Mesenchymal Stromal Cells Research Papers (original) (raw)

Human mesenchymal stem/stromal cells (hMSCs) have been shown to support breast cancer cell proliferation and metastasis, partly through their secretome. hMSCs have a remarkable ability to survive for long periods under stress, and their secretome is tumor supportive. In this study, we have characterized the cargo of extracellular vesicular (EV) fraction (that is in the size range of 40-150nm) of serum deprived hMSCs (SD-MSCs). Next Generation Sequencing assays were used to identify small RNA secreted in the EVs, which indicated presence of tumor supportive miRNA. Further assays demonstrated the role of miRNA-21 and 34a as tumor supportive miRNAs. Next, proteomic assays revealed the presence of ≈150 different proteins, most of which are known tumor supportive factors such as PDGFR-β, TIMP-1, and TIMP-2. Lipidomic assays verified presence of bioactive lipids such as sphingomyelin. Furthermore, metabolite assays identified the presence of lactic acid and glutamic acid in EVs. The co-injection xenograft assays using MCF-7 breast cancer cells demonstrated the tumor supportive function of these EVs. To our knowledge this is the first comprehensive -omics based study that characterized the complex cargo of extracellular vesicles secreted by hMSCs and their role in supporting breast cancers.

- by and +1
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- Tumor microenvironment, Mice, Osteosarcoma, Lipid metabolism

We have recently reported that human fallopian tubes, which are discarded during surgical procedures of women submitted to sterilization or hysterectomies, are a rich source of human fallopian tube mesenchymal stromal cells (htMSCs). It has been previously shown that human mesenchymal stromal cells may be useful in enhancing the speed of bone regeneration. This prompted us to investigate whether htMSCs might be useful for the treatment of osteoporosis or other bone diseases, since they present a pronounced capacity for osteogenic differentiation in vitro. Based on this prior knowledge, our aim was to evaluate, in vivo, the osteogenic capacity of htMSCs to regenerate bone through an already described xenotransplantation model: nonimmunosuppressed (NIS) rats with cranial defects. htMSCs were obtained from five 30-50 years old healthy women and characterized by flow cytometry and for their multipotenciality in vitro capacity (osteogenic, chondrogenic and adipogenic differentiations). Two symmetric fullthickness cranial defects on each parietal region of seven NIS rats were performed. The left side (LS) of six animals was covered with CellCeram (Scaffdex)-a bioabsorbable ceramic composite scaffold that contains 60% hydroxyapatite and 40% β-tricalciumphosphate-only, and the right side (RS) with the CellCeram and htMSCs (10 6 cells/scaffold). The animals were euthanized at 30, 60 and 90 days postoperatively and cranial tissue samples were taken for histological analysis. After 90 days we observed neobone formation in both sides. However, in animals euthanized 30 and 60 days after the procedure, a mature bone was observed only on the side with htMSCs. PCR and immunofluorescence analysis confirmed the presence of human DNA and thus that human cells were not rejected, which further supports the imunomodulatory property of htMSCs. In conclusion, htMSCs can be used successfully to enhance bone regeneration in vivo, opening a new field for future treatments of osteoporosis and bone reconstruction.

- by Tatiana Jazedje
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- Hydroxyapatite, Flow Cytometry, Biology, Medicine

Introduction: Based on the positive results observed in experimental animal models, adipose tissue-derived mesenchymal stem cells (AD-MSCs) constitute a promising therapy for stroke treatment. However, several aspects need to be clarified to identify the optimal conditions for successful clinical translation. Areas covered: This review focuses on AD-MSC treatment for ischemic and hemorrhagic stroke in experimental animal models. In addition, we will explore the optimization of treatment conditions including AD-MSC production, administration routes and therapeutic windows for their appropriate use in patients, and we will provide an update on clinical trials on this therapy. Expert opinion: Compared with other cell types, AD-MSCs have been less investigated in stroke studies. Currently, experimental animal models have shown safety and efficacy with this treatment after stroke. Due to several advantages of AD-MSCs, such as their abundance and accessibility, they can be considered a promising strategy for use in patients. However, many questions are still to be resolved regarding their mechanisms of action, immune system modulation and the effects of AD-MSCs on all components of the brain that may be affected after ischemic and hemorrhagic strokes.

- by María Gutiérrez-Fernández
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- Medicine, Adipose tissue, Mesenchymal stem cells, Stroke

Bioreactors provide a dynamic culture system for efficient exchange of nutrients and mechanical stimulus necessary for the generation of effective tissue engineered bone grafts (TEBG). We have shown that biaxial rotating (BXR) bioreactor-matured human fetal mesenchymal stem cell (hfMSC) mediated-TEBG can heal a rat critical sized femoral defect. However, it is not known whether optimal bioreactors exist for bone TE (BTE) applications. We systematically compared this BXR bioreactor with three most commonly used systems: Spinner Flask (SF), Perfusion and Rotating Wall Vessel (RWV) bioreactors, for their application in BTE. The BXR bioreactor achieved higher levels of cellularity and confluence (1.4e2.5x, p < 0.05) in large 785 mm 3 macroporous scaffolds not achieved in the other bioreactors operating in optimal settings. BXR bioreactor-treated scaffolds experienced earlier and more robust osteogenic differentiation on von Kossa staining, ALP induction (1.2e1.6Â, p < 0.01) and calcium deposition (1.3 e2.3Â, p < 0.01). We developed a Micro CT quantification method which demonstrated homogenous distribution of hfMSC in BXR bioreactor-treated grafts, but not with the other three. BXR bioreactor enabled superior cellular proliferation, spatial distribution and osteogenic induction of hfMSC over other commonly used bioreactors. In addition, we developed and validated a non-invasive quantitative micro CT-based technique for analyzing neo-tissue formation and its spatial distribution within scaffolds.

