Passage 1 Research Articles

THE IMMUNOMODULATORY EFFECT OF UMBILICAL CORD MESENCHYMAL STEM CELLS PRODUCED UNDER XENO-FREE CONDITIONS

<h3>Background</h3> Mesenchymal stem cells (MSC) are promising in cell therapy especially for their paracrine action and immunomodulatory and anti-inflammatory functions. However, for clinical application, these cells need to expand in vitro to achieve enough number for therapy. Most of the studies for MSC expansion use xenogeneic products. In order to provide a safe therapy, using animal protein-free products have been considered. In this study it was evaluated the immunomodulatory potential of umbilical cord MSC (UC-MSC) using xeno-free expansion conditions compared with UC-MSC expansion using animal derived components. <h3>Methods</h3> Six samples of UC-MSC were isolated and expanded until passage 3 (P3), under xeno-free conditions and with animal derived components. Immunomodulation was evaluated by lymphocyte proliferation assay where MSC suppress peripheral blood mononuclear cell (PBMC) proliferation. <h3>Results</h3> UC-MSC cultured under the xeno-free conditions, were able to inhibit 37.69% of T lymphocyte proliferation, in the ratio 1:2 (PBMC:MSC), 65.33% in 1:5 and 78.04% in 1:10. In the protocol using animal derived components, the MSC inhibitory capacity was 74.33% in the ratio 1:2, 74.60% in 1:5 and 79.61% in 1:10. The inhibitory capacity of UC-MSC in the ratio 1:2, was statistically significantly lower in xeno-free conditions than in the protocol using animal derived components (<i>p</i>=0.004). In ratios 1:5 and 1:10, the inhibitory capacity was similar, with no statistical difference (<i>p</i>=0.238 and p=0.792, respectively). <h3>Conclusion</h3> The inhibitory capacity of UC-MSC in the ratio 1:2 was insufficient in the xeno-free conditions, because UC-MSC inhibit less than 50% of T cells, that is under the criteria established for clinical use, which must be ≥ 50%. The T lymphocyte proliferation assay showed that a greater number of MSC in xeno-free conditions is necessary for an effective immunosuppression. The study showed that UC-MSC culture under xeno-free conditions reduced the immunomodulatory potential of these cells.

CELLULAR AND MOLECULAR CHARACTERIZATION OF MESENCHYMAL STEM CELLS DERIVED FROM PLURIPOTENT STEM CELLS AND PROSPECTION OF APPLICATIONS IN REGENERATIVE MEDICINE

<h3>Background</h3> Stem cells have been studied for their properties on tissue regeneration and functional recovery of injured organs. Mesenchymal stem cells (MSCs) are prominent in this context as they promote the increase of activity and viability of several cell types through distinct mechanisms. However, biological samples of MSCs bring great variability in behavior and viability while in culture (e.g., cell population heterogeneity, senescence). Therefore, it is necessary to establish a standardized protocol for the generation of high-quality stable cell cultures. In this sense, the use of pluripotent stem cells (PSCs) in derivation protocols for generation of MSC-like cells (PSC-MSCs) is an alternative, since PSCs maintain their characteristics consistently under suitable culture conditions. <h3>Methods</h3> Pluripotent stem cells (HES3) grown as cell clumps were cultured in ultralow attachment plates in aggregation medium for 24 h under hypoxia to form embryoid bodies (EBs). Mesodermal differentiation was induced in the EBs during 4 days when CD56 mesodermal marker was evaluated by FACS. Induced EBs were then plated into gelatin coatings and cultured in standard MSC medium containing FBS. After 4 passages the generated cells were evaluated for classical positive and negative MSC markers as defined by ISCT. <h3>Results</h3> Mesoderm induction was observed in induced EBs by CD56 expression (78%). During culture in FBS-containing medium, EBs attached and migrating cells presented fibroblast-like morphology. With progression of culture PSC-MSCs acquired epithelial-like morphology and slowly retrieved fibroblast-like morphology until passage 4 (P4). FACS analysis in P4 identified positive MSC markers CD90/CD140b in the majority of PSC-MSCs, and CD73/CD13 present in about one third of the cells. CD105 expression was not detected. Negative MSC markers CD34/CD11b/CD45/CD19/CD31/HLA-DR were not expressed by PSC-MSCs as well. About 26% of the cells expressed CD90 and CD73 simultaneously. Half of the analyzed cells still expressed CD56, indicating PSC-MSC may be less mature than adult MSCs. <h3>Conclusion</h3> PSC-MSC derivation protocol via mesodermal induction is feasible and the generated cells expressed positive MSC markers and lacked the negative ones. PSC-MSC were expanded <i>in vitro</i> for at least four passages. Further investigations will analyze other minimal criteria of MSC in the derived cells as trilineage differentiation potential, besides transcriptomic and karyotyping analysis.

