首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.

Background

For regenerative therapy using induced pluripotent stem cell (iPSC) technology, cell type of origin to be reprogrammed should be chosen based on accessibility and reprogramming efficiency. Some studies report that iPSCs exhibited a preference for differentiation into their original cell lineages, while others did not. Therefore, the type of cell which is most appropriate as a source for iPSCs needs to be clarified.

Methodology/Principal Findings

Genetically matched human iPSCs from different origins were generated using bone marrow stromal cells (BMSCs) and dermal fibroblasts (DFs) of the same donor, and global gene expression profile, DNA methylation status, and differentiation properties into the chondrogenic and osteogenic lineage of each clone were analyzed. Although genome-wide profiling of DNA methylation suggested tissue memory in iPSCs, genes expressed differentially in BMSCs and DFs were equally silenced in our bona fide iPSCs. After cell-autonomous and induced differentiation, each iPSC clone exhibited various differentiation properties, which did not correlate with cell-of-origin.

Conclusions/Significance

The reprogramming process may remove the difference between DFs and BMSCs at least for chondrogenic and osteogenic differentiation. Qualified and genetically matched human iPSC clone sets established in this study are valuable resources for further basic study of clonal differences.  相似文献   

2.

Background

Spinal cord injury (SCI) deteriorates various physical functions, in particular, bladder problems occur as a result of damage to the spinal cord. Stem cell therapy for SCI has been focused as the new strategy to treat the injuries and to restore the lost functions. The oral mucosa cells are considered as the stem cells-like progenitor cells. In the present study, we investigated the effects of oral mucosa stem cells on the SCI-induced neurogenic bladder in relation with apoptotic neuronal cell death and cell proliferation.

Results

The contraction pressure and the contraction time in the urinary bladder were increased after induction of SCI, in contrast, transplantation of the oral mucosa stem cells decreased the contraction pressure and the contraction time in the SCI-induced rats. Induction of SCI initiated apoptosis in the spinal cord tissues, whereas treatment with the oral mucosa stem cells suppressed the SCI-induced apoptosis. Disrupted spinal cord by SCI was improved by transplantation of the oral mucosa stem cells, and new tissues were increased around the damaged tissues. In addition, transplantation of the oral mucosa stem cells suppressed SCI-induced neuronal activation in the voiding centers.

Conclusions

Transplantation of oral mucosa stem cells ameliorates the SCI-induced neurogenic bladder symptoms by inhibiting apoptosis and by enhancing cell proliferation. As the results, SCI-induced neuronal activation in the neuronal voiding centers was suppressed, showing the normalization of voiding function.  相似文献   

3.

Background

The aim of this paper is to study the function of allogeneic and autologous NK cells against Dental Pulp Stem Cells (DPSCs) and Mesenchymal Stem Cells (MSCs) and to determine the function of NK cells in a three way interaction with monocytes and stem cells.

Methodology/Principal Findings

We demonstrate here that freshly isolated untreated or IL-2 treated NK cells are potent inducers of cell death in DPSCs and MSCs, and that anti-CD16 antibody which induces functional split anergy and apoptosis in NK cells inhibits NK cell mediated lysis of DPSCs and MSCs. Monocytes co-cultured with either DPSCs or MSCs decrease lysis of stem cells by untreated or IL-2 treated NK cells. Monocytes also prevent NK cell apoptosis thereby raising the overall survival and function of NK cells, DPSCs or MSCs. Both total population of monocytes and those depleted of CD16+ subsets were able to prevent NK cell mediated lysis of MSCs and DPSCs, and to trigger an increased secretion of IFN-γ by IL-2 treated NK cells. Protection of stem cells from NK cell mediated lysis was also seen when monocytes were sorted out from stem cells before they were added to NK cells. However, this effect was not specific to monocytes since the addition of T and B cells to stem cells also protected stem cells from NK cell mediated lysis. NK cells were found to lyse monocytes, as well as T and B cells.

Conclusion/Significance

By increasing the release of IFN-γ and decreasing the cytotoxic function of NK cells monocytes are able to shield stem cells from killing by the NK cells, resulting in an increased protection and differentiation of stem cells. More importantly studies reported in this paper indicate that anti-CD16 antibody can be used to prevent NK cell induced rejection of stem cells.  相似文献   

4.
PP Wang  DY Xie  XJ Liang  L Peng  GL Zhang  YN Ye  C Xie  ZL Gao 《PloS one》2012,7(8):e43408

Aims

Bone marrow-derived mesenchymal stem cells (BMSCs) can reduce liver fibrosis. Apart from the paracrine mechanism by which the antifibrotic effects of BMSCs inhibit activated hepatic stellate cells (HSCs), the effects of direct interplay and juxtacrine signaling between the two cell types are poorly understood. The purpose of this study was to explore the underlying mechanisms by which BMSCs modulate the function of activated HSCs.