- by Swee Teoh
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- Materials Science, Biomaterials, Cell Adhesion, Medicine

Physiochemical properties of biomaterials play critical roles in dictating types of cell behaviour. In this study, a series of poly(ε-caprolactone) (PCL)-derived polymers bearing different small chemical groups was employed as a platform to evaluate chondrogenesis of different cell types. Thin films were prepared by spin-coating PCL derivatives. Rabbit articular chondrocytes (rACs) and rabbit bone marrow-derived mesenchymal stem cells (rMSCs) were seeded on to the films, and cell adhesion, proliferation, extracellular matrix production and gene expression were evaluated. The presence of hydrophilic groups (-NH2 , -COOH, -OH and -C=O) promoted adhesion and proliferation of primary rACs and rMSCs. On these polymeric films, chondrogenesis of primary rACs depended on culture time. For passaged cells, re-differentiation was induced on these films by chondrogenic induction, but less for cells of passage 5 compared to passage 3. While films with hydrophilic groups favoured chondrocytic gen...

- by Wen-song Tan
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- Chemistry, Cell Adhesion, Medicine, Extracellular Matrix

Diabetes mellitus type 1 is a form of diabetes mellitus that results from the autoimmune destruction of insulin-producing beta cells in the pancreas. The current gold standard therapy for pancreas transplantation has limitations because of the long list of waiting patients and the limited supply of donor pancreas. Mesenchymal stem cells (MSCs), a relatively new potential therapy in various fields, have already made their mark in the young field of regenerative medicine. Recent studies have shown that the implantation of MSCs decreases glucose levels through paracrine influences rather than through direct transdifferentiation into insulin-producing cells. Therefore, these cells may use pro-angiogenic and immunomodulatory effects to control diabetes following the cotransplantation with pancreatic islets. In this review, we present and discuss new approaches of using MSCs in the treatment of diabetes mellitus type 1.

- by Jana Katuchova
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- Medicine, Cell Differentiation, Clinical Sciences, Endocrine pathology

We generated, on titanium surfaces, self-assembled layers of vertically oriented TiO 2 nanotubes with defined diameters between 15 and 100 nm and show that adhesion, spreading, growth, and differentiation of mesenchymal stem cells are critically dependent on the tube diameter. A spacing less than 30 nm with a maximum at 15 nm provided an effective length scale for accelerated integrin clustering/focal contact formation and strongly enhances cellular activities compared to smooth TiO 2 surfaces. Cell adhesion and spreading were severely impaired on nanotube layers with a tube diameter larger than 50 nm, resulting in dramatically reduced cellular activity and a high extent of programmed cell death. Thus, on a TiO 2 nanotube surface, a lateral spacing geometry with openings of 30−50 nm represents a critical borderline for cell fate.

- by Patrik Schmuki
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- Titanium, Apoptosis, Multidisciplinary, Nanostructures

The past decade has witnessed an upsurge in studies demonstrating mitochondrial transfer as one of the emerging mechanisms through which mesenchymal stem cells (MSCs) can regenerate and repair damaged cells or tissues. It has been found to play a critical role in healing several diseases related to brain injury, cardiac myopathies, muscle sepsis, lung disorders and acute respiratory disorders. Several studies have shown that various mechanisms are involved in mitochondrial transfer that includes tunnel tube formation, micro vesicle formation, gap junctions, cell fusion and others modes of transfer. Few studies have investigated the mechanisms that contribute to mitochondrial transfer, primarily comprising of signaling pathways involved in tunnel tube formation that facilitates tunnel tube formation for movement of mitochondria from one cell to another. Various stress signals such as release of damaged mitochondria, mtDNA and mitochondrial products along with elevated reactive oxygen...

- by Swati Paliwal
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- Regeneration, Biology, Mitochondria, Medicine

Therapeutic strategies for the fatal neurodegenerative disease amyotrophic lateral sclerosis (ALS) are actually minimally effective on patients' survival and quality of life. Although stem cell therapy has raised great expectations, information on the involved molecular mechanisms is still limited. Here we assessed the efficacy of the systemic administration of adipose-derived mesenchymal stem cells (ASC), a previously untested stem cell population, in superoxide-dismutase 1 (SOD1)-mutant transgenic mice, the animal model of familial ALS. The administration of ASC to SOD1-mutant mice at the clinical onset significantly delayed motor deterioration for 4-6 weeks, as shown by clinical and neurophysiological tests. Neuropathological examination of ASC-treated SOD1-mutant mice at day 100 (i.e. the time of their best motor performance) revealed a higher number of lumbar motorneurons than in phosphate-buffered saline-treated SOD1-mutant mice and a restricted number of undifferentiated ...

- by Ilaria Scambi and +1
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- Neuroscience, Psychology, Amyotrophic Lateral Sclerosis, Neurotrophins
- by Jan D Huizinga
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- Electron Microscopy, Gap Junctions, Pancreas, Prostate
- by mesut tez
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- Stem Cell, Fascia, Inguinal Hernia, Tensile Strength

The mechanisms of idiopathic severe aplastic anemia (SAA) in children are not completely understood. Insufficiency of the bone marrow microenvironment, in which mesenchymal stem cells (MSCs) are an important element, can be a potential factor associated with hematopoietic impairment. In the current study, we studied whether aberrant gene expression could be found in MSCs from children with SAA. Using microarray analysis, two different patterns of global gene expression were detected in the SAA MSCs. Fourteen genes (POLE2, HGF, KIF20A, TK1, IL18R1, KITLG, FGF18, RRM2, TTK, CXCL12, DLG7, TOP2A, NUF2, and TYMS), which are related to DNA synthesis, cytokines, or growth factors, were significantly downregulated. Further, knockdown of gene expression was performed using the small hairpin RNA (shRNA)-containing lentivirus method. We found that knockdown of CXCL12, HGF, IL-18R1, FGF18, or RRM2 expression compelled MSCs from the controls to behave like those from the SAA children, with decreased survival and differentiation potential. Among them, inhibition of CXCL12 gene expression had the most profound effects on the behavior of MSCs. Further experiments regarding re-introduction of the CXCL12 gene could largely recover the survival and differentiation potential in MSCs with inhibition of CXCL12 expression. Our findings suggest that MSCs from children with SAA exhibit aberrant gene expression profiles and downregulation of CXCL12 gene may be associated with alterations in the bone marrow microenvironment.