Motorized Shaver Harvest Results in Similar Cell Yield and Characteristics Compared With Rongeur Biopsy During Arthroscopic Synovium-Derived Mesenchymal Stem Cell Harvest

<h3>Purpose</h3> To compare cell yield and character of synovium-derived mesenchymal stem cell (SDMSC) harvested by 2 different techniques using rongeur and motorized shaver during knee arthroscopy. <h3>Methods</h3> This study was performed in 15 patients undergoing partial meniscectomy. Two different techniques were used to harvest SDMSCs in each patient from the synovial membrane at 2 different locations overlying the anterior fat pad, each within 1 minute of harvest time. Cell yield and proliferation rates were evaluated. Cell surface marker analysis was done after passage 2 (P2). Trilineage differentiation potential was evaluated by real-time quantitative polymerase chain reaction and histology. Statistical analysis between the 2 methods was done using the Mann–Whitney <i>U</i> test. <h3>Results</h3> Wet weight of total harvested tissue was 69.93 (± 20.02) mg versus 378.91 (± 168.87) mg for the rongeur and shaver group, respectively (<i>P</i> < .0001). Mononucleated cell yield was 3.32 (± 0.89) versus 3.18 (± 0.97) × 10³ cells/mg, respectively (<i>P</i> = .67). Fluorescence-activated cell sorting analysis revealed similar SDMSC-related cell surface marker expression levels in both groups, with positive expression for CD44, CD73, CD90, and CD105 and decreased expression for CD34 and CD45. Both groups showed similar trilineage differentiation potential in histology. Chondrogenic (SOX9, ACAN, COL2), adipogenic (LPL, PLIN1, PPAR-γ), and osteogenic (OCN, OSX, RUNX2) gene marker expression levels also were similar between both groups. <h3>Conclusions</h3> No difference was observed between rongeur biopsy and motorized shaver harvest methods regarding SDMSC yield and cell characteristics. <h3>Clinical Relevance</h3> The current study shows that both rongeur and motorized shaver harvest are safe and effective methods for obtaining SDMSCs. Motorized shaver harvest results in higher volume of tissue acquisition per time, thereby leading to higher number of SDMSCs which may be useful during clinical application.

Three-dimensional (3D) hydrogel serves as a platform to identify potential markers of chondrocyte dedifferentiation by combining RNA sequencing

Dedifferentiation of chondrocyte greatly restricts its function and application, however, it is poorly understood except a small number of canonical markers. The non-cell-adhesive property endows polysaccharide hydrogel with the ability to maintain chondrocyte phenotype, which can serve as a platform to identify new molecular markers and therapeutic targets of chondrocyte dedifferentiation. In this study, the high-throughput RNA sequencing (RNA-seq) was first performed on articular chondrocytes at primary (P0) and passage 1 (P1) stages to explore the global alteration of gene expression along with chondrocyte dedifferentiation. Significantly, several potential marker genes, such as PFKFB3, KDM6B, had been identified via comparatively analyzing their expression in P0 and P1 chondrocytes as well as in 3D constructs (i.e. chondrocyte-laden alginate hydrogel and HA-MA hydrogel) at both mRNA and protein level. Besides, the changes in cellular morphology and enriched pathway of differentially expressed genes during chondrocyte dedifferentiation was studied in detail. This study developed the use of hydrogel as a platform to investigate chondrocyte dedifferentiation; the results provided new molecular markers and potential therapeutic targets of chondrocyte dedifferentiation.

C-Casitas b-Lineage Lymphoma Downregulation Improves the Ability of Long-term Cultured Mesenchymal Stem Cells for Promoting Angiogenesis and Diabetic Wound Healing

