gelatin hydrogel containing Wharton's jelly mesenchymal stem cells for treatment of oxidative stress-damaged cardiomyocytes

In the initial stage of myocardial infarction (MI), cardiomyocyte necrosis activates aninflammatory response and increases the reactive oxygen species (ROS) content. Graphene oxide (GO) possesses potential antioxidant properties and can provide the adequate mechanical support for cell growth. The clinical studies showed that direct injection of Wharton's jelly mesenchymal stem cells (WJ-MSCs) into infarcted areas of myocardium can reduce apoptosis and fibrosis. Gelatin is a natural polymer and can promote cell attachment. Nanoclay laponite with shear-thinning properties can be injected and gelled in-situ without chemical triggers. In the study, injectable GO/laponite/gelatin (GO-LG) hydrogel was developed and characterized. The results of cell viability showed that the optimal concentration of GO flasks (200 to 300 nm) to treat cells was 100 μg/ml. Addition of nanosized GO to the laponite/gelatin (LG) hydrogel could increase the mechanical strength and have both hemocompatibility and cytocompatibility. The release of GO from LG hydrogel could inhibit the H2O2-induced oxidative stress. The GO-LG hydrogel containing WJ-MSCs could decrease inflammation and apoptosis level and increase the cell viability of cardiomyocytes under oxidative stress. We believe that utilizing this newly developed GO-LG hydrogel containing WJ-MSCs may have potential applications in the future for treatment of MI.

A new perfusion mode of culture for WJ-MSCs expansion in a stirred and online monitored bioreactor.

Asa clinical dose requires a minimum of 106 cells per kilogram of patients, it is, therefore, crucial to develop a scalable method of production of Wharton Jelly mesenchymal stem cells (WJ-MSCs) with maintained inner characteristics. Scalable expansion of WJ-MSCs on microcarriers usually found in cell culture, involvesspecific cell detachment using trypsin and could have harmful effects on cells. In this study,the performance of batch, fed-batch, and perfused-continuous mode of culture were compared. The batch and fed-batch modes resulted in expansion factors of 5 and 43, respectively. The perfused-continuous mode strategy consisted of the implementation of a settling tube inside the bioreactor. The diameter of the tube was calculated to maintain microcarriers colonized by cells in the bioreactor whereas empty microcarriers (responsible for potentially damaging collisions) were removed, using a continuous flow rate based on MSCs physiological requirements. Thanks to this strategy, a maximal number of 800 million cells was obtained in a 1.5 L bioreactor in 10 days. Lastly, online dielectric spectroscopy was implemented in the bioreactor and indicated that cell growth could be monitored during the culture.

Pre-vascularization of biomimetic 3-D scaffolds via direct co-culture of human umbilical cord derived osteogenic and angiogenic progenitor cells

A major barrier in the bone tissue-engineered construct (TEC) is the nonexistence of a vasculature system, which compromises the survival of the transplanted cells and limits their clinical use. The current work aimed at developing pre-vascularized functional constructs by direct co-culture of human Wharton's jelly mesenchymal stem cells (WJ-MSCs) and human umbilical vein endothelial cells (HUVECs) on 3-D biomimetic nano-hydroxyapatite/chitosan/gelatin (nHA/Cs/Gel) scaffolds. Cells were seeded in mono- and co-culture circumstances for over 3 weeks. Cell morphology and attachment, differentiation, proliferation, and formation of the capillary-like structure were assessed by different histomorphological, biochemical, and molecular tests at specific time points. As shown by SEM, H&E, and DAPI staining, cells adhered and spread well onto scaffold surfaces. Mineralization and ALP activity in co-cultured cells were higher significantly compared to those of monocultures. This activity also was found to be concurrent with the upregulation of osteogenic and angiogenic-related markers at the gene and protein levels at selected time points. Moreover, based on the results of IHC staining, the co-culture system favored the formation of a vessel-like structure. Overall, our novel approach of co-culturing two types of cells with the same origin (i.e., WJ-MSCs and HUVECs) resulted in pre-vascularized 3-D nHA/Cs/Gel scaffolds and tailored them to future clinical requirements.

