MSCs conditioned media and umbilical cord blood plasma metabolomics and composition

Hybrid scaffolds for bone tissue engineering: Integration of composites and bioactive hydrogels loaded with hDPSCs

Bone tissue regeneration remains a significant challenge in clinical settings due to the complexity of replicating the mechanical and biological properties of bone environment. This study addresses this challenge by proposing a hybrid scaffold designed to enhance both bioactivity and physical stability for bone tissue regeneration. This research is the fisrt to develop a rigid 3D structure composed of polycaprolactone (PCL) and hydroxyapatite nanoparticles (nHA) integrated with a bioink containing human dental pulp stem/stromal cells (hDPSCs), alginate, nHA and collagen (Col). The biofabricated constructs were extensively characterized through cytocompatibility tests, osteogenic differentiation assessment, and biocompatibility evaluation in a rat model. In vitro results demontrated that the hybrid scaffolds presented significantly higher cell viability after 168 h compared to the control group. Furthermore, the hybrid scaffolds showed increased osteogenic differentiation relative to other groups. In vivo evaluation indicated good biocompatibility, characterized by minimal inflammatory response and successful tissue integration. These findings highlight the scaffold's potential to support bone tissue regeneration by combining the mechanical strength of PCL and nHA with the biological activity of the alginate-nHA-Col and hDPSCs bioink. The current study provides a promising foundation for the development of biomaterials aimed at improving clinical outcomes in bone repair and regeneration, particulary for the treatment of critical-size bone defects, targeted drug administration, and three-dimensional models for bone tissue engineering.

Allogeneic Umbilical Cord Plasma Eyedrops for the Treatment of Recalcitrant Dry Eye Disease Patients

BACKGROUND

Dry eye disease is a significant disease in Singapore. While there have been studies using allogenic cord serum for the treatment of dry eye disease, treatment of dry eyes with allogenic umbilical cord plasma drops has yet to be started in Singapore.

PURPOSE

To evaluate the effectiveness of umbilical cord plasma eyedrops for the treatment of recalcitrant dry eyes in a local Singaporean context.

METHODS

This is an observational, longitudinal, interventional study for dry eye patients who did not show clear improvement after standard therapy. Patients were recruited from 2020 to 2023 from the dry eye clinic of the Singapore National Eye Center. Umbilical cord plasma was delivered frozen to patients and stored in home freezers. All participants underwent a standardized clinical evaluation for dry eye, and data were collected.

RESULTS

There were 40 participants (7 males and 33 females). The duration of follow-up was 5.52 ± 1.57 months. Kerato-epitheliopathy staining score, TBUT (tear breakup time), and SPEED (Standard Patient Evaluation of Eye Dryness Questionnaire) scores significantly improved after treatment. No statistically significant improvement was found in terms of visual acuity, according to Schirmer's score.

CONCLUSION

Cord plasma eye drops significantly improved kerato-epitheliopathy staining scores in recalcitrant dry eye patients. Allogeneic plasma is a promising form of treatment for recalcitrant dry eye.

Cell Therapy for Androgenetic Alopecia: Elixir or Trick?

Androgenetic alopecia is the most common cause of hair loss aggravated by increased life pressure, tension, and anxiety. Although androgenetic alopecia (AGA) does not significantly effect physical health, it can have serious negative impact on the mental health and quality of life of the patient. Currently, the effect of medical treatment for AGA is not idealistic, stem cell-based regenerative medicine has shown potential for hair regrowth and follicle repair, but the long-term effect and mechanism of stem cell therapy is not quite explicit. In this review, we summarize the methods, efficacy, mechanism, and clinical progress of stem cell therapies for AGA by now, hope it will present a more comprehensive view in this topic.

Thymoquinone-treated mouse mesenchymal stem cells-derived conditioned medium inhibits human breast cancer cells in vitro

Breast cancer is now the most prevalent cancer in females, therefore, it is essential to identify factors affecting its initiation and progression. Mesenchymal stem cells (MSCs) have received considerable attention in stem cell-based therapies and drug delivery applications. Because the therapeutic potential of MSCs is primarily achieved by their paracrine effects, thus identifying and employing bioactive molecules that promote the paracrine activity of MSCs is crucial for their efficient use in cancer treatment. Thymoquinone (TQ) has many biomedical properties, including anti-inflammatory, anti-diabetic, anti-aging, anti-cancer, etc. In addition, it has been found that TQ affects the self-renewal and immunomodulatory properties of MSCs. The present study aimed to investigate the effect of TQ-treated mouse bone marrow-derived MSCs conditioned medium (TQ-MSC-CM) on the biological characteristics of breast cancer cell line MCF7. MSCs were cultured and treated with TQ for 24 h. The TQ-MSC-CM and MSC-CM were collected, and their effects were investigated on ROS production, mitochondrial membrane potential (MMP), cell death, cell cycle, and migration of MCF7 cells by DCFDA-cellular ROS assay, Rhodamine-123 MMP assay, Annexin-PI staining and Caspase-3/7 activity assays, PI-staining and flow-cytometry, and in vitro wound healing assay, respectively. Moreover, the effects of TQ-MSC-CM and MSC-CM were studied on Cdk4, Sox2, c-Met, and Bcl2 gene expression by real-time PCR. Results demonstrated that MSC-CM and TQ-MSC-CM did not have a significant effect on the apoptosis induction in MCF7 cells; however, they significantly stimulated necrosis in the cells. Although TQ-MSC-CM promoted ROS production in MCF7 cells, it decreased the MMP of the cells. TQ-MSC-CM also induced Bcl2 anti-apoptosis gene expression and Casp-3/7 activity in cells. In addition, although MSC-CM induced MCF7 cells to enter the cell cycle, TQ-MSC-CM inhibited its progression. TQ-MSC-CM also downregulated the Cdk4 and Sox2 gene expression. Furthermore, TQ-MSC-CM induced the migration potential of MCF7 in a c-Met-independent manner. Altogether, we conclude that TQ may induce programmed necrosis and inhibits the proliferation and migration of the breast cancer cells by affecting the paracrine activity of MSCs.

Neuroprotective Effect of Wharton's Jelly-Derived Mesenchymal Stem Cell-Conditioned Medium (WJMSC-CM) on Diabetes-Associated Cognitive Impairment by Improving Oxidative Stress, Neuroinflammation, and Apoptosis

According to strong evidence, diabetes mellitus increases the risk of cognitive impairment. Mesenchymal stem cells have been shown to be potential therapeutic agents for neurological disorders. In the current study, we aimed to examine the effects of Wharton's jelly-derived mesenchymal stem cell-conditioned medium (WJMSC-CM) on learning and memory, oxidative stress, apoptosis, and histological changes in the hippocampus of diabetic rats. Randomly, 35 male Sprague Dawley rats weighing 260-300 g were allocated into five groups: control, diabetes, and three diabetic groups treated with insulin, WJMSC-CM, and DMEM. The injections of insulin (3 U/day, S.C.) and WJMSC-CM (10 mg/week, I.P.) were done for 60 days. The Morris water maze and open field were used to measure cognition and anxiety-like behaviors. Colorimetric assays were used to determine hippocampus glutathione (GSH), malondialdehyde (MDA) levels, and antioxidant enzyme activity. The histopathological evaluation of the hippocampus was performed by Nissl staining. The expression levels of Bax, Bcl-2, BDNF, and TNF-α were detected by real-time polymerase chain reaction (RT-PCR). According to our findings, WJMSC-CM significantly reduced and increased blood glucose and insulin levels, respectively. Enhanced cognition and improved anxiety-like behavior were also found in WJMSC-CM-treated diabetic rats. In addition, WJMSC-CM treatment reduced oxidative stress by lowering MDA and elevating GSH and antioxidant enzyme activity. Reduced TNF-α and enhanced Bcl-2 gene expression levels and elevated neuronal and nonneuronal (astrocytes and oligodendrocytes) cells were detected in the hippocampus of WJMSC-CM-treated diabetic rats. In conclusion, WJMSC-CM alleviated diabetes-related cognitive impairment by reducing oxidative stress, neuroinflammation, and apoptosis in diabetic rats.