- by Kuan-Chih Chow and +1
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- Adolescent, Child, Mesenchymal Stromal Cells, Gene Expression Regulation

The bone marrow contains mesenchymal stem cells (MSCs) that differentiate to the osteogenic and adipogenic lineages. The fact that the decrease in bone volume of age-related osteoporosis is accompanied by an increase in marrow adipose tissue implies the importance that the adipogenic process may have in bone loss. We previously observed that MSCs from control and osteoporotic women showed differences in their capacity to differentiate into the osteogenic and adipogenic pathways. In vitro studies indicate that bone marrow stromal cells are responsive to leptin, which increases their proliferation, differentiation to osteoblasts, and the number of mineralized nodules, but inhibits their differentiation to adipocytes. The aim of the present report was to study the direct effect of leptin on control and osteoporotic MSCs analyzing whether the protective effect of leptin against osteoporosis could be expressed by inhibition of adipocyte differentiation. MSCs from control, and osteoporotic donors were subjected to adipogenic conditions, in the absence or in the presence of 62.5 nM leptin. The number of adipocytes, the content of PPARg protein, and mRNA, and leptin mRNA were measured by flow cytometry, Western blot, and RT-PCR, respectively. Results indicate that control and osteoporotic MSCs differ in their adipogenic potential as shown by expression of active PPARg protein. Leptin exerted an antiadipogenic effect only on control MSCs increasing the proportion of inactive phosphorylated PPARg protein. Finally, results obtained during adipogenesis of osteoporotic cells suggest that this process is abnormal not only because of increased adipocyte number, but because of impaired leptin cells response.

- by Pablo Astudillo
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- Cell Differentiation, Cellular, Leptin, Adipogenesis
- by Frédérique Balandras and +1
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- Engineering, Technology, Biotechnology, Cell Division

Peroxisome proliferator-activated receptor (PPAR) α and γ are key regulators of lipid homeostasis and insulin resistance. In this study, we characterize the pharmacological profiles of PAR-5359, a dual agonist of PPARα and γ with well-balanced activities. In transient transactivation assay, PAR-5359 (3-(4-{2[4-(4chlorophenyl)-3,6-dihydro-2H-pyridin-1-yl]-ethoxy}-phenyl)-(2S)-ethoxy-propionic acid) significantly activated human and mouse PPARα and γ without activating PPARδ. In functional assays using human mesenchymal stem cells and human hepatoma HepG2 cells, PAR-5359 significantly induced adipocyte differentiation and human ApoA1 secretion, which coincided with its transactivation potencies against the corresponding human receptor subtypes. Interestingly, PAR-5359 showed equivalent potencies against the mouse receptor subtypes (α and γ; 2.84 μM and 3.02 μM, respectively), which suggests the possibility that PAR-5359 could simultaneously activates each subtype of receptors subtype in under physiological conditions. In an insulinresistant ob/ob mouse model, PAR-5359 significantly reduced plasma insulin levels, improved insulin sensitivity (HOMA-IR), and completely normalized plasma glucose levels. In a severe diabetic db/db mouse model, PAR-5359 dose-dependently reduced the plasma levels of glucose (ED 30 = 0.07 mg/kg). Furthermore, it lowered plasma levels of non HDL-(ED 30 = 0.13 mg/kg) and total cholesterol (ED 30 = 0.03 mg/kg) in high cholesterol diet-fed rats for 4 days treatment. These results suggest that PAR-5359 has the balanced activities for PPARα and PPARγ in vivo as well as in vitro. And its balanced activities may render PAR-5359 as a pharmacological tool in elucidating the complex roles of PPARα/γ dual agonists.

- by 영준 신
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- Obesity, Insulin Resistance, Blood Glucose, Insulin

Umbilical cord blood (UCB) contains a high number of primitive progenitor cells, allowing UCB to be used as a source of hematopoietic progenitors for clinical transplantation. However the rate of UCB CD34 z stem cells graft is low. Mesenchymal stem cells (MSCs) have been implicated in playing an important role in hematopoietic stem cell engraftment.

- by Saeed Soleimani
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- Hematology, Gamma Rays, Stem Cell, Stem Cell Transplantation

Human adipose tissue was shown to be a very attractive source of mesenchymal stromal cells that have a wide scale of potential applications in reconstructive plastic surgery and regenerative medicine. However, these cells were described to have profound effects on biological behaviour of tumour cells. The aim of this study was to analyze the influence of adipose tissue-derived human mesenchymal stromal cells (AT-MSC) on the proliferation of breast cancer cells. We have tested proliferation of three different human breast cancer cell lines under the influence of AT-MSC derived soluble factors as well as in the direct cocultures. These data were supplemented with the expression analysis of cytokines and their cognate receptors on the target cells. We have observed stimulation of proliferation in breast cancer cells MDA-MB-361, T47D and EGFP-MCF7. AT-MSC were found to secrete wide scale of cytokines, chemokines and growth factors, thus we concluded that this pro-proliferative effect was a result of their synergistic action. These data bring out a need to evaluate whether primary breast tumour derived human cells would respond to these type of stimuli in a similar manner in order to exclude any potential clinical risk related to the application of human mesenchymal stromal cells under the context of patient with history of breast cancer malignancy.