The chronic wound induced by diabetes has poor efficacy and could lead to amputation. The repair function of mesenchymal stem cells (MSCs) impaired after long-term culture in vitro. Studies have shown that the proto-oncogene c-Casitas b-lineage lymphoma (c-Cbl) can regulate receptor- and non-receptor tyrosine kinase, which was also involved in the angiogenesis process. This study aimed to explore the regulative effect of c-Cbl on the proangiogenic functions of long-term cultured MSCs and evaluate its pro-healing effect on diabetic wounds. In this study, the c-Cbl level was downregulated by locked nucleic acid–modified antisense oligonucleotide gapmers (LNA Gapmers). We detected the effect of c-Cbl downregulation on long-term cultured MSCs in terms of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signal, cellular proliferation, senescence, migration, and angiogenic factors paracrine activity in vitro. In vivo, we observed the pro-healing effect of long-term cultured MSCs, with or without c-Cbl downregulation, on the diabetic wound. We found that the phosphorylation level of c-Cbl increased and that of Akt decreased in passage 10 (P10) MSCs compared with passage 3 (P3) MSCs (P < 0.05). Additionally, the proliferation, paracrine, and migration capacity of P10 MSCs decreased significantly, accompanied by the increase of cellular senescence (P < 0.05). However, these functions, including PI3K/Akt activity of P10 MSCs, have been improved by c-Cbl downregulation (P < 0.05). Compared with P10 MSCs treatment, treatment with c-Cbl downregulated P10 MSCs accelerated diabetic wound healing, as defined by a more rapid wound closure (P < 0.05), more neovascularization (P < 0.05), and higher scores of wound histological assessment (P < 0.05) in a diabetic rat model. Our findings suggested that c-Cbl downregulation could attenuate the impairment of proangiogenic functions in MSCs induced by long-term culture in vitro and improve the effect of long-term cultured MSCs in promoting diabetic wound healing.

Cellular Properties and Expression of Pluripotent Markers in Human Dental Pulp Stem Cells Cultured in Serum-Free Medium

Introduction: The standard isolation and expansion of human Dental Pulp Stem Cells (DPSCs) under invitro conditions normally involve the usage of Fetal Bovine Serum (FBS). However, its animal-origin poses possible concerns for clinically relevant procedures. This critical issue compels the use of Xenogeneic-Free (XF) or human-origin alternatives to FBS for culture expansion and differentiation of DPSCs to determine the usefulness for translating into therapeutic clinical applications. Aim: To evaluate the cellular characteristics and expression of pluripotent markers in DPSCs cultured using Serum-Containing Medium (SCM-DPSCs) and Serum-Free Medium (SFM-DPSCs). Materials and Methods: This in-vitro descriptive study was conducted at NITTE (Deemed to be University), Mangaluru, Karnataka, India, from June 2019 to August 2020. DPSCs were isolated from impacted third molars. The culture expanded DPSCs in serum-containing and serum-free media were analysed on their morphology, viability, proliferation rate, Population Doubling Time (PDT), Alkaline Phosphatase (ALP) activity, cell surface markers expression, osteogenic and adipogenic potential, and the relative expression of selected pluripotent genes. Results: The primary culture of DPSCs established in SCM and SFM showed spindle shaped fibroblastic morphology with &gt;80% viability from passage 1 (P1) to P4. A significant (p-value&lt;0.05) difference in the proliferation rates in terms of cell numbers between SCM-DPSCs and SFM-DPSCs was observed (day 6: 3×105 vs 0.8×105; day 9: 5.8×105 vs 1.27×105; day 12: 7.8×105vs 1.56×105, respectively). The average PDT values recorded in SCM- and SFM-DPSCs were 44.33 hours and 58.41 hours, respectively. A slightly higher expression of ALP activity was observed in SCM-DPSCs than in SFM-DPSCs. Flow cytometry analysis showed that both DPSCs were positive for CD29, CD73, CD90, and negative for CD34 and CD45. The expression of OCT4 and NANOG was relatively higher in SCM-DPSCs compared to SFM-DPSCs. Further, SCM-DPSCs showed the higher levels of SOX2 and SSEA4, but did not exhibit any significant differences in their expression levels. Conclusion: The results showed that DPSCs in FBS displayed better growth kinetics and stemness markers expression along with more propensities towards lineage differentiation. SFM can be used to establish and expand DPSCs with characteristics of multipotent stem cells, but needs further research for its optimisation.

Human aortic valve interstitial cells obtained from patients with aortic valve stenosis are vascular endothelial growth factor receptor 2 positive and contribute to ectopic calcification