The dark side of foetal bovine serum in extracellular vesicle studies

Extracellular vesicles (EVs) have been shown to be involved in cell-cell communication and to take part in both physiological and pathological processes. Thanks to their exclusive cargo, which includes proteins, lipids, and nucleic acids from the originating cells, they are gaining interest as potential biomarkers of disease. In recent years, their appealing features have been fascinating researchers from all over the world, thus increasing the number of in vitro studies focused on EV release, content, and biological activities. Cultured cell lines are the most-used source of EVs; however, the EVs released in cell cultures are influenced by the cell culture conditions, such as the use of foetal bovine serum (FBS). FBS is the most common supplement for cell culture media, but it is also a source of contaminants, such as exogenous bovine EVs, RNA, and protein aggregates, that can contaminate the cell-derived EVs and influence their cargo composition. The presence of FBS contaminants in cell-derived EV samples is a well-known issue that limits the clinical applications of EVs, thus increasing the need for standardization. In this review, we will discuss the pros and cons of using FBS in cell cultures as a source of EVs, as well as the protocols used to remove contaminants from FBS.

PSME4 Degrades Acetylated YAP1 in the Nucleus of Mesenchymal Stem Cells

Intensive research has focused on minimizing the infarct area and stimulating endogenous regeneration after myocardial infarction. Our group previously elucidated that apicidin, a histone deacetylase (HDAC) inhibitor, robustly accelerates the cardiac commitment of naïve mesenchymal stem cells (MSCs) through acute loss of YAP1. Here, we propose the novel regulation of YAP1 in MSCs. We found that acute loss of YAP1 after apicidin treatment resulted in the mixed effects of transcriptional arrest and proteasomal degradation. Subcellular fractionation revealed that YAP1 was primarily localized in the cytoplasm. YAP1 was acutely relocalized into the nucleus and underwent proteasomal degradation. Interestingly, phosphor-S127 YAP1 was shuttled into the nucleus, suggesting that a mechanism other than phosphorylation governed the subcellular localization of YAP1. Apicidin successfully induced acetylation and subsequent dissociation of YAP1 from 14-3-3, an essential molecule for cytoplasmic restriction. HDAC6 regulated both acetylation and subcellular localization of YAP1. An acetylation-dead mutant of YAP1 retarded nuclear redistribution upon apicidin treatment. We failed to acquire convincing evidence for polyubiquitination-dependent degradation of YAP1, suggesting that a polyubiquitination-independent regulator determined YAP1 fate. Nuclear PSME4, a subunit of the 26 S proteasome, recognized and degraded acetyl YAP1 in the nucleus. MSCs from PSME4-null mice were injected into infarcted heart, and aberrant sudden death was observed. Injection of immortalized human MSCs after knocking down PSME4 failed to improve either cardiac function or the fibrotic scar area. Our data suggest that acetylation-dependent proteasome subunit PSME4 clears acetyl-YAP1 in response to apicidin treatment in the nucleus of MSCs.

Equilibrium among Inflammatory Factors Determines Human MSC-Mediated Immunosuppressive Effect

Mesenchymal stem cells (MSCs) are thought to be a promising therapeutic agent due to their multiple paracrine and immunomodulatory properties, providing protection from chronic inflammation and promoting tissue repair. MSCs can regulate the balance of pro-inflammatory and anti-inflammatory factors in inflamed tissues, creating a microenvironment necessary for successful healing; however, their interactions with immune cells are still poorly studied. We examined the temporal and spatial changes in gene regulation and the paracrine milieu accompanying the MSC-mediated immunosuppression effect in mixed cultures with activated peripheral blood mononuclear cells (PBMCs). Our data reveal that the peak of suppression of PBMC proliferation was achieved within 48 h following co-culture with MSCs and subsequently did not undergo a significant change. This effect was accompanied by an increase in COX-2 expression and an induction of IDO synthesis in MSCs. At this point, the expression of IL-1, IL-6, IL-8, IFN-γ, MCP-1, and G-CSF was upregulated in co-cultured cells. On the contrary, we observed a decrease in the concentrations of IL-10, IL-13, IL-5, and MIP-1b in co-culture supernatants compared to intact cultures of activated PBMCs. The regulation of IDO, IL-1, IL-6, and G-CSF production was accomplished with the involvement of direct cell-cell contact between MSCs and PBMCs. These findings provide new insights into the use of potential precondition inducers or their combinations to obtain functionally qualified MSCs for more effective treatment of inflammatory diseases.

Secretomes as an emerging class of bioactive ingredients for enhanced cosmeceutical applications

Skin aging is predominantly caused by either intrinsic or extrinsic factors, leading to undesirable skin features. Advancements in both molecular and cellular fields have created possibilities in developing novel stem cell-derived active ingredients for cosmeceutical applications and the beauty industry. Mesenchymal stromal cell (MSC)-derived secretomes or conditioned media hold great promise for advancing skin repair and regeneration due to the presence of varying cytokines. These cytokines signal our cells and trigger biological mechanisms associated with anti-inflammatory, antioxidant, anti-aging, proliferative, and immunomodulatory effects. In this review, we discuss the potential of MSC secretomes as novel biomaterials for skincare and rejuvenation by illustrating their mechanism of action related to wound healing, anti-aging, and whitening properties. The advantages and disadvantages of secretomes are compared to both plant-based and animal-derived extracts. In addition, this paper reviews the current safety standards, regulations, market products and research work related to the cosmeceutical applications of secretomes along with strategies to maintain and improve the therapeutic efficacy and production of secretomes. The future outlook of beauty industry is also presented. Lastly, we highlight significant challenges to be addressed for the clinical realization of MSC secretomes-based skin therapies as well as providing perspectives for the future direction of secretomes.

Umbilical cord blood plasma-derived exosomes as a novel therapy to reverse liver fibrosis

Background

Cirrhosis is a chronic liver disease whereby scar tissue replaces healthy liver parenchyma, leading to disruption of the liver architecture and hepatic dysfunction. Currently, there is no effective disease-modifying therapy for liver fibrosis. Recently, our group demonstrated that human umbilical cord blood (UCB) plasma possesses therapeutic effects in a rat model of acute liver failure.

Methods

In the current study, we tested whether exosomes (Exo) existed in UCB plasma and if they produced any antifibrotic benefits in a liver fibrosis model.

Results

Our results showed that UCB-Exo improved liver function and increased matrix metalloproteinase/tissue inhibitor of metalloproteinase degradation to reduce the degree of fibrosis. Moreover, UCB-Exo were found to suppress hepatic stellate cell (HSC) activity in vitro. These effects were associated with suppression of transforming growth factor-β/inhibitor of DNA binding 1 signaling.

Conclusions

These results further support that UCB-Exo have antifibrotic effects in mice with liver fibrosis and activated HSCs and may herald a new cell-free antifibrotic therapy.