- by D. Palencar
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- Cytokines, Adipose tissue, Clinical Sciences, Stromal Cells

We aimed to evaluate the in vitro osteogenic and osteoinductive potentials of BioS-2P and its ability to promote in vivo bone repair. To investigate osteogenic potential, UMR-106 osteoblastic cells were cultured on BioS-2P and Bioglass 45S5 discs in osteogenic medium. The osteoinductive potential was evaluated using mesenchymal stem cells (MSCs) cultured on BioS-2P, Bioglass 45S5 and polystyrene in non-osteogenic medium. Rat bone calvarial defects were implanted with BioS-2P scaffolds alone or seeded with MSCs. UMR-106 proliferation was similar for both materials, while alkaline phosphatase (ALP) activity and mineralization were higher for BioS-2P. Bone sialoprotein (BSP), RUNX2 and osteopontin (OPN) gene expression and BSP, OPN, ALP and RUNX2 protein expression were higher on BioS-2P. For MSCs, ALP activity was higher on Bioglass 45S5 than on BioS-2P and was lower on polystyrene. All genes were highly expressed on bioactive glasses compared to polystyrene. BioS-2P scaffolds promote...

- by Adalberto Rosa
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- Materials Science, Biomedical Engineering, Tissue Engineering, Glass

The stromal vascular fraction (SVF) is a heterogeneous population of stem/stromal cells isolated from perivascular and extracellular matrix (ECM) of adipose tissue complex (ATC). Administration of SVF holds a strong therapeutic potential for regenerative and wound healing medicine applications aimed at functional restoration of tissues damaged by injuries or chronic diseases. SVF is commonly divided into cellular stromal vascular fraction (cSVF) and tissue stromal vascular fraction (tSVF). Cellular SVF is obtained from ATC by collagenase digestion, incubation/isolation, and pellet-ized by centrifugation. Enzymatic disaggregation may alter the relevant biological characteristics of adipose tissue, while providing release of complex, multiattachment of cell-to-cell and cell-to-matrix, effectively eliminating the bioactive ECM and periadventitial attachments. In many countries , the isolation of cellular elements is considered as a "more than minimal" manipulation, and is most often limited to controlled clinical trials and subject to regulatory review. Several alternative , nonenzymatic methods of adipose tissue processing have been developed to obtain via minimal mechanical manipulation an autologous tSVF product intended for delivery, reducing the procedure duration, lowering production costs, decreasing regulatory burden, and shortening the translation into the clinical setting. Ideally, these procedures might allow for the integration of harvesting and processing of adipose tissue for ease of injection, in a single procedure utilizing a nonexpanded cellular product at the point of care, while permitting intraoperative autologous cellular and tissue-based therapies. Here, we review and discuss the options, advantages, and limitations of the major strategies alternative to enzymatic processing currently developed for minimal manipulation of adipose tissue. STEM CELLS TRANSLATIONAL MEDICINE 2019;8:1265–1271

The aim of this study was to evaluate the osteogenic potential and the vascularization of embroidered, tissue engineered, and cell-seeded 3D poly(3)hydroxybutyrate (PHB) scaffolds in nude rats. Collagen I (coll I)- and collagen I/chondroitin sulfate (coll I/CS)-coated PHB scaffolds were seeded with human mesenchymal stem cells (hMSCs). Proliferation and differentiation were characterized by different biochemical assays in vitro. For animal experiments, the cells were cultivated on coll I- or coll I/CS-coated scaffolds and either expanded or osteogenically differentiated. Scaffolds were piled up to create a 3D scaffold pad and implanted subcutaneously into nude rats. In vitro hMSC showed proliferation and differentiation on PHB scaffolds. Alkaline phosphatase (ALP) and calcium increased in the differentiation medium and in the presence of coll I/CS. In vivo blood vessels were found in the scaffold-stack. Histological/immunohistological analyses of explanted scaffolds showed osteogenic markers such as osteopontin, osteonectin, and coll I around the PHB fibers. Coll I/CS-coated scaffolds with expanded hMSC showed higher values of ALP and calcium than the other combinations. Embroidered PHB scaffolds, coated with extracellular matrix components, provided an adequate environment and, therefore, a template for hMSC which could be differentiated in osteogenic direction. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010

- by Barbe Rentsch
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- Engineering, Tissue Engineering, Stem Cells, Calcium

The ability to repair tissue via percutaneous means may allow interventional pain physicians to manage a wide variety of diseases including peripheral joint injuries and osteoarthritis. This review will highlight the developments in cellular medicine that may soon permit interventional pain management physicians to treat a much wider variety of clinical conditions and highlight an interventional case study using these technologies To determine if isolated and expanded human autologous mesenchymal stem cells could effectively regenerate cartilage and meniscal tissue when percutaneously injected into knees. Case Study Private Interventional Pain Management practice. An IRB approved study with a consenting volunteer in which mesenchymal stem cells were isolated and cultured ex-vivo from bone marrow aspiration of the iliac crest. The mesenchymal stem cells were then percutaneously injected into the subject's knee with MRI proven degenerative joint disease. Pre- and post-treatment su...