Methods

We used BMSCs directly and indirectly co-culture system with HSCs to evaluate the anti-fibrosis effect of BMSCs. Cell proliferation and activation were examined in the presence of BMSCs and HGF. c-met was knockdown in HSCs to evaluate the effect of HGF secreted by BMSCs. The TLR4 and Myeloid differentiation primary response gene 88(MyD88) mRNA levels and the NF-kB pathway activation were determined by real-time PCR and western blotting analyses. The effect of BMSCs on HSCs activation was investigated in vitro in either MyD88 silencing or overexpression in HSCs. Liver fibrosis in rats fed CCl4 with and without BMSCs supplementation was compared. Histopathological examinations and serum biochemical tests were compared between the two groups.

Results

BMSCs remarkably inhibited the proliferation and activation of HSCs by interfering with LPS-TLR4 pathway through a cell–cell contact mode that was partially mediated by HGF secretion. The NF-kB pathway is involved in HSCs activation inhibition by BMSCs. MyD88 over expression reduced the BMSC inhibition of NF-kB luciferase activation. BMSCs protected liver fibrosis in vivo.

Conclusion

BMSCs modulate HSCs in vitro via TLR4/MyD88/NF-kB signaling pathway through cell–cell contact and secreting HGF. BMSCs have therapeutic effects on cirrhosis rats. Our results provide new insights into the treatment of hepatic fibrosis with BMSCs.  相似文献   

5.

Objective

To investigate the effect of intraventricular injection of human dental pulp stem cells (DPSCs) on hypoxic-ischemic brain damage (HIBD) in neonatal rats.

Methods

Thirty-six neonatal rats (postnatal day 7) were assigned to control, HIBD, or HIBD+DPSC groups (n = 12 each group). For induction of HIBD, rats underwent left carotid artery ligation and were exposed to 8% to 10% oxygen for 2 h. Hoechst 33324-labeled human DPSCs were injected into the left lateral ventricle 3 days after HIBD. Behavioral assays were performed to assess hypoxic-ischemic encephalopathy (HIE), and on postnatal day 45, DPSC survival was assessed and expression of neural and glial markers was evaluated by immunohistochemistry and Western blot.

Results

The HIBD group showed significant deficiencies compared to control on T-maze, radial water maze, and postural reflex tests, and the HIBD+DPSC group showed significant improvement on all behavioral tests. On postnatal day 45, Hoechst 33324-labeled DPSC nuclei were visible in the injected region and left cortex. Subsets of DPSCs showed immunostaining for neuronal (neuron-specific enolase [NSE], Nestin) and glial markers (glial fibrillary acidic protein [GFAP], O4). Significantly decreased staining/expression for NSE, GFAP, and O4 was found in the HBID group compared to control, and this was significantly increased in the HBID+DPSC group.

Conclusion

Intraventricular injection of human DPSCs improves HIBD in neonatal rats.  相似文献   

6.

Objective

The effect of Sox9 on the differentiation of bone marrow mesenchymal stem cells (BMSCs) to nucleus pulposus (NP)-like (chondrocyte-like) cells in vitro has been demonstrated. The objective of this study is to investigate the efficacy and feasibility of Sox9-transduced BMSCs to repair the degenerated intervertebral disc in a rabbit model.

Materials and Methods

Fifty skeletally mature New Zealand white rabbits were used. In the treatment groups, NP tissue was aspirated from the L2-L3, L3-L4, and L4-L5 discs in accordance with a previously validated rabbit model of intervertebral disc degeneration and then treated with thermogelling chitosan (C/Gp), GFP-transduced autologous BMSCs with C/Gp or Sox9-transduced autologous BMSCs with C/Gp. The role of Sox9 in the chondrogenic differentiation of BMSCs embedded in C/Gp gels in vitro and the repair effect of Sox9-transduced BMSCs on degenerated discs were evaluated by real-time PCR, conventional and quantitative MRI, macroscopic appearance, histology and immunohistochemistry.

Results

Sox9 could induce the chondrogenic differentiation of BMSCs in C/Gp gels and BMSCs could survive in vivo for at least 12 weeks. A higher T2-weighted signal intensity and T2 value, better preserved NP structure and greater amount of extracellular matrix were observed in discs treated with Sox9-transduced BMSCs compared with those without transduction.

Conclusion

Sox9 gene transfer could significantly enhance the repair effect of BMSCs on the degenerated discs.  相似文献   

7.

Aims

Cigarette smoking is one of the high risk factors of adult chronic periodontitis and nicotine is the well established toxic substance in cigarette. However, the mechanism of nicotine induced periodontitis is still unknown. Here we studied whether nicotine impaired the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) through activating α7 nicotinic acetylcholine receptor (α7 nAChR).