Metabolomic Applications in Stem Cell Research: a Review

This review describes the use of metabolomics to study stem cell (SC) characteristics and function, excluding SCs in cancer research, suited to a fully dedicated text. The interest in employing metabolomics in SC research has consistently grown and emphasis is, here, given to developments reported in the past five years. This text informs on the existing methodologies and their complementarity regarding the information provided, comprising untargeted/targeted approaches, which couple mass spectrometry or nuclear magnetic resonance spectroscopy with multivariate analysis (and, in some cases, pathway analysis and integration with other omics), and more specific analytical approaches, namely isotope tracing to highlight particular metabolic pathways, or in tandem microscopic strategies to pinpoint characteristics within a single cell. The bulk of this review covers the existing applications in various aspects of mesenchymal SC behavior, followed by pluripotent and neural SCs, with a few reports addressing other SC types. Some of the central ideas investigated comprise the metabolic/biological impacts of different tissue/donor sources and differentiation conditions, including the importance of considering 3D culture environments, mechanical cues and/or media enrichment to guide differentiation into specific lineages. Metabolomic analysis has considered cell endometabolomes and exometabolomes (fingerprinting and footprinting, respectively), having measured both lipid species and polar metabolites involved in a variety of metabolic pathways. This review clearly demonstrates the current enticing promise of metabolomics in significantly contributing towards a deeper knowledge on SC behavior, and the discovery of new biomarkers of SC function with potential translation to in vivo clinical practice.

The preclinical and clinical implications of fetal adnexa derived mesenchymal stromal cells in wound healing therapy

Mesenchymal stromal cells (MSCs) isolated from fetal adnexa namely amniotic membrane/epithelium, amniotic fluid and umbilical cord have hogged the limelight in recent times, as a proposed alternative to MSCs from conventional sources. These cells which are identified as being in a developmentally primitive state have many advantages, the most important being the non-invasive nature of their isolation procedures, absence of ethical concerns, proliferation potential, differentiation abilities and low immunogenicity. In the present review, we are focusing on the potential preclinical and clinical applications of different cell types of fetal adnexa, in wound healing therapy. We also discuss the isolation-culture methods, cell surface marker expression, multi-lineage differentiation abilities, immune-modulatory capabilities and their homing property. Different mechanisms involved in the wound healing process and the role of stromal cells in therapeutic wound healing are highlighted. Further, we summarize the findings of the cell delivery systems in skin lesion models and paracrine functions of their secretome in the wound healing process. Overall, this holistic review outlines the research findings of fetal adnexa derived MSCs, their usefulness in wound healing therapy in human as well as in veterinary medicine.

Therapeutic uses of post-partum tissue-derived mesenchymal stromal cell secretome

Human post-partum tissue mesenchymal stromal cells (hPPT-MSCs) are widely used in research to investigate their differentiation capabilities and therapeutic effects as potential agents in cell-based therapy. This is ascribed to the advantages offered by the use of MSCs isolated from hPPT over other MSC sources. A paradigm shift in related research is evident that focuses on the secretome of the human MSCs (hMSCs), as therapeutic effects of hMSCs are attributed more so to their secreted growth factors, cytokines and chemokines and to the extracellular vesicles (EVs), all of which are components of the hMSC secretome. Positive therapeutic effects of the hPPT-MSC secretome have been demonstrated in diseases related to skin, kidney, heart, nervous system, cartilage and bones, that have aided fast recovery by replacing damaged, non-functional tissues, via differentiating and regenerating cells. Although certain limitations such as short half -life of the secretome components and irregular secreting patterns exist in secretome therapy, these issues are successfully addressed with the use of cutting-edge technologies such as genome editing and recombinant cytokine treatment. If the current limitations can be successfully overcome, the hPPT-MSC secretome including its EVs may be developed into a cost-effective therapeutic agent amenable to be used against a wide range of diseases/disorders.

The application of bone marrow mesenchymal stem cells and biomaterials in skeletal muscle regeneration

Skeletal muscle injuries have bothered doctors and caused great burdens to the public medical insurance system for a long time. Once injured, skeletal muscles usually go through the processes of inflammation, repairing and remodeling. If repairing and remodeling stages are out of balance, scars will be formed to replace injured skeletal muscles. At present, clinicians usually use conventional methods to restore the injured skeletal muscles, such as flap transplantation. However, flap transplantation sometimes needs to sacrifice healthy autologous tissues and will bring extra harm to patients. In recent years, stem cells-based tissue engineering provides us new treatment ideas for skeletal muscle injuries. Stem cells are cells with multiple differentiation potential and have ability to differentiate into adult cells under special condition. Skeletal muscle tissues also have stem cells, called satellite cells, but they are in small amount and new muscle fibers that derived from them may not be enough to replace injured fibers. Bone marrow mesenchymal stem cells (BM-MSCs) could promote musculoskeletal tissue regeneration and activate the myogenic differentiation of satellite cells. Biomaterial is another important factor to promote tissue regeneration and greatly enhance physiological activities of stem cells in vivo. The combined use of stem cells and biomaterials will gradually become a mainstream to restore injured skeletal muscles in the future. This review article mainly focuses on the review of research about the application of BM-MSCs and several major biomaterials in skeletal muscle regeneration over the past decades.

Regeneration of critical-sized defects, in a goat model, using a dextrin-based hydrogel associated with granular synthetic bone substitute

The development of injectable bone substitutes (IBS) have obtained great importance in the bone regeneration field, as a strategy to reach hardly accessible defects using minimally invasive techniques and able to fit to irregular topographies. In this scenario, the association of injectable hydrogels and bone graft granules is emerging as a well-established trend. Particularly, in situ forming hydrogels have arisen as a new IBS generation. An in situ forming and injectable dextrin-based hydrogel (HG) was developed, aiming to act as a carrier of granular bone substitutes and bioactive agents. In this work, the HG was associated to a granular bone substitute (Bonelike^®) and implanted in goat critical-sized calvarial defects (14 mm) for 3, 6 and 12 weeks. The results showed that HG improved the handling properties of the Bonelike^® granules and did not affect its osteoconductive features, neither impairing the bone regeneration process. Human multipotent mesenchymal stromal cells from the umbilical cord, extracellular matrix hydrolysates and the pro-angiogenic peptide LLKKK18 were also combined with the IBS. These bioactive agents did not enhance the new bone formation significantly under the conditions tested, according to micro-computed tomography and histological analysis.

Discriminating aspects of global metabolism of neonatal cardiomyocytes from wild type and KO-CSRP3 rats using proton magnetic resonance spectroscopy of culture media samples

Knockout of multifunction gene cysteine- and glycine-rich protein 3 (CSRP3) in cardiomyocytes (CMs) of mice leads to heart dilation, severely affecting its functions. In humans, CSRP3 mutations are associated with hypertrophic (HCM) and dilated cardiomyopathy (DCM). The absence of the CSRP3 expression produces unknown effects on in vitro neonatal CMs' metabolism. The metabolome changes in culture media conditioned by CSRP3 knockout (KO-CSRP3), and wild type (WT) neonatal cardiomyocytes were investigated under untreated or after metabolic challenging conditions produced by isoproterenol (ISO) stimulation, by in vitro high-resolution proton magnetic resonance spectroscopy (¹H-MRS)-based metabolomics. Metabolic differences between neonatal KO-CSRP3 and WT rats' CMs were identified. After 72 h of culture, ISO administration was associated with increased CMs' energy requirements and increased levels of threonine, alanine, and 3-hydroxybutyrate in both neonatal KO-CSRP3 and WT CMs conditioned media. When compared with KO-CSRP3, culture media derived from WT cells presented higher lactate concentrations either under basal or ISO-stimulated conditions. The higher activity of ketogenic biochemical pathways met the elevated energy requirements of the contractile cells. Both cells are considered phenotypically indistinguishable in the neonatal period of animal lives, but the observed metabolic stress responses of KO-CSRP3 and WT CMs to ISO were different. KO-CSRP3 CMs produced less lactate than WT CMs in both basal and stimulated conditions. Mainly, ISO-stimulated conditions produced evidence for lactate overload within KO-CSRP3 CMs, while WT CMs succeeded to manage the metabolic stress. Thus, ¹H-MRS-based metabolomics was suitable to identify early inefficient energetic metabolism in neonatal KO-CSRP3 CMs. These results may reflect an apparent lower lactate transport and consumption, in association with protein catabolism.