Since aortic valve stenosis (AVS) is the most frequent and serious valvular heart disease in the elderly, and is accompanied by irreversible valve calcification, medicinal prevention of AVS is important. Although we recently demonstrated that human aortic valve interstitial cells (HAVICs) obtained from patients with AVS were highly sensitive to ectopic calcification stimulation, the cell types contributing to calcification are unknown. We aimed to immunocytochemically characterize HAVICs and identify their contribution to valve calcification. HAVICs were isolated from patients with AVS and cultured on non-coated dishes. Immunocytochemical features and HAVIC differentiation were analyzed in passage 1 (P1). The immunohistochemical features of the calcified aortic valve were analyzed. Most cultured P1 HAVICs were CD73-, CD90-, and CD105-positive, and CD45-and CD34-negative. HAVICs were vascular endothelial growth factor receptor 2 (VEGFR2)-positive; however, approximately half were α-smooth muscle actin (SMA)-positive, colonized, and easily differentiated into osteoblastic cells. Calcified aortic valve immunohistochemistry showed that all cells were positive for VEGFR2 and partly α-SMA. Further, VEGFR2-positive cells were more sensitive to tumor necrosis factor-α-induced ectopic calcification with or without α-SMA positivity. We conclude that HAVICs obtained from patients with AVS are VEGFR2-positive undifferentiated mesenchymal cells and may contribute to aortic valve ectopic calcification.

Late Passage Cultivation Induces Aged Astrocyte Phenotypes in Rat Primary Cultured Cells.

Astrocytes play various important roles such as maintaining brain homeostasis, supporting neurons, and secreting inflammatory mediators to protect the brain cells. In aged subjects, astrocytes show diversely changed phenotypes and dysfunctions. But, the study of aged astrocytes or astrocytes from aged subjects is not yet sufficient to provide a comprehensive understanding of their important processes in the regulation of brain function. In this study, we induced an in vitro aged astrocyte model through late passage cultivation of rat primary cultured astrocytes. Astrocytes were cultured until passage 7 (P7) as late passage astrocytes and compared with passage 1 (P1) astrocytes as early passage astrocytes to confirm the differences in phenotypes and the effects of serial passage. In this study, we confirmed the morphological, molecular, and functional changes of late passage astrocytes showing aging phenotypes through SA-β-gal staining and measurement of nuclear size. We also observed a reduced expression of inflammatory mediators including IL-1β, IL-6, TNFα, iNOS, and COX2, as well as dysregulation of wound-healing, phagocytosis, and mitochondrial functions such as mitochondrial membrane potential and mitochondrial oxygen consumption rate. Culture-conditioned media obtained from P1 astrocytes promoted neurite outgrowth in immature primary cultures of rat cortices, which is significantly reduced when we treated the immature neurons with the culture media obtained from P7 astrocytes. These results suggest that late passage astrocytes show senescent astrocyte phenotypes with functional defects, which makes it a suitable model for the study of the role of astrocyte senescence on the modulation of normal and pathological brain aging.

Reversibility of hAT-MSCs phenotypic and metabolic changes after exposure to and withdrawal from HCC-conditioned medium through regulation of the ROS/MAPK/HIF-1\u03b1 signaling pathway

BackgroundMesenchymal stem cells (MSCs) play an important role in tumor progression; concomitantly, MSCs also undergo profound changes in the tumor microenvironment (TME). These changes can directly impact the application and efficacy of MSC-based anti-tumor therapy. However, few studies have focused on the regulation of MSC fate in TME, which will limit the progress of MSC-based anti-tumor therapy. Herein, we investigated the effects of conditioned medium from human hepatocellular carcinoma cells (HCC-CM) on the phenotype and glucose metabolism of human adipose tissue-derived MSCs (hAT-MSCs).MethodsThe passage 2 (P2) to passage 3 (P3) hAT-MSCs were exposed to conditioned medium from Hep3B, Huh7 and HCCLM3 cells for 4–8 weeks in vitro. Then, immunofluorescent, CCK-8 assay, EdU assay, Transwell assay, and flow cytometry were used to assess the alterations in cell phenotype in terms of cell morphology, secretory profiles, proliferation, migration, invasion, cell cycle, and apoptosis. In addition, glucose metabolism was evaluated by related kits. Next, the treated hAT-MSCs were subjected to withdrawal from HCC-CM for 2–4 weeks, and alterations in phenotype and glucose metabolism were reevaluated. Finally, the molecular mechanism was clarified by Western blotting.ResultsThe results revealed that after exposure to HCC-CM, hAT-MSCs developed a stellate-shaped morphology. In association with cytoskeleton remodeling, hAT-MSCs showed enhanced capacities for migration and invasion, while cell proliferation was inhibited by regulating the cell cycle by downregulating cyclins and cyclin-dependent kinases and activating the mitochondrial apoptosis pathway. In terms of glucose metabolism, our results showed mitochondrial dysfunction and elevated glycolysis of hAT-MSCs. However, interestingly, when the treated hAT-MSCs were subjected to withdrawal from HCC-CM, the alterations in phenotype and glucose metabolism could be reversed, but secretory phenotype and tumor-promoting properties appear to be permanent. Further studies showed that these changes in hAT-MSCs may be regulated by the ROS/MAPK/HIF-1α signaling pathway.ConclusionTaken together, the effects of long-term HCC-CM treatment on phenotype and glucose metabolism in hAT-MSCs are modest and largely reversible after withdrawal, but HCC-CM endow hAT-MSCs with permanent secretory phenotype and tumor-promoting properties. This is the first report on the reversal of phenotype and glucose metabolism in tumor-associated MSCs (TA-MSCs), it is anticipated that new insights into TA-MSCs will lead to the development of novel strategies for MSC-based anti-tumor therapy.