Methods

hPDLSCs with multi differentiation potential and surface makers for mesenchymal stem cells were harvested by limiting dilution technique. The level of mineralized nodule formation was assessed by alizarin red S staining. Expression level of ostegenic related genes and proteins were detected by real-time PCR and western blot analysis. The expression of α7 nAChR and its downstream signaling pathway were examined by western blot. The role of the receptor and related signaling pathway in nicotine impairing the osteogenic potential of hPDLSCs were also studied in different levels.

Results

Nicotine deteriorated the ostegenic differentiation of hPDLSCs in a dose dependent manner. Activation of α7 nAChR by nicotine treatment activated wnt/β-catenin signaling pathway, leading to osteogenic deficiency of hPDLSCs. Blockage of α7 nAChR and wnt pathway inhibitor treatment rescued nicotine induced osteogenic differentiation deficiency.

Conclusions

These data suggested that nicotine activated α7 nAChR expressed on PDLSCs and further activated wnt signaling downstream, thus deteriorating the osteogenic potential of PDLSCs. The impairment of osteogenic differentiation of PDLSCs by nicotine might lead to cigarette smoking related periodontitis.  相似文献   

8.

Background

Human embryonic stem cells (hESC) provide a unique model to study early events in human development. The hESC-derived cells can potentially be used to replace or restore different tissues including neuronal that have been damaged by disease or injury.

Methodology and Principal Findings

The cells of two different hESC lines were converted to neural rosettes using adherent and chemically defined conditions. The progenitor cells were exposed to retinoic acid (RA) or to human recombinant basic fibroblast growth factor (bFGF) in the late phase of the rosette formation. Exposing the progenitor cells to RA suppressed differentiation to rostral forebrain dopamine neural lineage and promoted that of spinal neural tissue including motor neurons. The functional characteristics of these differentiated neuronal precursors under both, rostral (bFGF) and caudalizing (RA) signals were confirmed by patch clamp analysis.

Conclusions/Significance

These findings suggest that our differentiation protocol has the capacity to generate region-specific and electrophysiologically active neurons under in vitro conditions without embryoid body formation, co-culture with stromal cells and without presence of cells of mesodermal or endodermal lineages.  相似文献   

9.

Aims

Periodontal ligament stem cells (PDLSCs) are one of the best candidates for periodontal regeneration. Their function could be impaired in periodontitis microenvironment. Dental follicle cells (DFCs), serving as precursor cells and mesenchymal stem cells, have intimate connection with PDLSCs. However, it is still unknown whether DFCs could provide a favorable microenvironment to improve the proliferation and differentiation capacity of PDLSCs from healthy subjects (HPDLSCs) and patients diagnosed with periodontitis (PPDLSCs).

Methods

HPDLSCs, PPDLSCs and DFCs were harvested and identified using microscopic and flow cytometric analysis. Then, the coculture systems of DFCs/HPDLSCs and DFCs/PPDLSCs were established with 0.4 µm transwell, in which all the detection indexs were obtained from HPDLSCs and PPDLSCs. The expression of stemness-associated genes was detected by real-time PCR, and the proliferation ability was assessed using colony formation and cell cycle assays. The osteogenic differentiation capacity was evaluated by real-time PCR, western blot, ALP activity, Alizarin Red S staining and calcium level analysis, while the adipogenic differentiation capacity was determined by real-time PCR and Oil Red O staining. The cell sheet formation in vitro was observed by HE staining and SEM, and the implantation effect in vivo was evaluated using HE staining and Masson’s trichrome staining.

Results

PPDLSCs had a greater proliferation capability but lower osteogenic and adipogenic potential than HPDLSCs. DFCs enhanced the proliferation and osteogenic/adipogenic differentiation of HPDLSCs and PPDLSCs to different degrees. Moreover, coculture with DFCs increased cell layers and extracellular matrix of HPDLSCs/PPDLSCs cell sheets in vitro and improved periodontal regeneration by HPDLSCs/PPDLSCs in vivo.

Conclusions

Our data suggest that the function of PPDLSCs could be damaged in the periodontitis microenvironment. DFCs appear to enhance the self-renewal and multi-differentiation capacity of both HPDLSCs and PPDLSCs, which indicates that DFCs could provide a beneficial microenvironment for periodontal regeneration using PDLSCs.  相似文献   

10.

Introduction

Glioblastoma is the most common primary malignant brain tumor, and is refractory to surgical resection, radiation, and chemotherapy. Human mesenchymal stem cells (hMSC) may be harvested from bone marrow (BMSC) and adipose (AMSC) tissue. These cells are a promising avenue of investigation for the delivery of adjuvant therapies. Despite extensive research into putative mechanisms for the tumor tropism of MSCs, there remains no direct comparison of the efficacy and specificity of AMSC and BMSC tropism towards glioma.