Discarded plasma obtained after cord blood volume reduction as an alternative for fetal calf serum in mesenchymal stromal cells cultures

BACKGROUND

Utilization of the fetal calf serum (FCS) carries a potential health risk and raises growing economic and ethical problems. Umbilical cord blood volume reduction, required for banking, provides clinical-grade umbilical cord blood plasma (UCBP) discarded as a waste. The aim of this study was to test whether serum derived from UCBP could replace FCS for the amplification of mesenchymal stromal cells (MSCs).

STUDY DESIGN AND METHODS

To this end, the amplification of the MSCs and mesenchymal progenitors was estimated in the presence of serum derived from UCBP and its cytokine content was determined by cytometric bead array and enzyme-linked immunosorbent assay techniques. As a comparison, other sources of clinical-grade human serum were tested in parallel: serum derived from solvent/detergent-treated fresh-frozen plasma (S/D-FFP) and from platelet (PLT)-rich and PLT-poor umbilical plasma.

RESULTS

Serum derived from UCBP-supplemented culture sustains identical amplification of MSCs and their progenitors as in the case of FCS addition. Furthermore, the assays reveal the presence in the serum derived from UCBP of cytokines influencing the properties of MSCs (basic fibroblast growth factor, transforming growth factor-β, vascular endothelial growth factor, and interleukin-8) or involved in the development of the myeloid lineage (thrombopoietin, erythropoietin, granulocyte-colony-stimulating factor, and granulocyte-macrophage-colony-stimulating factor). Also, our study indicates important differences between neonatal and adult-derived serum. Poor cytokine content in the S/D-FFP makes a less efficient replacement of FCS comparing to other human blood-derived supplements.

CONCLUSION

Our work shows that the discarded human cord blood plasma from volume reduction is an easily obtainable and greatly available, xeno-free source of serum that is a highly efficient replacement of FCS in sustaining MSC growth.

Cord blood serum harvesting by hydroxyethyl starch: a fetal bovine serum alternative in expansion of umbilical cord-derived mesenchymal stem cells

As a widely used cell culture supplement, fetal bovine serum (FBS) harbor high content of growth, proliferation, and adhesion factors. However, high cost, bio-safety, possible xenogeneic agent transmission, finite accessible, and ethical controversy are major obstacles that discourage the use of this additive. Accordingly, novel alternatives have been proposed with various pros and cons. Still, caution should be taken in choosing suitable substitute given that the alteration in the main aspects of cultured cells can be biased the consequences of clinical applications. Herein, the authors evaluated the impact of cord blood serum harvesting by hydroxyethyl starch (CBS-HES), as an enriched source of growth factors, on the basic mesenchymal stem cells (MSCs) characteristics. In the present experiment, umbilical cord-derived MSCs were isolated and continuously nourished with Dulbecco's Modified Eagle Medium containing either 10, 15, and 20% CBS-HES or FBSs to compare their morphology, immunophenotype, growth and proliferation rate, death rate, cell cycle, and gene expression profiles. Although all enriched media supported the expansion of MSCs with comparable morphology, cell surface markers, death rate, c-MYC and p16 expression, and growth rate, CBS-HES treated cells significantly (P < 0.05) expressed more hTERT gene in a concentration-dependent manner. Yet no significant shift was observed in the cell cycle of cultured cells using the same concentrations of additives, a finding which further confirmed by Ki-67 immunostaining. CBS-HES as an available and affordable additive, seems to be an optimal, relatively safe, and promising FBS alternative for cultivation, propagation, and subsequent clinical applications of MSCs.

Biological activity of mesenchymal stem cells secretome as a basis for cell-free therapeutic approach

Mesenchymal stem (stromal) cells (MSCs) are self-renewing, cultured adult stem cells which secrete a complex set of multiple soluble biologically active molecules such as chemokines, and cytokines, cell adhesion molecules, lipid mediators, interleukins (IL), growth factors (GFs), hormones, micro RNAs (miRNAs), long non-coding RNAs (lncRNAs), messenger RNAs (mRNAs), exosomes, as well as microvesicles, the secretome. MSCs of various origin, including adipose-derived stem cells (ASCs), bone marrow derived mesenchymal stem cells (BM-MSCs), human uterine cervical stem cells (hUCESCs), may be good candidates for obtaining secretome-derived products. Different population of MSCs can secret different factors which could have anti-inflammatory, anti-apoptotic, anti-fibrotic activities, a neuroprotective effect, could improve bone, muscle, liver regeneration and wound healing. Therefore, the paracrine activity of conditioned medium obtained when cultivating MSCs, due to a plethora of bioactive factors, was assumed to have the most prominent cell-free therapeutic impact and can serve as a better option in the field of regenerative medicine in future.

Antimicrobial Effects of Conditioned Medium From Amniotic Progenitor Cells in vitro and in vivo: Toward Tissue Regenerative Therapies for Bovine Mastitis

There is increasing evidence to suggest that, in addition to their regenerative effect, mesenchymal stromal cells (MSCs), and their secretome have an anti-inflammatory and antimicrobial role in the innate immune response in conditions such as sepsis. However, there is no published information on the effect of MSCs in bovine mastitis. Mastitis often results in extensive tissue damage due to multi-microorganism co-infection. This study investigated the ability of amniotic-derived conditioned medium (CM), in vitro and in vivo, to counteract microbial action and restore healthy tissue capable of milk production. Following determination of a dose–response curve, 10,000 colony-forming units (CFU) of Staphylococcus aureus (S. aureus) were inoculated into bovine mammary epithelial cell culture with and without 10% CM (supplemented either at the time of bacteria inoculation or after 4 h). Acridine orange staining was used to assess cell viability/apoptosis. Additionally, an in vivo study was performed using 48 dairy cows with acute and chronic mastitis, treated with CM (treated group) or antibiotics (control group). In vitro results showed that CM can attenuate bacterial growth, as evaluated by the number of CFU. After 24 h of culture with S. aureus, 89.67% of mammary epithelial cells treated with CM were still alive, whereas all cells cultured without CM were dead. Rates of epithelial cell survival (60.67%) were similar when CM was added 4 h after bacteria inoculation. There was no difference in somatic cell count between cases of acute mastitis in the CM-treated or control group in the in vivo study. However, relapses in chronic mastitis were less common in the group receiving CM. Our results show that CM is able to mitigate bacterial growth in vitro and may be particularly useful in the treatment of chronic mastitis, aiding restoration of milk production in cows that would otherwise be removed from the production cycle.

Mesenchymal Stem/ Stromal Cells metabolomic and bioactive factors profiles: A comparative analysis on the umbilical cord and dental pulp derived Stem/ Stromal Cells secretome

Mesenchymal Stem/ Stromal Cells assume a supporting role to the intrinsic mechanisms of tissue regeneration, a feature mostly assigned to the contents of their secretome. A comparative study on the metabolomic and bioactive molecules/factors content of the secretome of Mesenchymal Stem/ Stromal Cells derived from two expanding sources: the umbilical cord stroma and the dental pulp is presented and discussed. The metabolic profile (Nuclear Magnetic Resonance Spectroscopy) evidenced some differences in the metabolite dynamics through the conditioning period, particularly on the glucose metabolism. Despite, overall similar profiles are suggested. More prominent differences are highlighted for the bioactive factors (Multiplexing Laser Bear Analysis), in which Follistatin, Growth Regulates Protein, Hepatocyte Growth Factor, Interleukin-8 and Monocyte Chemotactic Protein-1 dominate in Umbilical Cord Mesenchymal Stem/ Stromal Cells secretion, while in Dental Pulp Stem/ Stromal Cells the Vascular Endothelial Growth Factor-A and Follistatin are more evident. The distinct secretory cocktail did not result in significantly different effects on endothelial cell populations dynamics including proliferation, migration, tube formation capacity and in vivo angiogenesis, or in chemotaxis for both Mesenchymal Stem/ Stromal Cells populations.