Baghdadite Ceramics Prevent Senescence in Human Osteoblasts and Promote Bone Regeneration in Aged Rats.

Bone fractures and critical-sized bone defects present significant health threats for the elderly who have limited capacity for regeneration due to the presence of functionally compromised senescent cells. A wide range of synthetic materials has been developed to promote the regeneration of critical-sized bone defects, but it is largely unknown if a synthetic biomaterial (scaffold) can modulate cellular senescence and improve bone regeneration in aged scenarios. The current study investigates the interaction of Baghdadite (Ca3ZrSi2O9) ceramic scaffolds with senescent human primary osteoblast-like cells (HOBs) and its bone regeneration capacity in aged rats. A senescent HOB model was established by repeatedly passaging HOBs till passage 7 (P7). Compared to the clinically used hydroxyapatite/tricalcium phosphate (HA/TCP), Baghdadite prevented senescence induction in P7 HOBs and markedly negated the paracrine effect of P7 HOB secretomes that mediated the up-regulations of cellular senescence-associated gene expression levels in P2 HOBs. We further demonstrated that conditioned media extracted from Baghdadite corrected the dysfunctional mitochondria in P7 HOBs. In vivo, the bone regeneration capacity was enhanced when 3D printed Baghdadite scaffolds were implanted in a calvaria critical-sized bone defect model in both young and aged rats compared to HA/TCP scaffolds, but a better effect was observed in aged rats than in young rats. This study suggests that Baghdadite ceramic represents a novel and promising biomaterial approach to promote bone regeneration capacity in the elderly by providing an anti-senescent microenvironment.

Growth and proliferation of caprine bone marrow mesenchymal stem cells on different culture media

The growth and proliferation of mesenchymal stem cells are very sensitive in in vitro and a number of factors like media play a significant role in that context. In this study we assessed effect of different media on growth and proliferation of bone marrow derived mesenchymal stem cells (BMMSCs). The BMMSCs were isolated from caprine bone marrow and were subjected to magnetic activated cell sorting against CD90+, CD105+, CD271+and CD34− along with FC blocker. After characterisation, 2 × 104 cells were seeded in 12 well culture plates in four different media viz. MesenCult, MesenPRO, StemPro and complete DMEM (15 % FBS) to study their growth kinetic for 6 days from passage 0 (P0) to passage 3 (P3). The population doubling time (PDT) was derived from growth curve using logarithmic formula. The results showed that the BMMSCs growth and proliferation was highest in MesenCult media in P0 which varied significantly (p < 0.05) from rest of media and from P1 to P3, it was MesenPRO which yielded maximum cells (p < 0.05). The PDT was also in line with growth curve findings. In conclusion, the MesenPRO media had higher growth and proliferation rate from P1 to P3 although MesenCult had higher cell numbers in P0. In conclusion, the use of MesenPRO media could be a better option than conventional media when mesenchymal stem cells are used in clinical applications and other therapeutic purposes taking consideration to its higher growth and proliferation rate. And MesenCult would be a great option to harvest MSCs from P0.

Ceramide accumulation accelerates nucleus pulposus cells degradation by p38MAPK activation.

Ceramide is a lipid molecule that regulates life activities such as cell differentiation, proliferation, apoptosis, and aging. However, whether ceramide plays a role in the intervertebral disc degeneration (IDD) is not clear. The aim of this study is to explore the effect of ceramide during the nucleus pulposus (NP) cells degeneration. We used human NP cells and passaged them until the fourth generation to analyze the content of ceramide. Cell-permeable C6-ceramide was used to upregulate ceramide expression, and myriocin was used to inhibit the accumulation of ceramide. To understand the relation between p38MAPK and ceramide, SB203580 was used to inhibit the activation of p38MAPK. We tested the viability of NP cells by the detection of collagen II and p16 expression, the proliferation, and the apoptosis of NP cells. Ceramide content was increased in NP cells from passage 1 (P1) to P4. The upregulation of ceramide accelerated the P1 NP cell degeneration by the reduction of collagen II production and proliferative cells population, increased p16 expression, and apoptotic cells population. However, the suppression of ceramide delayed the degeneration of P4 NP cells in the previous aspects. The accumulation of ceramide activated the phosphorylation of p38MAPK, and the inhibition of p38MAPK activation also alleviated the C6-ceramide-induced NP cell degeneration. Ceramide accumulates during NP cell degradation, and the upregulated ceramide contributes to the NP cells degeneration by p38MAPK activation.