- by Michael Freeman
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- Pain, Regeneration, Magnetic Resonance Imaging, Adolescent

The clinically known importance of patient sex as a major risk factor for compromised bone healing is poorly reflected in animal models. Consequently, the underlying cellular mechanisms remain elusive. Because mesenchymal stem cells (MSCs) are postulated to regulate tissue regeneration and give rise to essential differentiated cell types, they may contribute to sex-specific differences in bone healing outcomes. Methods: We investigated sex-specific variations in bone healing and associated differences in MSC populations. A 1.5 mm osteotomy gap in the femora of 8 male and 8 female 12-month-old Sprague-Dawley rats was stabilized by an external fixator. Healing was analyzed in terms of biomechanical testing, bridging and callus size over time (radiography at 2, 4, and 6 weeks after surgery), and callus volume and geometry by μCT at final follow-up. MSCs were obtained from bone marrow samples of an age-matched group of 12 animals (6 per gender) and analyzed for numbers of colony-forming units (CFUs) and their capacity to differentiate and proliferate. The proportion of senescent cells was determined by β-galactosidase staining. Results: Sex-specific differences were indicated by a compromised mechanical competence of the callus in females compared with males (maximum torque at failure, p = 0.028). Throughout the follow-up, the crosssectional area of callus relative to bone was reduced in females (p ≤ 0.01), and the bridging of callus was delayed (p 2weeks = 0.041). μCT revealed a reduced callus size (p = 0.003), mineralization (p = 0.003) and polar moment of inertia (p = 0.003) in female animals. The female bone marrow contained significantly fewer MSCs, represented by low CFU numbers in both femora and tibiae (p femur = 0.017, p tibia = 0.010). Functional characteristics of male and female MSCs were similar. Conclusion: Biomechanically compromised and radiographically delayed bone formation were distinctive in female rats. These differences were concomitant with a reduced number of MSCs, which may be causative for the suboptimal bone healing.

- by Cameron J Wilson
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- Engineering, Wound Healing, Bone Healing, Morphology

Background aims. Bone marrow (BM) mesenchymal stromal cells (MSC) have been identifi ed as a source of pluripotent stem cells used in clinical practice to regenerate damaged tissues. BM MSC are commonly isolated from BM by densitygradient centrifugation. This process is an open system that increases the risk of sample contamination. It is also time consuming and requires technical expertise that may result in variability regarding cellular recovery. The BD Vacutainer ® Cell Preparation Tube ™ (CPT) was conceived to separate mononuclear cells from peripheral blood. The main goal of this study was to verify whether MSC could be isolated from BM using the CPT. Methods. BM was harvested, divided into two equal aliquots and processed using either CPT or a Ficoll-Paque ™ PREMIUM density gradient. Both methods were compared regarding cell recovery, viability, proliferation, differentiation capacities and the presence of MSC progenitors. Results. Similar numbers of mononuclear cells were isolated from BM when comparing the two methods under study. No differences were found in terms of phenotypic characterization, viability, kinetics and lineage differentiation potential of MSC derived by CPT or Ficoll. Surprisingly, a fi broblast -colony-forming unit (CFU-F) assay indicated that, with CPT, the number of MSC progenitors was 1.8 times higher compared with the Ficoll gradient separation. Conclusions. The CPT method is able to isolate MSC effi ciently from BM, allowing the enrichment of MSC precursors.

- by Daniel Remondini
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- Kinetics, Adolescent, Cell separation, Child

An ideal scaffold that provides a combination of suitable mechanical properties along with biological signals is required for successful ligament/tendon regeneration in mesenchymal stem cell-based tissue engineering strategies. Among the various fibre-based scaffolds that have been used, hybrid fibrous scaffolds comprising both microfibres and nanofibres have been recently shown to be particularly promising. This study developed a biohybrid fibrous scaffold system by coating bioactive bFGF-releasing ultrafine PLGA fibres over mechanically robust slowly-degrading degummed knitted microfibrous silk scaffolds. On the ECM-like biomimetic architecture of ultrafine fibres, sustained release of bFGF mimicked the ECM in function, initially stimulating mesenchymal progenitor cell (MPC) proliferation, and subsequently, their tenogeneic differentiation. The biohybrid scaffold system not only facilitated MPC attachment and promoted cell proliferation, with cells growing both on ultrafine PLGA fibres and silk microfibres, but also stimulated tenogeneic differentiation of seeded MPCs. Upregulated gene expression of ligament/tendon-specific ECM proteins and increased collagen production likely contributed to enhancing mechanical properties of the constructs, generating a ligament/tendon analogue that has the potential to be used to repair injured ligaments/tendons.

- by Sambit Sahoo
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- Materials Science, Biomaterials, Electrospinning, Medicine

Cell-based therapies have the potential to treat a diversity of disease conditions, many representing significant and long-standing unmet medical needs. Certain properties of cell-based therapies, such as differentiation potential and proliferative potential, present safety concerns uniquely distinct from those of small molecule drugs and other macromolecule biologics. These cellular products carry risks associated with localized host tissue response, long-term persistence, ectopic tissue formation, differentiation to undesirable cell and tissue types, uncontrollable biodistribution, tumorigenicity, and immunogenicity. Such risks are generally evaluated in preclinical animal model studies as part of a comprehensive safety program prior to administration in humans. However, safety assessment for these products can be challenging because of inconsistent approaches to product characterization, inadequately defined product parameters that anticipate adverse events, and the lack of stand...

- by Mahendra Rao
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- Tissue Engineering, Regenerative Medicine, Medicine, Safety

Mesenchymal stem cells (MSCs) are now known to display not only stem cell multipotency, but also robust antiinfl ammatory and regenerative properties. After widespread in-vitro and in-vivo preclinical testing, autologous and allogeneic MSCs have been applied in a range of immune mediated conditions, including graft versus host disease, Crohn´s disease, multiple sclerosis, refractory systemic lupus erythematosus and systemic sclerosis. Current data suggests that MSCs may not only replace diseased tissues, but also exert several trophic, regenerative and antiinfl ammatory eff ects. While the clinical outcome in case reports and phase I-II trials seems occasionally striking, these limited results point to the need to perform controlled multicenter trials. Future advances from stem cell science can be expected to pinpoint signifi cant MSC subpopulations and/or stem cell markers for improved regenerative or immunoregulatory properties.