Human Umbilical Cord Blood Serum/Plasma: Cytokine Profile and Prospective Application in Regenerative Medicine

The concentrations of cytokines and growth factors in human umbilical cord blood serum and plasma samples were measured by multiplex analysis. It was found that in comparison with peripheral blood serum of adult donors, umbilical cord blood serum and plasma contain significantly higher concentrations of the most studied molecules including IL-4, 5, 6, 7, 10 and 15, MCP-1, SCF, and SDF, as well as growth factors directly involved in the processes of regeneration (G-CSF, HGF, PDGF-BB, and VEGF). Thus, umbilical cord blood plasma and especially serum are a rich source of cytokines and growth factors with anti-inflammatory, anti-apoptotic, and angiogenic effects and can be used in various fields of regenerative medicine.

A Comparison of Phenotypic and Functional Properties of Mesenchymal Stromal Cells and Multipotent Adult Progenitor Cells

Both Multipotent Adult Progenitor Cells and Mesenchymal Stromal Cells are bone-marrow derived, non-haematopoietic adherent cells, that are well-known for having immunomodulatory and pro-angiogenic properties, whilst being relatively non-immunogenic. However, they are phenotypically and functionally distinct cell types, which has implications for their efficacy in different settings. In this review we compare the phenotypic and functional properties of these two cell types, to help in determining which would be the superior cell type for different applications.

Mesenchymal Stem Cells in Homeostasis and Systemic Diseases: Hypothesis, Evidences, and Therapeutic Opportunities

Mesenchymal stem cells (MSCs) are present in all organs and tissues, playing a well-known function in tissue regeneration. However, there is also evidence indicating a broader role of MSCs in tissue homeostasis. In vivo studies have shown MSC paracrine mechanisms displaying proliferative, immunoregulatory, anti-oxidative, or angiogenic activity. In addition, recent studies also demonstrate that depletion and/or dysfunction of MSCs are associated with several systemic diseases, such as lupus, diabetes, psoriasis, and rheumatoid arthritis, as well as with aging and frailty syndrome. In this review, we hypothesize about the role of MSCs as keepers of tissue homeostasis as well as modulators in a variety of inflammatory and degenerative systemic diseases. This scenario opens the possibility for the use of secretome-derived products from MSCs as new therapeutic agents in order to restore tissue homeostasis, instead of the classical paradigm "one disease, one drug".

An in vitro long-term study of cryopreserved umbilical cord blood-derived platelet-rich plasma containing growth factors-PDGF-BB, TGF-β, and VEGF

PURPOSE

Umbilical cord blood-derived platelet-rich plasma (UCB-PRP) containing growth factors has attracted attention as a biomaterial useful for regenerative medicine. The osteoblastic differentiation of umbilical cord-derived mesenchymal stromal cells (UC-MSCs) can be induced by UCB-PRP.

MATERIALS AND METHODS

Nine samples of UC and UCB were used to conduct an in vitro study that determined the contents of three growth factors (i.e., platelet-derived growth factor, transforming growth factor β-1, and vascular endothelial growth factor) and that examined, by staining with Alizarin red, their ability to induce the osteoblastic differentiation of UC-MSCs at the baseline, 3 months, and 3 years of cryopreservation.

RESULTS

The contents of growth factors in cryopreserved UCB-PRP were markedly elevated compared to those found in UCB at baseline. The samples of UCB that were added with cryopreserved UCB-PRP and those with bone morphogenetic protein-2 were stained granularly with Alizarin red, thus indicating the presence of calcium. The samples of UCB that were not added with UCB-PRP were not stained with Alizarin red. The above-mentioned contents and ability were maintained at 3 years of cryopreservation. Cryopreserved UCB-PRP possibly and advantageously induced the osteoblastic differentiation of UC-MSCs.

CONCLUSION

The potential clinical application of cryopreserved UCB-PRP to regenerative medicine was suggested.

Dental pulp stem cells and Bonelike® for bone regeneration in ovine model

Development of synthetic bone substitutes has arisen as a major research interest in the need to find an alternative to autologous bone grafts. Using an ovine model, the present pre-clinical study presents a synthetic bone graft (Bonelike^®) in combination with a cellular system as an alternative for the regeneration of non-critical defects. The association of biomaterials and cell-based therapies is a promising strategy for bone tissue engineering. Mesenchymal stem cells (MSCs) from human dental pulp have demonstrated both in vitro and in vivo to interact with diverse biomaterial systems and promote mineral deposition, aiming at the reconstruction of osseous defects. Moreover, these cells can be found and isolated from many species. Non-critical bone defects were treated with Bonelike^® with or without MSCs obtained from the human dental pulp. Results showed that Bonelike^® and MSCs treated defects showed improved bone regeneration compared with the defects treated with Bonelike^® alone. Also, it was observed that the biomaterial matrix was reabsorbed and gradually replaced by new bone during the healing process. We therefore propose this combination as an efficient binomial strategy that promotes bone growth and vascularization in non-critical bone defects.

Mesenchymal Stromal Cell Secretome: Influencing Therapeutic Potential by Cellular Pre-conditioning

Mesenchymal stromal cells (MSCs) are self-renewing, culture-expandable adult stem cells that have been isolated from a variety of tissues, and possess multipotent differentiation capacity, immunomodulatory properties, and are relatively non-immunogenic. Due to this unique set of characteristics, these cells have attracted great interest in the field of regenerative medicine and have been shown to possess pronounced therapeutic potential in many different pathologies. MSCs' mode of action involves a strong paracrine component resulting from the high levels of bioactive molecules they secrete in response to the local microenvironment. For this reason, MSCs' secretome is currently being explored in several clinical contexts, either using MSC-conditioned media (CM) or purified MSC-derived extracellular vesicles (EVs) to modulate tissue response to a wide array of injuries. Rather than being a constant mixture of molecular factors, MSCs' secretome is known to be dependent on the diverse stimuli present in the microenvironment that MSCs encounter. As such, the composition of the MSCs' secretome can be modulated by preconditioning the MSCs during in vitro culture. This manuscript reviews the existent literature on how preconditioning of MSCs affects the therapeutic potential of their secretome, focusing on MSCs' immunomodulatory and regenerative features, thereby providing new insights for the therapeutic use of MSCs' secretome.

Cytokines in umbilical cord blood-derived cellular product: a mechanistic insight into bone repair

AIM

Umbilical cord blood (UCB) finds frequent applications in regenerative medicine. We evaluated the role of cytokines present in a uniquely processed, UCB-derived cellular allograft product (UCBp).

MATERIALS & METHODS

Luminex multiplex assay and standard cell biology methods were employed.

RESULTS

Study with allografts from 33 donors identified 44 quantifiable cytokines in the UCBp derived conditioned media (CM). The UCBp-CM elevated proliferation and migration rates of mesenchymal stem cells (MSCs) and bone marrow stromal cells. Moreover, UCBp-CM induced secretion of VEGF-A and osteoprotegerin, which promoted angiogenesis of endothelial cells and positively influenced the osteogenic differentiation of MSCs, respectively.