Bone Marrow-Derived Mesenchymal Stem Cells Isolated from Patients with Cirrhosis and Healthy Volunteers Show Comparable Characteristics.

Background and ObjectivesAutologous or allogeneic bone marrow-derived mesenchymal stem cells (BMSCs) have been applied in clinical trials to treat liver disease. However, only a few studies are comparing the characteristics of autologous MSCs from patients and allogeneic MSCs from normal subjects.Methods and ResultsWe compared the characteristics of BMSCs (BCs and BPs, respectively) isolated from six healthy volunteers and six patients with cirrhosis. In passage 3 (P3), senescent population and expression of p53 and p21 were slightly higher in BPs, but the average population doubling time for P3–P5 in BPs was approximately 65.3±11.1 h, which is 18.4 h shorter than that in BCs (83.7±9.2 h). No difference was observed in the expression of CD73, CD90, or CD105 between BCs and BPs. Adipogenic differentiation slightly increased in BCs, but the expression levels of leptin, peroxisome proliferator-activated receptor γ, and CCAAT-enhancer-binding protein α did not vary between differentiated BCs and BPs. While ATP and reactive oxygen species levels were slightly lower in BPs, mitochondrial membrane potential, oxygen consumption rate, and expression of mitochondria-related genes such as cytochrome c oxidase 1 were not significantly different between BCs and BPs.ConclusionsTaken together, there are marginal differences in the proliferation, differentiation, and mitochondrial activities of BCs and BPs, but both BMSCs from patients with cirrhosis and healthy volunteers show comparable characteristics.

Hepatocyte growth factor (HGF) and stem cell factor (SCF) maintained the stemness of human bone marrow mesenchymal stem cells (hBMSCs) during long-term expansion by preserving mitochondrial function via the PI3K/AKT, ERK1/2, and STAT3 signaling pathways

BackgroundMesenchymal stem cells (MSCs) have a limited self-renewal ability, impaired multi-differentiation potential, and undetermined cell senescence during in vitro series expansion. To address this concern, we investigated the effects of the microenvironment provided by stem cells from human exfoliated deciduous teeth (SHED) in maintaining the stemness of human bone marrow mesenchymal stem cells (hBMSCs) and identified the key factors and possible mechanisms responsible for maintaining the stemness of MSCs during long-term expansion in vitro.MethodsThe passage 3 (P3) to passage 8 (P8) hBMSCs were cultured in the conditioned medium from SHED (SHED-CM). The percentage of senescent cells was evaluated by β-galactosidase staining. In addition, the osteogenic differentiation potential was analyzed by reverse transcription quantitative PCR (RT-qPCR), Western blot, alizarin red, and alkaline phosphatase (ALP) staining. Furthermore, RT-qPCR results identified hepatocyte growth factor (HGF) and stem cell factor (SCF) as key factors. Thus, the effects of HGF and SCF on mitochondrial function were assessed by measuring the ROS and mitochondrial membrane potential levels. Finally, selected mitochondrial-related proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways were investigated to determine the effects of HGF and SCF in preserving the mitochondrial function of hBMSCs during long-term expansion.ResultsSHED-CM had significantly enhanced the cell proliferation, reduced the senescent cells, and maintained the osteogenesis and pro-angiogenic capacity in P8 hBMSCs during long-term expansion. In addition, hBMSCs treated with 100 ng/ml HGF and 10 ng/ml SCF had reduced ROS levels and preserved mitochondrial membrane potential compared with P8 hBMSCs during long-term expansion. Furthermore, HGF and SCF upregulated the expression of mitochondrial-related proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways, possibly contributing to the maintenance of hBMSCs stemness by preserving mitochondrial function.ConclusionBoth HGF and SCF are key factors in maintaining the stemness of hBMSCs by preserving mitochondrial function through the expression of proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways. This study provides new insights into the anti-senescence capability of HGF and SCF, as well as new evidence for their potential application in optimizing the long-term culture of MSCs.