- by Saudia Villanueva
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- Medicine, Biological Sciences, Autoimmune diseases, Biological

Around 5 million annual births in EU and 131 million worldwide give a unique opportunity to collect lifesaving Wharton's jelly derived mesenchymal stem cells (WJ-MSC). Evidences that these cells possess therapeutic properties are constantly accumulating. Collection of WJ-MSC is done at the time of delivery and it is easy and devoid of side effects associated with collection of adult stem cells from bone marrow or adipose tissue. Likewise, their rate of proliferation, immune privileged status, lack of ethical concerns, nontumorigenic properties make them ideal for both autologous and allogeneic use in regenerative medicine applications. This review provides an outline of the recent findings related to WJ-MSC therapeutic effects and possible advantage they possess over MSC from other sources. Results of first clinical trials conducted to treat immune disorders are highlighted.

- by Ilona Kalaszczynska
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- Technology, Adult Stem Cells, Regenerative Medicine, Biological Sciences

We have examined the effect of retinoic acid (RA) on differentiation of bone marrow-derived CD15 þ , Oct4 þ and CXCR4 þ cells into male germ cells. Bone marrow stem cells (BMSCs) were isolated from the femur of 3-4-week-old male C57BL/6 mice. Magnetic-activated cell sorting (MACS) system was used to sort CD15 þ , Oct4 þ and CXCR4 þ cells. RT-PCR was used to follow the expression of pluripotency markers. Sorted CD15 þ , Oct4 þ and CXCR4 þ cells were cultured in an undifferentiated condition on a feeder layer of mitomycin C-inactivated C2C12. The embryoid-like bodies were differentiated into male germ cells by retinoic acid. To identify the expression of male germ specific markers, differentiated cells were analysed by means of reverse transcriptase polymerase chain reaction (RT-PCR) and immunofluorescence staining. RT-PCR and immunofluorescence show that bone marrow-derived CD15 þ , Oct4 þ and CXCR4 þ cells express pluripotency markers, Oct4, Nanog, Rex-1, SOX-2 and AP. The purified CD15 þ , Oct4 þ and CXCR4 þ formed structures like embryoid bodies when plated over a feeder layer; these bodies were alkaline phosphatase positive. When cells were induced by RA, bone marrow-derived CD15 þ , Oct4 þ and CXCR4 þ were positive for Mvh, Dazl, Piwil2, Dppa3 and Stra8, that known molecular markers of male germ cells. Thus RA can induce differentiation of mouse bone marrow-derived CD15 þ , Oct4 þ and CXCR4 þ cells into male germ cells in vitro. Negative results for the gene expression analysis of female germ cells markers, GDF9 and ZP3, confirmed this conclusion.

- by iraj ragerdi
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- Cell Biology, Transcription Factors, Cell Differentiation, Mice

Intracanal disinfection is a crucial step in regenerative endodontic procedures. However, this novel endodontic treatment lacks standardization, and numerous treatment protocols have been reported without knowledge of the effect of disinfection protocols on the survival of stem cells. The aim of this study was to test the hypothesis that different root canal irrigation protocols alter survival of stem cells from the apical papilla (SCAP).

- by Nicholas Dybdal-Hargreaves and +1
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- Dentistry, Regeneration, Cell Adhesion, Confocal Microscopy

Mesenchymal stem cells (MSC) are multipotent cells that differentiate into osteoblasts, myocytes, chondrocytes and adipocytes as well as insulin-producing cells. The mechanism underlying their in vivo differentiation is not clear and is thought to be caused by spontaneous cell fusion or factors present in the microenvironment. However, their ease of isolation, high 'ex-vivo' expansion potential and ability to differentiate into multiple lineages make them attractive tools for potential use in cell therapy. MSC have been isolated from several tissues, including bone/bone marrow, fat, Wharton's jelly, umbilical cord blood, placenta and pancreas. The 'immunosuppressive' property of human MSC makes them an important candidate for cellular therapy in allogeneic settings. Use of allogeneic MSC for repair of large defects may be an alternative to autologous and allogeneic tissue-grafting procedures. An allogeneic approach would enable MSC to be isolated from any donor, expanded and cryopreserved, providing a readily available source of progenitors for cell replacement therapy.

- by Jyoti Kode
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- Tissue Engineering, Regeneration, Tissue Regeneration, Cell therapy

Putative stem cells have been isolated from various tissue fluids such as synovial fluid, amniotic fluid, menstrual blood, etc. Recently the presence of nestin positive putative mammary stem cells has been reported in human breast milk. However, it is not clear whether they demonstrate multipotent nature. Since human breast milk is a non-invasive source of mammary stem cells, we were interested in examining the nature of these stem cells. In this pursuit, we could succeed in isolating and expanding a mesenchymal stem cell-like population from human breast milk. These cultured cells were examined by immunofluorescent labeling and found positive for mesenchymal stem cell surface markers CD44, CD29, SCA-1 and negative for CD33, CD34, CD45, CD73 confirming their identity as mesenchymal stem cells. Cytoskeletal protein marker analysis revealed that these cells expressed mesenchymal stem cells markers, namely, nestin, vimentin, smooth muscle actin and also manifests presence of E-Cadherin, an epithelial to mesenchymal transition marker in their early passages. Further we tested the multipotent differentiation potential of these cells and found that they can differentiate into adipogenic, chondrogenic and oesteogenic lineage under the influence of specific differentiation cocktails. This means that these mesenchymal stem cells isolated from human breast milk could potentially be "reprogrammed" to form many types of human tissues. The presence of multipotent stem cells in human milk suggests that breast milk could be an alternative source of stem cells for autologous stem cell therapy although the significance of these cells needs to be determined.