CONCLUSION

Cytokines in UCBp stimulate cellular processes important for bone regeneration, making UCBp an excellent candidate for potential applications in orthopedic procedures like bone non-union and spinal fusion.

Can mesenchymal stem cells and their conditioned medium assist inflammatory chondrocytes recovery?

Osteoarthritis (OA), one of the most common joint disease, affects more than 80% of the population aged 70 or over. Mesenchymal stem cells (MSCs) show multi-potent differentiation and self-renewal capability, and, after exposure to an inflammatory environment, also exhibit immunosuppressive properties. In this study, we have used a model of lipopolysaccharide (LPS)-stimulated chondrocytes to evaluate MSC anti-inflammatory efficacy. The anti-inflammatory mechanism was tested in two cell-contained culture systems: (i) MSC-chondrocyte indirect contact system and (ii) MSC-chondrocyte direct contact system, and one cytokine-only culture system: MSC-conditioned medium (CM) system. Results showed that MSCs reduced chondrocyte inflammation through both paracrine secretion and cell-to-cell contact. The inflammation-associated, and free-radical-related genes were down-regulated significantly in the direct contact system on 24 h, however, the TNF-α. IL-6 were upregulated and aggrecan, COLII were downregulated on 72 h in direct contact system. Moreover, we found CM produced by MSC possess well therapeutic effect on inflammatory chondorcyte, and the 10-fold concentrated MSC-conditioned medium could down-regulated chondorcyte synthesis inflammation-associated, and free-radical-related genes, such as TNF-α, IL-1β, IL-6 and iNOS even treated for 72 h. In conclusion, MSC-CM showed great potential for MSC-based therapy for OA.

Plasma derived from human umbilical cord blood: Potential cell-additive or cell-substitute therapeutic for neurodegenerative diseases

Limited efficacy of current therapeutic approaches for neurodegenerative disease has led to increased interest in alternative therapies. Cord blood plasma (CBP) derived from human umbilical cord blood (hUCB) may be a potential therapeutic. Benefits of CBP injection into rodent models of aging or ischaemic stroke have been demonstrated, though how benefits are elicited is still unclear. The present study evaluated various factors within the same samples of CBP and human adult blood plasma/sera (ABP/S). Also, autologous CBP effects vs. ABP/S or foetal bovine serum supplements on mononuclear cells from hUCB (MNC hUCB) in vitro were determined. Results showed significantly low concentrations of pro-inflammatory cytokines (IL-2, IL-6, IFN-γ, and TNF-α) and elevated chemokine IL-8 in CBP. Significantly higher levels of VEGF, G-CSF, EGF and FGF-basic growth factors were determined in CBP vs. ABP/S. Autologous CBP media supplements significantly increased MNC hUCB viability and decreased apoptotic cell activity. We are first to demonstrate the unique CBP composition of cytokines and growth factors within the same CBP samples derived from hUCB. Also, our novel finding that autologous CBP promoted MNC hUCB viability and reduced apoptotic cell death in vitro supports CBP's potential as a sole therapeutic or cell-additive agent in developing therapies for various neurodegenerative diseases.

Human umbilical cord blood plasma as an alternative to animal sera for mesenchymal stromal cells in vitro expansion - A multicomponent metabolomic analysis

Mesenchymal Stromal cells (MSCs) have a potential role in cell-based therapies. Foetal bovine serum (FBS) is used to supplement the basal cell culture medium but presents several disadvantages and risks. Other alternatives have been studied, including human umbilical cord blood plasma (hUCBP), aiming at the development of xeno-free culturing protocols. A comparative characterization of multicomponent metabolic composition of hUCBP and commercial FBS based on Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate statistical analysis was performed. The analysis of ¹H-NMR spectra revealed both similarities and differences between the two proposed supplements. Similar metabolites (amino acids, glucose, lipids and nucleotides) were found in the hUCBP and FBS NMR spectra. The results show that the major difference between the metabolic profiles of the two proposed supplements are due to the significantly higher levels of glucose and lower levels of lactate, glutamate, alanine and branched chain amino acids in hUCBP. Similar or slightly different levels of important proteinogenic amino acids, as well as of nucleotides, lipids were found in the hUCBP and FBS. In order to validate it’s suitability for cell culture, umbilical cord-MSCs (UC-MSCs) and dental pulp stem cells (DPSCs) were expanded using hUCBP. In both hMSCs, in vitro culture with hUCBP supplementation presented similar to improved metabolic performances when compared to FBS. The two cell types tested expressed different optimum hUCBP percentage content. For DPSCs, the optimum hUCBP content was 6% and for UC-MSCs, 4%. Cultured hMSCs displayed no changes in senescence indicators, as well as maintained characteristic surface marker’s expression. FBS substitution was associated with an increase in early apoptosis events, in a dose dependent manner, as well as to slight up- and down-regulation of targeted gene’s expression. Tri-lineage differentiation capacity was also influenced by the substitution of FBS by hUCBP.

CD73, CD90, CD105 and Cadherin-11 RT-PCR Screening for Mesenchymal Stem Cells from Cryopreserved Human Cord Tissue

Background and Objectives

Mesenchymal stem cells (MSCs) are self-renewing, non-specialized cells used clinically in tissue regeneration and sourced from bone marrow, peripheral blood, umbilical cord blood and umbilical cord tissue (UCT). To demonstrate an alternative method for MSC detection, cryopreserved UCT and expanded MSC were screened for MSC markers CD73, CD90, CD105 and CDH-11 by RT-PCR.

Methods and Results

Human UCT were washed, sectioned, cryopreserved with 10% DMSO and stored in the vapor phase of liquid nitrogen. Fresh and frozen UCT samples were expanded for MSC. UCT and MSC were processed for RNA and screened for CD73, CD90, CD105 and CDH-11 mRNA by RT-PCR. CD73, CD90 and CD105 were detected by flow cytometry and CDH-11 was detected by Western blotting. Short and long-term frozen UCT shows a loss of mRNA expression for CD73 at 33.2±34.0%, CD90 at 6.2±8.2%, CD105 at 17.7±21.6% and CDH-11 at 30.1±26.7% but was not statistically significant to indicate the deterioration. Expanded MSCs from fresh UCT expressed 0.09±0.07-fold CD73, 0.17±0.11-fold CD90, 0.04±0.06-fold CD105 and 0.14±0.08-fold CDH-11. Expanded MSCs from frozen UCTs expressed 0.09±0.06-fold CD73, 0.13±0.06-fold CD90, 0.04±0.05-fold CD105 and 0.11±0.06-fold CDH-11 and confirmed by flow cytometry and Western blotting.

Conclusion

CD73, CD90, CD105 and CDH-11 were detected by RT-PCR in cryopreserved UCT and MSC expansion. CDH-11 appears as a useful single target MSC marker for quick screening.

Modeling and analysis of biomagnetic blood Carreau fluid flow through a stenosis artery with magnetic heat transfer: A transient study

We present a numerical investigation of tapered arteries that addresses the transient simulation of non-Newtonian bio-magnetic fluid dynamics (BFD) of blood through a stenosis artery in the presence of a transverse magnetic field. The current model is consistent with ferro-hydrodynamic (FHD) and magneto-hydrodynamic (MHD) principles. In the present work, blood in small arteries is analyzed using the Carreau-Yasuda model. The arterial wall is assumed to be fixed with cosine geometry for the stenosis. A parametric study was conducted to reveal the effects of the stenosis intensity and the Hartman number on a wide range of flow parameters, such as the flow velocity, temperature, and wall shear stress. Current findings are in a good agreement with recent findings in previous research studies. The results show that wall temperature control can keep the blood in its ideal blood temperature range (below 40°C) and that a severe pressure drop occurs for blockages of more than 60 percent. Additionally, with an increase in the Ha number, a velocity drop in the blood vessel is experienced.