Establishing metastatic patient-derived xenograft model for colorectal cancer.

Patient-derived xenograft model is a powerful and promising tool for drug discovery and cancer biology studies. The application of previous metastatic colorectal cancer models has been greatly limited by its low success rate and long time to develop metastasis. Therefore, in this study, we aim to describe an optimized protocol for faster establishment of colorectal cancer metastatic patient-derived xenograft mouse models. Smaller micro tissues (˂150μm in diameter) mixed with Matrigel were engrafted subcutaneously into NSG mice to generate the passage 1 (P1) patient-derived xenograft. The micro tumours from P1 patient-derived xenograft were then excised and orthotopically xenografted into another batch of NSG mice to generate a metastatic colorectal cancer patient-derived xenograft, P2. Haematoxylin and eosin and immunohistochemistry staining were performed to compare the characters between patient-derived xenograft tumours and primary tumours. About 16 out of 18 P1 xenograft models successfully grew a tumour for 50.8±5.1days (success rate 89.9%). Six out of eight P1 xenograft models originating from metastatic patients successfully grew tumours in the colon and metastasized to liver or lung in the NSG recipients for 60.9±4.5days (success rate 75%). Histological examination of both P1 and P2 xenografts closely resembled the histological architecture of the original patients' tumours. Immunohistochemical analysis revealed similar biomarker expression levels, including CDH17, Ki-67, active β-catenin, Ki-67 and α smooth muscle actin when compared with the original patients' tumours. The stromal components that support the growth of patient-derived xenograft tumours were of murine origin. Metastatic patient-derived xenograft mouse model could be established with shorter time and higher success rate. Although the patient-derived xenograft tumours were supported by the stromal cells of murine origin, they retained the dominant characters of the original patient tumours.

Comparison of the rate of dedifferentiation with increasing passages among cell sources for an in vitro model of the blood-brain barrier.

Cell culture-based blood-brain barrier (BBB) models are useful experimental tools for developing central nervous system drugs. Several endothelial cell sources exist for BBB models, including primary cultured brain endothelial cells and immortalized cell lines. Among them, primary cell-based models are considered suitable for the functional analysis of the BBB; however, little is known about the utility of low-passage brain endothelial cells for this purpose. In this study, we investigated the effect of passage on brain endothelial cells from human, mouse and rat brain tissue as BBB models. We established in vitro BBB models using primary brain endothelial cells (Passage 1-Passage 4) from humans, mice, and rats. To analyze the effect of cell type on BBB function, we evaluated transendothelial electrical resistance (TEER) and performed immunofluorescence staining of tight junction proteins. Among the brain endothelial cell models, TEER was highest in the Passage 1 (P1) cell-based BBB model. There was no adequate increase in TEER in other low-passage cultures (P2-P4). A confluent, non-overlapping, uniform monolayer of cells in all P1 cell-based models was visible on immunostaining of tight junction proteins, whereas it was weak or undetectable in more passaged cultures. Increasing passages cultured of brain endothelial cells did not exhibit restrictive BBB function regardless of the cell source and despite culturing with pericytes and astrocytes. Among the tested culture models, only the lowest cultured cell-based models are suitable for functional analysis of the BBB.

Isolation, culture, and induced multiple differentiation of Mongolian sheep adipose-derived mesenchymal stem cells

ABSTRACT Adipose-derived mesenchymal stem cells (ADSC) are adult pluripotent cells and important resources for cell-based therapies of animals. There are presently different kinds of somatic cells used as donor cells for clone successfully. However, studies on somatic cell nuclear transplantation (SCNT) using ADSC as donor cells from Mongolian sheep have not been reported up to now. This study tested optimal methods of isolating, purifying, and proliferating Mongolian sheep ADSC, and determine their multiple differentiation potentiality. Adipose tissue was removed from approximately 2-year-old sheep and ADSC were harvested by pancreatic enzyme decomposition and adherent culture method. The growth curves of the Passages 1, 5, and 10 cultures were plotted and the exponential growth was determined as a population doubling time of 34.1 h. The expression of OCT4, SOX2, and NANOG genes were increased at Passage 3 (P3) as seen by reverse transcription polymerase chain reaction (RT-PCR) analysis. ADSC from Passage 3 were induced to undergo neurogenesis and form cardiomyocytes and pancreatic islet-like cells under inductive environments in vitro. The differentiation properties of cardiomyocytes and islet-like cells were confirmed by histological staining with toluidine blue, periodic acid-Schiff, and dithizone. The expression of specific genes in these cells were also detected by RT-PCR. Our study results confirm that isolated cells were indeed ADSC and may provide valuable materials for somatic cell clone and transgenic research.