Effect of low dose ionizing radiation versus human wharton’s jelly mesenchymal stem cells in the treatment of experimental rheumatoid arthritis

Rheumatoid arthritis (RA) is one of the major causes of disability that aggrieve a financial burden for the healthcare system as well as for patients. Both stem cell therapy and low-dose radiotherapy (LD-RT) have been recognized as alternative approaches to alleviate pain, inflammation, and bone in the inflamed joints. Accordingly, the present study was designed to compare the efficacy of both modalities in the treatment of RA in experimental rats. Rheumatoid arthritis was induced in forty female rats using Complete Freund’s adjuvant (CFA), divided into four groups (arthritic induction group and three treatment groups) compared to controls: one of the treatment groups received Human’s Wharton Jelly Mesenchymal Stem Cells (WJMSC), and the other two groups received individual doses of 0.5 and 1 Gy of Gamma irradiation once a week for six weeks. After six weeks animals were sacrificed and examined for joint histology, paw swelling, mRNA gene expression for TNF-α, IL-1β and IL-6 together with serum anticyclic citrullinated peptide (anti-CCP) and nitric oxide (NO). Results showed that both doses of (0.5 Gy and 1 Gy) and WJMSC individually modulated RA effects by significantly decreasing the measured biochemical and molecular parameters. However, at the histology level it was evident that irradiation has a better pronounced effect compared to WJMSC, which showed aggravated effects on joint erosion. The present study reports that both IR and WJMSC significantly decreased Anti-CCP, which is a specific marker for RA, however, WJMSC might have deliberate effects on the synovitis and arthritis.

A Two-Stage Process for Differentiation of Wharton's Jelly-Derived Mesenchymal Stem Cells into Neuronal-like Cells.

With no permanent cure for neurodegenerative diseases, the symptoms reappear shortly after the withdrawal of medicines. A better treatment outcome can be expected if the damaged neurons are partly replaced by functional neurons and/or they are repaired using trophic factors. In this regard, safe cell therapy has been considered as a potential alternative to conventional treatment. Here, we have described a two-stage culture process to differentiate Wharton Jelly mesenchymal stem cells (WJ-MSCs) into neuronal-like cells in the presence of various cues involved in neurogenesis. The fate of cells at the end of each stage was analyzed at the morphometric, transcriptional, and translational levels. In the first stage of priming, constitutively, wingless-activated WJ-MSCs crossed the lineage boundary in favor of neuroectodermal lineage, identified by the loss of mesenchymal genes with concomitant expression of neuron-specific markers, like SOX1, PAX6, NTRK1, and NEUROD2. Neuronal-like cells formed in the second stage expressed many mature neuronal proteins like Map2, neurofilament, and Tuj1 and possessed axon hillock-like structures. In conclusion, the differentiation of a large number of neuronal-like cells from nontumorigenic and trophic factors secreting WJ-MSCs promises the development of a therapeutic strategy to treat neurodegenerative diseases.

Effect of dermal fibroblasts and mesenchymal stem cells seeded on an amniotic membrane scaffold in skin regeneration: A case series

Skin wound healing has always been a challenging subject as it involves the coordinated functioning of various cells and molecules. Any disorder in wound healing can cause healing failure and result in chronic wounds. In this study, we hypothesized that co-cultured dermal fibroblasts (DFs) and Wharton's jelly mesenchymal stem cells (WJ-MSCs) seeded on an acellular amniotic membrane scaffold could be used to promote skin regeneration in chronic ulcers. In this case series, the chronic wounds of five diabetic patients aged between 30 and 60 years were treated with co-cultured WJ-MSCs and DFs seeded on an acellular amniotic membrane. Treatment was applied and the wound healing process was evaluated every three days for nine days, with the patients being subsequently followed up for one month. The wound healing percentage, time taken for the wound to heal, and wound size were monitored. The mean wound healing rate (WHR) increased progressively in all lesions. The mean percentage of wound healing after transplantation of the biological scaffold enriched with WJ-MSCs and autologous DFs after treatment was 93.92 %, respectively. The healing percentage significantly increased after three days; significant decreases in wound size and healing time were recorded after six and nine days of treatment, respectively (P < 0.002), and Total skin regeneration and re-epithelialization were achieved by the ninth day of treatment. There were no side effects or complications. Given the current problems and complications presented by chronic wounds, Novel Clinical approaches involving cell therapy and tissue engineering can be regarded as an attractive therapeutic option for the treatment of chronic and difficult-to-heal wounds.

In Vitro Activation and Development of Goat Preantral Follicles Enclosed in Ovarian Tissue Co-cultured with Mesenchymal Stem Cells.