Therapeutic effects of umbilical cord blood plasma in a rat model of acute ischemic stroke

Umbilical cord blood plasma (UCB-PL) contains various cytokines, growth factors, and immune modulatory factors that regulate the proliferation and function of immune cells and adult stem cells. Despite its therapeutic potential, the effects of UCB-PL treatment in conditions of ischemic brain injury have yet to be investigated. In this study, we demonstrated that both behavioral and structural impairments resulting from ischemic brain injury were significantly prevented/reversed after intravenous administration of UCB-PL relative to the vehicle control. As early as 1-week post-ischemia, an increased number of newborn cells in the subventricular zone and a reduced number of activated microglial cells in the peri-infarct area were observed in the UCB-PL group, suggesting that enhanced neurogenesis and/or the suppression of inflammation may have contributed to functional protection/recovery. Moreover, UCB-PL was more effective than plasma derived from a 65-year-old healthy adult for the treatment of ischemia-related structural and functional deficits, indicating that UCB-PL had greater therapeutic potential. This study provides valuable insights into the development of a safe, effective, and cell-free strategy for the treatment of ischemic brain damage and a much-needed alternative for patients who are ineligible for thrombolytic therapy.

Secretome derived from different cell lines in bovine embryo production in vitro

The present study investigated the effects of conditioned medium (CM), composed of microvesicles (MVs) and soluble factors present in the supernatant (SN), of bovine endometrial and amniotic cells on embryo quality and rate of blastocyst production. Presumptive zygotes were randomly assigned on Days 1, 3 and 5 after fertilisation to synthetic oviducal fluid with amino acids (SOFaa; control) or to SOFaa supplemented with either 20% endometrial or amniotic CM, 20% SN or 100 × 106 MVs mL−1. Embryos were evaluated on Day 7. For groups supplemented with MVs derived from either endometrial or amniotic cells on Day 1 of culture, blastocysts had developed, but at a lower rate than in the control group. Blastocysts had developed in all groups in which endometrial or amniotic cell-derived CM or MVs were added on Day 3 of culture, but the rate of blastocyst development was significantly lower in both CM groups than in the MVs groups. The addition of all secretome fractions (CM, MVs and SN) derived from either bovine endometrial or amniotic cells on Day 5 of culture resulted in blastocyst production, but only amniotic MVs resulted in a blastocyst production rate comparable to that in the control group. Supplementation of SOFaa on Day 5 resulted in a qualitatively higher number of inner cell mass cells compared with the control group only for the amniotic CM and MVs groups. At day 7, these data were confirmed by RT-qPCR evaluation of genes (Bcl-2-associated X protein (BAX) and glutathione peroxidase 1 (GPX1) involved in apoptosis and protection against reactive oxygen species. In conclusion, of the different secretome fractions tested, only amniotic MVs added to SOFaa resulted in better outcomes than in the control group.

Evaluation of PVA biodegradable electric conductive membranes for nerve regeneration in axonotmesis injuries: the rat sciatic nerve animal model

The therapeutic effect of three polyvinyl alcohol (PVA) membranes loaded with electrically conductive materials - carbon nanotubes (PVA-CNTs) and polypyrrole (PVA-PPy) - were tested in vivo for neuro-muscular regeneration after an axonotmesis injury in the rat sciatic nerve. The membranes electrical conductivity measured was 1.5 ± 0.5 × 10^-6 S/m, 579 ± 0.6 × 10^-6 S/m, and 1837.5 ± 0.7 × 10^-6 S/m, respectively. At week-12, a residual motor and nociceptive deficit were present in all treated groups, but at week-12, a better recovery to normal gait pattern of the PVA-CNTs and PVA-PPy treated groups was observed. Morphometrical analysis demonstrated that PVA-CNTs group presented higher myelin thickness and lower g-ratio. The tibialis anterior muscle, in the PVA-PPy and PVA-CNTs groups showed a 9% and 19% increase of average fiber size area and a 5% and 10% increase of the "minimal Feret's diameter," respectively. No inflammation, degeneration, fibrosis or necrosis were detected in lung, liver, kidneys, spleen, and regional lymph nodes and absence of carbon deposits was confirmed with Von Kossa and Masson-Fontana stains. In conclusion, the membranes of PVA-CNTs and PVA-PPy are biocompatible and have electrical conductivity. The higher electrical conductivity measured in PVA-CNTs membrane might be responsible for the positive results on maturation of myelinated fibers. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1267-1280, 2017.

Analysis of Proliferation of Melanoma Cells and Mesenchymal Stem Cells in Co-Culture and Contribution of Experimental Conditions into Interpretation of the Results

A series of experiments on co-culturing of Mel IL melanoma cells and mesenhymal stem cells showed that these cells do not influence proliferation of each other, but we observed weaker adhesion of stromal stem cells to plastic in cocultures where with melanoma cells were grown on mesenhymal stem cells feeder. Cell proliferation was also considerably influenced by experimental conditions, which should be taken into account for correct interpretation of obtained results. The principles of experiments on co-culturing of cancer and stromal cells are formulated that take into account the most important factors influencing cell behavior and minimize the probability of artifact results. It was concluded that co-culturing conditions cells significantly affect the experimental results and can be the source of conflicting conclusions on mutual influence of stromal and cancer cells in vitro.

Inflammatory response to dextrin-based hydrogel associated with human mesenchymal stem cells, urinary bladder matrix and Bonelike® granules in rat subcutaneous implants

Increasing relevance has been attributed to hydrogels due to their ability to provide an extracellular matrix (ECM)-like environment for cellular adhesion and proliferation, acting as mechanical scaffolds for tissue remodeling or as delivery matrices. In vivo biocompatibility of a hybrid dextrin hydrogel produced from oxidized dextrin and adipic acid dihydrazide and its combinations with human mesenchymal stem cells (hMSCs), ECM from a porcine bladder (urinary bladder matrix) and ceramic granules (Bonelike^®), was evaluated following ISO 10993 after subcutaneous implantation in a rat model. Histological analysis after 3 and 15 d showed typical acute and chronic inflammatory responses, respectively, with a more severe reaction exhibited whenever the ceramic granules were present. However, the dextrin hydrogel was able to stabilize granules in the implant site. Dextrin hydrogel was scored as slight irritant after 3 d, similar to its combination with UBM, and as non-irritant after 15 d. The presence of viable hMSCs in the subcutaneous tissue could be confirmed by the presence of anti-human nuclei antibody (HuNu⁺) cells. The production of growth factors and inflammatory and immunomodulatory cytokines by these cells was also quantified in peripheral blood confirming the successful encapsulation of hMSCs into the hydrogel matrix for cell survival promotion. The presence of hMSCs seemed to modulate the inflammatory response by accelerating its progression when compared to the acellular experimental groups. Dextrin hydrogel has proven to be a biocompatible multifunctional matrix for minimally invasive biomedical procedures, including orthopedic surgeries when associated with bone substitutes and also as a possible encapsulation matrix for cell-based therapies.

Conditioned Medium from Placental Mesenchymal Stem Cells Reduces Oxidative Stress during the Cryopreservation of Ex Vivo Expanded Umbilical Cord Blood Cells

Background

The limited cell dose in umbilical cord blood (UCB) necessitates ex vivo expansion of UCB. Further, the effective cryopreservation of these expanded cells is important in widening their use in the clinics. During cryopreservation, cells experience oxidative stress due to the generation of reactive oxygen species (ROS). Conditioned medium from mesenchymal stem cells (MSCs-CM) has been shown to alleviate the oxidative stress during wound healing, Alzheimer’s disease and ischemic disease. This premise prompted us to investigate the influence of MSCs-CM during cryopreservation of expanded UCB cells.