Reproducible Derivation and Expansion of Corneal Mesenchymal Stromal Cells for Therapeutic Applications.

PurposeA reproducible protocol for the production of corneal mesenchymal stem/stromal cells (cMSCs) is necessary for potential clinical applications. We aimed to describe successful generation and expansion of cMSCs using an explant method.MethodsCorneoscleral rims of human cadaveric eyes were divided into four pieces and used as explants to allow outgrowth of cMSCs (passage 0, or P0). The cells were subcultured at a 1:10 ratio until passage 5 (P5). The characteristics as well as therapeutic effects of expanded cMSCs were evaluated both in vitro, using a scratch assay, and in vivo using epithelial debridement and chemical injury mouse models.ResultsAll explants demonstrated outgrowth of cells by 7 days. Although the initial outgrowth included mixed mesenchymal and epithelial cells, by P1 only cMSCs remained. By subculturing each flask at a ratio of 1:10, the potential yield from each cornea was approximately 12 to 16 × 1010 P5 cells. P5 cMSCs demonstrated the cell surface markers of MSCs. The secretome of P5 cMSCs induced faster closure of wounds in an in vitro scratch assay. Subconjunctival injection of P5 cMSCs in mouse models of mechanical corneal epithelial debridement or ethanol injury led to significantly faster wound healing and decreased inflammation, relative to control.ConclusionscMSCs can be reproducibly derived from human cadaveric corneas using an explant method and expanded with preservation of characteristics and corneal wound healing effects.Translational RelevanceThe results of our study showed that cMSCs produced using this scheme can be potentially used for clinical applications.

NMR-based metabonomic analysis of HUVEC cells during replicative senescence.

Cellular senescence is a physiological process reacting to stimuli, in which cells enter a state of irreversible growth arrest in response to adverse consequences associated with metabolic disorders. Molecular mechanisms underlying the progression of cellular senescence remain unclear. Here, we established a replicative senescence model of human umbilical vein endothelial cells (HUVEC) from passage 3 (P3) to 18 (P18), and performed biochemical characterizations and NMR-based metabolomic analyses. The cellular senescence degree advanced as the cells were sequentially passaged in vitro, and cellular metabolic profiles were gradually altered. Totally, 8, 16, 21 and 19 significant metabolites were primarily changed in the P6, P10, P14 and P18 cells compared with the P3 cells, respectively. These metabolites were mainly involved in 14 significantly altered metabolic pathways. Furthermore, we observed taurine retarded oxidative damage resulting from senescence. In the case of energy deficiency, HUVECs metabolized neutral amino acids to replenish energy, thus increased glutamine, aspartate and asparagine at the early stages of cellular senescence but decreased them at the later stages. Our results indicate that cellular replicative senescence is closely associated with promoted oxidative stress, impaired energy metabolism and blocked protein synthesis. This work may provide mechanistic understanding of the progression of cellular senescence.

Gene expression profile of immunoregulatory cytokines secreted from bone marrow and adipose derived human mesenchymal stem cells in early and late passages.

Mesenchymal Stem Cells (MSCs) have therapeutic potential in a variety of diseases; however, the safety and efficacy of their use remain ambiguous. Clinical applications of MSCs are under intensive investigation due to their immunomodulatory features and lack of immune reactivity. Therefore, having a clear perspective on the exact mechanisms underlying the regulation of cytokine secretion in different microenvironments seems crucially important.In the current study, samples from human bone marrow and adipose were collected, and peripheral blood mononuclear cells (PBMCs) were isolated and cultured in conventional medium. After MSC expansion, the cells from passage 3 (P3) and passage 9 (P9) were utilized to identify MSC cell surface markers and their differentiation capacity. The P3, P5, P7, and P9 cells were used for RNA extraction to qualify the expression of the main immunomodulatory cytokines IDO, VCAM-1, TGF-β, IL-6, IL-10, and PGE2 at mRNA levels. The results indicate that VCAM-1 expression in the subcultures was reduced in bone marrow-derived MSCs. After an increase in P5, P7, and P9, IL-6 expression was reduced. In adipose-derived MSCs, the mRNA levels of IL-10 in higher passages were decreased compared with P3; other studied cytokines had no significant changes in their expression levels in either bone marrow or adipose-derived MSCs. Based on these results, it can be concluded that a suitable source for MSCs in cell therapy with stable expression of main cytokines, even in higher subcultures, appears to be adipose-derived MSCs with the exception of IL-10 secretion.