The development of culture systems capable of maintaining follicular growth since the preantral stage has been the target of investigations. Mesenchymal stem cells (MSC) present potential for use in a wide range of applications, including research aimed at preserving fertility. Therefore, this study investigated the use of caprine Wharton's Jelly Mesenchymal Stem Cells (WJMSC) on the survival and in vitro development of goat preantral follicles enclosed in ovarian fragments cultured for 1 or 7days. Fragments of the ovarian cortex were immediately fixed (non-cultured control) or distributed in four treatments: ovarian tissue cultured in control medium (α-MEM+); ovarian tissue cultured in α-MEM+ supplemented with FBS (α-MEM+ + FBS); ovarian tissue co-cultured with stem cells in α-MEM+ (α-MEM+ + SC); and ovarian tissue co-cultured with stem cell in α-MEM+ + FBS (α-MEM+ + SC + FBS). The rates of cell proliferation, follicular survival, and activation, as well as follicular diameter, were evaluated. After 7days, the treatment co-cultured with stem cells showed a higher (P < 0.05) percentage of morphologically normal preantral follicles compared to the other treatments, as well as a higher (P < 0.05) activation rate compared to cultured control. Moreover, the follicular diameter was higher (P < 0.05) in the treatment co-cultured with stem cells compared to co-cultured with stem cells plus FBS. This study demonstrates for the first time that in vitro co-culture of caprine WJMSC with preantral follicles enclosed in goat ovarian tissue improves activation and early follicular development.

Pre-conditioning of Mesenchymal Stem Cells with Piper longum L. augments osteogenic differentiation

Ethnopharmacological relevanceThe Indian Traditional Medicine, Ayurveda prescribes Piper longum L. popularly known as Long Pepper (Pippali) for the treatment of inflammatory and degenerative diseases. Therapeutic benefits of Piper longum L. are mainly attributed to the anti-inflammatory and arthritic potential. Aim of the studyThis study was aimed to explore the activity of Piper longum L. fruit extract on proliferation and osteogenic differentiation of human Wharton's Jelly Mesenchymal Stem Cells (WJMSCs) to find out it's possible role as anti-osteoporotic agent. Materials and methodsProliferation of WJMSCs treated with Piper longum L. fruit extract was assessed by MTT assay and Cell Cycle Analysis. Effect of Piper longum L. preconditioning on osteogenic differentiation was performed. Ca2+ accumulation and matrix mineralization (Von Kossa and Alizarin Red Staining), alkaline phosphatase (ALP) activity and gene expression of key mRNA (RT PCR) was analyzed. ResultsSignificant increase in the proliferation of WJMSCs was observed upon treatment of Piper longum L. at 5 μg/mL (P < 0.001) which can be attributed to the significant decrease in apoptotic cells (P < 0.05) as evidenced by cell cycle analysis. Preconditioning of Piper longum L. (10–100 μg/mL) enhanced Ca2+ accumulation and matrix mineralization as observed by Von Kossa and Alizarin Red staining where ALP activity was elevated 3.6 folds as compared to untreated WJMSCs (P < 0.001). RT-PCR analysis exhibited up regulation of Runx2, Osterix, ALP and OPN mRNAs. ConclusionsWe demonstrate for the first time that Piper longum L. fruit extract enhanced osteogenic differentiation of WJMSCs. This finding can be clinically translated into development of an anti-osteoporotic agent.

The synergistic effects of quercetin-containing 3D-printed mesoporous calcium silicate/calcium sulfate/poly-ε-caprolactone scaffolds for the promotion of osteogenesis in mesenchymal stem cells

Several growth factors were proven to be effective in the treatment of bone defects and fractures and thus have great potential for bone regeneration applications. However, it needs low-temperature storage and transportation. This study aimed to investigate the herbal extract quercetin, a candidate for natural flavonoid compounds that have been reported to be involved in regulating inflammation and improving immunity and health. In this study, we prepared quercetin (Q)/mesoporous calcium silicate calcium sulfate (MSCS)/polycaprolactone (PCL) composite scaffolds using the 3D printing technique, where we immersed it in simulated body fluid (SBF) solution and soaked it for up to 60 days. The characteristics of quercetin scaffold were examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), immunofluorescence, and Alizarin Red S staining. We found precipitation of apatite on the surface of the scaffold. The invitro results for cell proliferation, cytotoxicity, and immunofluorescence staining revealed that Wharton's jelly mesenchymal stem cells (WJMSCs) with a 2% quercetin (Q2) scaffold were significantly higher in number than with 1% quercetin (Q1) and MSCS scaffolds. The phalloidin staining of cell skeletons on the surface of Q2 revealed powerful cell-to-cell adhesion and high expression of green fluorescence. The Q2 scaffold also had the highest calcium deposit levels based on Alizarin Red S staining in all scaffolds. This indicated that quercetin was able to induce cell growth and mitosis, echoing the previous preliminary results. Our initial results indicate that this natural herbal extract can be a good bone-based gene substitution for bone regeneration.