Methodology/Principle findings

CM-was collected from cord/placental MSCs(C-MSCs-CM, P-MSC-CM). UCB CD34⁺cells were expanded as suspension cultures in serum free medium containing cytokines for 10 days. Cells were frozen with/without C-MSCs-CM and or P-MSCs-CM in the conventional freezing medium containing 20%FCS +10%DMSO using a programmable freezer and stored in liquid nitrogen. Upon revival, cells frozen with MSCs-CM were found to be superior to cells frozen in conventional medium in terms of viability, CD34⁺content and clonogenecity. Priming of revived cells for 48 hrs with MSCs-CM further improved their transplantation ability, as compared to those cultured without MSCs-CM. P-MSCs-CM radically reduced the oxidative stress in cryopreserved cells, resulting in better post thaw functionality of CD34⁺ cells than with C-MSCs-CM. The observed cryoprotective effect of MSCs-CM was primarily due to anti-oxidative and anti-apoptotic properties of the MSCs-CM and not because of the exosomes secreted by them.

Conclusions/Significance

Our data suggest that MSCs-CM can serve as a valuable additive to the freezing or the priming medium for expanded UCB cells, which would increase their clinical applicability.

Mesenchymal stem cells enhance the metastasis of 3D-cultured hepatocellular carcinoma cells

Background

Accumulating evidences have demonstrated that mesenchymal stem cells (MSC) could be recruited to the tumor microenvironment. Umbilical cord mesenchymal stem cells (UCMSC) were attractive vehicles for delivering therapeutic agents against cancer. Nevertheless, the safety of UCMSC in the treatment of tumors including hepatocellular carcinoma (HCC) was still undetermined.

Methods

In this study, an in vitro co-culture system was established to evaluate the effect of UCMSC on the cell growth, cancer stem cell (CSC) characteristics, drug resistance, metastasis of 3D-cultured HCC cells, and the underlying mechanism was also investigated.

Results

It was found that after co-cultured with UCMSC, the metastatic ability of 3D-cultured HCC cells was significantly enhanced as indicated by up-regulation of matrix metalloproteinase (MMP), epithelial-mesenchymal transition (EMT)-related genes, and migration ability. However, cell growth, drug resistance and CSC-related gene expression of HCC cells were not affected by UCMSC. Moreover, EMT was reversed, MMP-2 expression was down-regulated, and migration ability of HCC cell was significantly inhibited when TGF-β receptor inhibitor SB431542 was added into the co-culture system.

Conclusions

Therefore, these data indicated that UCMSC could significantly enhance the tumor cell metastasis, which was due to the EMT of HCC cells induced by TGF-β.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2595-4) contains supplementary material, which is available to authorized users.

Secretome from resident cardiac stromal cells stimulates proliferation, cardiomyogenesis and angiogenesis of progenitor cells

In the heart, tissue-derived signals play a central role on recruiting/activating stem cell sources to induce cardiac lineage specification for maintenance of tissue homeostasis and repair. Cardiac resident stromal cells (CRSCs) may play a pivotal role in cardiac repair throughout their secretome. Here, we performed the characterization of CRSCs and their secretome by analyzing the composition of their culture-derived extracellular matrix (ECM) and conditioned medium (CM) and by investigating their potential effect on adipose-derived stem cell (ADSC) and progenitor cell behavior. We confirmed that CRSCs are a heterogeneous cell population whose secretome is composed by proteins related to cellular growth, immune response and cardiovascular development and function. We also observed that CRSC secretome was unable to change the behavior of ADSCs, except for proliferation. Additionally, CM from CRSCs demonstrated the potential to drive proliferation and cardiac differentiation of H9c2 cells and also the ability to induce angiogenesis in vitro. Our data suggest that the CRSCs can be a source of important modulating signals for cardiac progenitor cell recruitment/activation.

Metabolomics as a Challenging Approach for Medicinal Chemistry and Personalized Medicine

"Omics" sciences have been developed to provide a holistic point of view of biology and to better understand the complexity of an organism as a whole. These systems biology approaches can be examined at different levels, starting from the most fundamental, i.e., the genome, and finishing with the most functional, i.e., the metabolome. Similar to how genomics is applied to the exploration of DNA, metabolomics is the qualitative and quantitative study of metabolites. This emerging field is clearly linked to genomics, transcriptomics, and proteomics. In addition, metabolomics provides a unique and direct vision of the functional outcome of an organism's activities that are required for it to survive, grow, and respond to internal and external stimuli or stress, e.g., pathologies and drugs. The links between metabolic changes, patient phenotype, physiological and/or pathological status, and treatment are now well established and have opened a new area for the application of metabolomics in the drug discovery process and in personalized medicine.

Neuromuscular Regeneration: Perspective on the Application of Mesenchymal Stem Cells and Their Secretion Products

Mesenchymal stem cells are posing as a promising character in the most recent therapeutic strategies and, since their discovery, extensive knowledge on their features and functions has been gained. In recent years, innovative sources have been disclosed in alternative to the bone marrow, conveying their associated ethical concerns and ease of harvest, such as the umbilical cord tissue and the dental pulp. These are also amenable of cryopreservation and thawing for desired purposes, in benefit of the donor itself or other patients in pressing need. These sources present promising possibilities in becoming useful cell sources for therapeutic applications in the forthcoming years. Effective and potential applications of these cellular-based strategies for the regeneration of peripheral nerve are overviewed, documenting recent advances and identified issues for this research area in the near future. Finally, besides the differentiation capacities attributed to mesenchymal stem cells, advances in the recognition of their effective mode of action in the regenerative theatre have led to a new area of interest: the mesenchymal stem cells' secretome. The paracrine modulatory pathway appears to be a major mechanism by which these are beneficial to nerve regeneration and comprehension on the specific growth factors, cytokine, and extracellular molecules secretion profiles is therefore of great interest.

Therapeutic Effects of Umbilical Cord Blood Derived Mesenchymal Stem Cell-Conditioned Medium on Pulmonary Arterial Hypertension in Rats

Background:

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) may have multiple therapeutic applications for cell based therapy including the treatment of pulmonary artery hypertension (PAH). As low survival rates and potential tumorigenicity of implanted cells could undermine the mesenchymal stem cell (MSC) cell-based therapy, we chose to investigate the use of conditioned medium (CM) from a culture of MSC cells as a feasible alternative.

Methods:

CM was prepared by culturing hUCB-MSCs in three-dimensional spheroids. In a rat model of PAH induced by monocrotaline, we infused CM or the control unconditioned culture media via the tail-vein of 6-week-old Sprague-Dawley rats.

Results:

Compared with the control unconditioned media, CM infusion reduced the ventricular pressure, the right ventricle/(left ventricle+interventricular septum) ratio, and maintained respiratory function in the treated animals. Also, the number of interleukin 1α (IL-1α), chemokine (C-C motif) ligand 5 (CCL5), and tissue inhibitor of metalloproteinase 1 (TIMP-1)–positive cells increased in lung samples and the number of terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling technique (TUNEL)–positive cells decreased significantly in the CM treated animals.

Conclusions:

From our in vivo data in the rat model, the observed decreases in the TUNEL staining suggest a potential therapeutic benefit of the CM in ameliorating PAH-mediated lung tissue damage. Increased IL-1α, CCL5, and TIMP-1 levels may play important roles in this regard.