- by Ramesh R Bhonde
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- Fluorescence Microscopy, Stem Cell, Stem cell Therapy, Cell Differentiation

Poor angiogenesis within tissue-engineered grafts has been identified as a main challenge limiting the clinical introduction of bone tissue-engineering (BTE) approaches for the repair of large bone defects. Thick BTE grafts often exhibit poor cellular viability particularly at the core, leading to graft failure and lack of integration with host tissues. Various BTE approaches have been explored for improving vascularisation in tissue-engineered constructs and are briefly discussed in this review. Recent investigations relating to co-culture systems of endothelial and osteoblast-like cells have shown evidence of BTE efficacy in increasing vascularization in thick constructs. This review provides an overview of key concepts related to bone formation and then focuses on the current state of engineered vascularized co-culture systems using bone repair as a model. It will also address key questions regarding the generation of clinically relevant vascularized bone constructs as well as potential directions and considerations for research with the objective of pursuing engineered co-culture systems in other disciplines of vascularized regenerative medicine. The final objective is to generate serious and functional long-lasting vessels for sustainable angiogenesis that will enable enhanced cellular survival within thick voluminous bone grafts, thereby aiding in bone formation and remodelling in the long term. However, more evidence about the quality of blood vessels formed and its associated functional improvement in bone formation as well as a mechanistic understanding of their interactions are necessary for designing better therapeutic strategies for translation to clinical settings. Figure 1. (A) Hierarchical structure of bone from a sub-nanostructure of collagen molecules to a nanostructure of cylindrically arranged microfibrils to lamellar layers forming the macrostructure of cortical bone (adapted from Rho et al. (1998). (B) Vascularised bone anatomy and microenvironmental influences such as biomechanical, microarchitectural and low oxygen tension factors Y. Liu et al.

- by Jerry Chan
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- Biomedical Engineering, Tissue Engineering, Hypoxia, Regenerative Medicine

The surface charge of a biomaterial represents a promising tool to direct cellular behavior, which is crucial for therapeutic approaches in regenerative medicine. To expand the understanding of how the material surface charge affects protein adsorption and mesenchymal stem cell behavior, differently charged surfaces with zeta potentials spanning from -25 mV to +15 mV were fabricated by the conjugation of poly(amidoamine) to alginate-based hydrogels. We showed that the increase of the biomaterials surface charge resulted in enhanced quantities of biologically available, surface-attached proteins. Since different surface charges were equalized after protein adsorption, mesenchymal stem cells interacted rather with diverse protein compositions instead of different surface features. Besides an enhanced cell attachment to increasingly positively charged surfaces, the cell spreading area and the expression of adhesion-related genes integrin α5 and tensin 1 were found to be increased after...

Early and effective integration of a metal implant into bone tissue is of crucial importance for its long-term stability. While different material properties including surface roughness and wettability but also initial blood-implant surface interaction are known to influence this osseointegration, implications of the latter process are still poorly understood. In this study, early interaction between blood and the implant surface and how this affects the mechanism of osseointegration were investigated. For this, blood coagulation on a micro-roughened hydrophobic titanium (Ti) surface (SLA-Hphob) and on a hydrophilic micro-roughened Ti surface with nanostructures (SLActive-HphilNS), as well as the effects of whole human blood pre-incubation of these two surfaces on the differentiation potential of primary human bone cells (HBC) was assessed. Interestingly, pre-incubation with blood resulted in a dense fibrin network over the entire surface on SLActive-HphilNS but only in single patch...

- by Markus Rottmar
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- Titanium, Multidisciplinary, Adsorption, Cell Differentiation

The treatment of Interstinal Cystitisis (IC) is still challenge for urologist. Available therapies do not result in long-term control of symptoms and do not provide pain relive to patients. Unique abilities of mesenchymal stem cells (MSC) could be used to develop new treatment approaches for Interstitial Cystitis. Conditioned Medium (CM) derived from MSC culture is rich in plenty of growth factors, cytokines and trophic agents which were widely reported to enhance regeneration of urinary bladder in different conditions. This ready mixture of growth factors could be used to develop intravesical therapy for patients with IC. MSC-CM has anti-apoptotic, anti-inflammatory, supportive, angiogenic, immunosuppressive and immunomodulative properties and seems to be ideal substance to prevent IC recurrence and to create favorable environment for regeneration of damaged bladder wall.

- by Tomasz Drewa
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- Mesenchymal Stromal Cells

Polyoxymethylene (POM, acetal homopolymer, polyacetal), commercialized as Delrin by DuPont, is an engineering resin with mechanical properties that make it useful for the prototyping and manufacture of laboratory apparatus. These properties include excellent, "metal-like," machining characteristics and dimensional stability, as well as thermal stability,

- by Luis Solchaga
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- Engineering, Tissue Engineering, Stem Cells, Immunohistochemistry

We have prepared multiwalled carbon nanotube (MWCNT)/In 2 O 3 composites using a simple impregnation method. The precursor compound indium(III) chloride (InCl 3 ) was used to cover the surface of MWCNTs and distilled water was used as solvent. The applied mass ratio was 4:1 (In 2 O 3 /MWCNT), and during the calcination process different temperatures (300, 350 and 400°C) were investigated. The produced materials were characterized by Xray diffraction, energy-dispersive X-ray spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, transmission and scanning electron microscopy, and a thermogravimetric analysis was executed also. The average thickness of the produced surface layer and the average sizes of the In 2 O 3 particles were calculated with the Scherrer formula and the ImageJ-program. The results show that the heat treatment temperature affected the characteristic morphology and the crystal structure of the as-prepared composite.

- by Péter Berki and +3
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- Engineering, Materials Engineering, Chemical Engineering, Condensed Matter Physics
- by Jérome Allain
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- Engineering, Treatment Outcome, Biological Sciences, Mesenchymal stem cells
- by Theofanis Chatzistamatiou and +2
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- Immunology, Cell separation, Allografts, Clinical Sciences

The STRO-1 antibody can be used as a single reagent to isolate human bone marrow stromal stem cells (BMSSC), owing to its restricted specificity to a cell surface molecule expressed by clonogenic BMSSC, with little or no reactivity to hematopoietic stem/progenitor populations or mature stromal elements. The present protocol uses a combination of two different immunoselection methodologies in an attempt to generate highly purified preparations of BMSSC. This process involves the initial isolation of a minor subpopulation of bone marrow mononuclear cells (approx 10%) expressing the STRO-1 antigen, by means of magnetic activated cell sorting. Dual-color fluorescence activated cell sorting is then used as a secondary step to further purify the rare STRO-1bright expressing fraction that contains all of the colony-forming BMSSC, based on their co-expression of a secondary cell surface marker, CD106 (VCAM-1).