Effect of Sulfur on Nitrogen-Containing Plasma Polymers in Promoting Osteogenic Differentiation of Wharton’s Jelly Mesenchymal Stem Cells

The role of sulfur and its synergistic effects with nitrogen moieties in mediating stem cell proliferation and differentiation has become of interest to the tissue engineering community due to chemical similarities with the glycosaminoglycans found in human tissues and cells. Glycosaminoglycans are biomolecules known to influence stem cell differentiation, but the roles of sulfur with different oxidation states on nitrogen-containing polymers have not been fully understood nor investigated. In this study, we used the plasma polymerization of 1,7-octadiene (ppOD), n-heptylamine (ppHA), ppHA grafted with vinyl-sulfonate via Michael-type addition (ppHA-SO3), thiophene (ppT), and ppT with air plasma treatment (ppT-air) to produce controlled amounts of nitrogen and sulfur moieties having different oxidation states, as confirmed by x-ray photoelectron spectroscopy. Assays of the proliferation and osteogenic activities of Wharton’s jelly mesenchymal stem cells (WJ-MSCs) showed the highest activities for ppHA, followed by ppHA-SO3, due to high percentages of amines/amides and the absence of SO3 moieties in ppHA. Other plasma polymers showed less proliferation and osteogenic differentiation than the positive control (glass substrate); however, WJ-MSCs grown on ppT-air with its high percentages of SO4 displayed cytoskeletons intensified with actin stress fiber, unlike the thiol-dominated ppT. Finally, the presence of methyl groups in ppOD severely limited WJ-MSCs proliferation and differentiation. Overall, these results confirm the beneficial effects of amine/amide groups on WJ-MSCs proliferation and osteogenic differentiation, but the combination of these groups with sulfur of various oxidation states failed to further enhance such cellular activities.

Characterization and plasticity of wharton's jelly mesenchymal stem cells of goat

Mesenchymal stem cells (MSCs), obtained from several anatomical sites, have already been described, characterized and used in therapeutic models for tissue repair. The umbilical cord mesenchymal stem cells, represented by cells from arteries and veins walls, as well as Wharton's jelly are easy to be obtained, highly available, require no invasive procedure, do not present risk to donors and do not present ethical limitation. The aim of this research was to analyze the plasticity of Wharton's jelly mesenchymal stem cells (WJ-MSCs) of goat, evaluating their behavior in vitro and characterizing them immunophenotypically. Thus, tests were performed on colony forming units, viability and cell growth curve, flow cytometry analysis and plasticity potential. Goat umbilical cord matrix cells exhibited fibroblastoid morphology with colony formation and self-renewal ability, always maintaining their undifferentiated state up to the eighth passage (P8). The growth curve kinetics exhibited the LAG, LOG, and DECAY phases, without displaying a PLATEAU phase. The plasticity assay demonstrated positive differentiation for osteogenic, adipogenic and chondrogenic lines, characterized by the synthesis of intracytoplasmic granules or extracellular matrix with the presence of calcium, lipids and proteoglycans. Flow cytometry demonstrated the expression of CD90 and CD105; absence of CD14 expression. It is concluded that the cell population isolated from the Wharton's jelly of goat constitutes a representative sample of mesenchymal stem cells, with great possibilities in the field of regenerative and reproductive medicine.

Muscle functional recovery is driven by extracellular vesicles combined with muscle extracellular matrix in a volumetric muscle loss murine model

Biological scaffolds derived from decellularized tissues are being investigated as a promising approach to repair volumetric muscle losses (VML). Indeed, extracellular matrix (ECM) from decellularized tissues is highly biocompatible and mimics the original tissue. However, the development of fibrosis and the muscle stiffness still represents a major problem. Intercellular signals mediating tissue repair are conveyed via extracellular vesicles (EVs), biologically active nanoparticles secreted by the cells. This work aimed at using muscle ECM and human EVs derived from Wharton Jelly mesenchymal stromal cells (MSC EVs) to boost tissue regeneration in a VML murine model. Mice transplanted with muscle ECM and treated with PBS or MSC EVs were analyzed after 7 and 30 days. Flow cytometry, tissue analysis, qRT-PCR and physiology test were performed. We demonstrated that angiogenesis and myogenesis were enhanced while fibrosis was reduced after EV treatment. Moreover, the inflammation was directed toward tissue repair. M2-like, pro-regenerative macrophages were significantly increased in the MSC EVs treated group compared to control. Strikingly, the histological improvements were associated with enhanced functional recovery. These results suggest that human MSC EVs can be a naturally-derived boost able to ameliorate the efficacy of tissue-specific ECM in muscle regeneration up to the restored tissue function.