This review focuses on the therapeutic potential of stem cells harvested from the Wharton's Jelly of the human umbilical cord. Recently, investigators have found that a potent stem cell population exists within the Wharton's Jelly. In this review, the authors define a new subset of stem cells, termed perinatal stem cells, and compare them to other sources of stem cells. Furthermore, cryopreservation of Wharton's Jelly stem cells is described for potential use in future cell based therapies and/or regenerative medicine applications. Current evidence of the application of mesenchymal stem cells from various sources in both pre-clinical and clinical trials is reviewed in the context of potential indications of use for Wharton's Jelly derived mesenchymal stem cells.

- by Kyle Cetrulo and +1
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- Stem Cells, Stem Cell, Regenerative Medicine, Stem Cell Transplantation
- by Frank Marini
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- Clinical Sciences, Stromal Cells, Mesenchymal Stromal Cells

Tissue engineering scaffolds are designed to influence the physical, chemical and biological environment surrounding a cell population. In this review we focus on our own work and introduce a range of strategies and materials used for tissue engineering, including the sources of cells suitable for tissue engineering: embryonic stem cells, bone marrow-derived mesenchymal stem cells and cord-derived mesenchymal stem cells. Furthermore, we emphasize the developments in custom scaffold design and manufacture, highlighting laser sintering, supercritical carbon dioxide processing, growth factor incorporation and zoning, plasma modification of scaffold surfaces, and novel multi-use temperature-sensitive injectable materials.

- by Kevin M Shakesheff
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- Biomedical Engineering, Tissue Engineering, Stem Cells, Surface Engineering

Severe spinal cord injury (SCI) often causes temporary or permanent damages in strength, sensation or autonomic functions below the site of the injury. So far there is still no effective treatment for SCI. Mesenchymal stem cells (MSCs) have been used to repair injured spinal cord as an effective strategy. However, the low neural differentiation frequency of MSCs has limited its application. The present study attempted to explore whether the grafted MSC-derived neural-like cells in a gelatin sponge (GS) scaffold could maintain neural features or transdifferentiate into myelin-forming cells in the spinal cord transected. We constructed an engineered tissue by co-seeding of MSCs with genetically enhanced expression of neurotrophin-3 (NT-3) and its high affinity receptor tropomyosin receptor kinase C (TrkC), respectively, into a 3-dimensional GS scaffold to promote the MSCs differentiating into neural-like cells, and transplanted it into the gap of rat spinal cord transected completely....

- by Xiang Zeng
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- Technology, Animal Behavior, Regeneration, Stem cell Therapy

Advances in Biochemical Engineering/Biotechnology reviews actual trends in modern biotechnology.

- by Birgit Weyand
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- Tissue Engineering, Stem Cell, Regenerative Medicine, Cell separation

Osterix (Osx) is a transcription factor required for the differentiation of preosteoblasts into fully functioning osteoblasts. However, the pattern of Osx activation during preosteoblast differentiation and maturation has not been clearly defined. Our aim was to study Osx activation during these processes in osteoblasts differentiating from murine and human embryonic stem cells (ESC). To do this, we constructed an Osx-GFP fusion protein reporter system to track Osx translocation within the cells. The distribution of Osx-GFP at representative stages of differentiation was also investigated by screening primary osteoblasts, mesenchymal stem cells, synoviocytes, and pre-adipocytes. Our experiments revealed that Osx-GFP protein was detectable in the cytoplasm of cultured, differentiated ESC 4 days after plating of enzymatically dispersed embryoid bodies. Osterix-GFP protein became translocated into the nucleus on day 7 following transfer of differentiated ESC to osteogenic medium. After 14 days of differentiation, cells showing nuclear translocation of Osx-GFP formed rudimentary bone nodules that continued to increase in number over the following weeks (through day 21). We also found that Osx translocated into the nuclei of mesenchymal stem cells (C3H10T1/2) and pre-osteoblasts (MC3T3-E1) and showed partial activation in pre-adipocytes (MC3T3-L1). These data suggest that Osx activation occurs at a very early point in the differentiation of the mesenchymal-osteoblastic lineage.

- by Pascale Louis-plence and +1
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- Immunology, Collagen, Mice, Mesenchymal Stem Cell
- by Marina Boido and +1
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- Cognitive Science, Amyotrophic Lateral Sclerosis, Neurosciences, Mesenchymal Stromal Cells

Restoration of articular cartilage function and structure following pathological or traumatic damage is still considered a challenging problem in the orthopaedic field. Currently, tissue engineering-based reconstruction of articular cartilage is a feasible and continuously developing strategy to restore structure and function. Successful articular cartilage tissue engineering strategy relies largely on several essential components including cellular component, supporting 3D carrier scaffolding matrix, bioactive agents, proper physical stimulants, and safe gene delivery. Designing the right formulations from these components remain the main concern of the orthopaedic community. Utilization of mesenchymal stem cells (MSCs) for articular cartilage tissue engineering is continuously increasing compared to use of chondrocytes. Various sources of MSCs have been investigated including adipose tissue, amniotic fluid, blood, bone marrow, dermis, embryonic stem cells, infrapatellar fat pad, m...

- by Tamer Ahmed
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- Tissue Engineering, Cytokines, Bone Morphogenetic Proteins, Clinical Sciences