Methods

Under an IRB-approved protocol, intraoperative human Adipose MSCs (hAMSCs) were established and characterized for cell surface markers of mesenchymal stem cell origin in conjunction with the potential for tri-lineage differentiation (adipogenic, chondrogenic, and osteogenic). Validated experimental hAMSCs were compared to commercially derived hBMSCs (Lonza) and hAMSCs (Invitrogen) for growth responsiveness and glioma tropism in response to glioma conditioned media obtained from primary glioma neurosphere cultures.

Results

Commercial and primary culture AMSCs and commercial BMSCs demonstrated no statistically significant difference in their migration towards glioma conditioned media in vitro. There was statistically significant difference in the proliferation rate of both commercial AMSCs and BMSCs as compared to primary culture AMSCs, suggesting primary cultures have a slower growth rate than commercially available cell lines.

Conclusions

Adipose- and bone marrow-derived mesenchymal stem cells have similar in vitro glioma tropism. Given the well-documented ability to harvest larger numbers of AMSCs under local anesthesia, adipose tissue may provide a more efficient source of MSCs for research and clinical applications, while minimizing patient morbidity during cell harvesting.  相似文献   

11.

Background

To compare the efficacy of the therapy of spinal cord injury with intravenous transplantation of bone marrow mesenchymal stem cells (BMSCs) by Meta-analysis.

Methods

Studies of the BBB scores after intravenous transplantation of BMSCs were searched out from Pubmed, SCI, Cochrane Library, Chinese journal full-text database, China Biology Medicinedisc and Wanfang data-base and analyzed by Review Manager 5.2.5.

Results

Nine randomized controlled animal trials were selected with 235 rats enrolled. The studies are divided to different subgroups by different models of SCI and different time to transplantion. The results of Meta-analysis in different subgroups both indicated that the rats of experimental group (BMSCs group) got better BBB scores than control group at 1, 3 and over 5 weeks after intravenous transplantation of BMSCs with significant differences. The heterogeneity between impacted injury model and oppressed injury model subgroups decreased with the passage of time (I2 = 75.8%, 39.7%, 0%). No heterogeneity was found between 3 d and 7 d subgroups.

Conclusion

The intravenous transplantation of BMSCs is an efficient way to cure spinal cord injury, which can improve the motor function of rats. The therapeutic window is wide.  相似文献   

12.

Background

Matrix metalloproteinases (MMPs) have recently been considered to be involved in the neurogenic response of adult neural stem/progenitor cells. However, there is a lack of information showing direct association between the activation of MMPs and the development of neuronal progenitor cells involving proliferation and/or further differentiation in vulnerable (Cornus Ammoni-CA1) and resistant (dentate gyrus-DG) to ischemic injury areas of the brain hippocampus.

Principal Findings

We showed that dynamics of MMPs activation in the dentate gyrus correlated closely with the rate of proliferation and differentiation of progenitor cells into mature neurons. In contrast, in the damaged CA1 pyramidal cells layer, despite the fact that some proliferating cells exhibited antigen specific characteristic of newborn neuronal cells, these did not attain maturity. This coincides with the low, near control-level, activity of MMPs. The above results are supported by our in vitro study showing that MMP inhibitors interfered with both the proliferation and differentiation of the human neural stem cell line derived from umbilical cord blood (HUCB-NSCs) toward the neuronal lineage.

Conclusion

Taken together, the spatial and temporal profiles of MMPs activity suggest that these proteinases could be an important component in neurogenesis-associated processes in post-ischemic brain hippocampus.  相似文献   

13.
14.
15.

Background

Microsatellites have been used extensively in the field of comparative genomics. By studying microsatellites in coding regions we have a simple model of how genotypic changes undergo selection as they are directly expressed in the phenotype as altered proteins. The simplest of these tandem repeats in coding regions are the tri-nucleotide repeats which produce a repeat of a single amino acid when translated into proteins. Tri-nucleotide repeats are often disease associated, and are also known to be unstable to both expansion and contraction. This makes them sensitive markers for studying proteome evolution, in closely related species.

Results

The evolutionary history of the family of malarial causing parasites Plasmodia is complex because of the life-cycle of the organism, where it interacts with a number of different hosts and goes through a series of tissue specific stages. This study shows that the divergence between the primate and rodent malarial parasites has resulted in a lineage specific change in the simple amino acid repeat distribution that is correlated to A–T content. The paper also shows that this altered use of amino acids in SAARs is consistent with the repeat distributions being under selective pressure.

Conclusions

The study shows that simple amino acid repeat distributions can be used to group related species and to examine their phylogenetic relationships. This study also shows that an outgroup species with a similar A–T content can be distinguished based only on the amino acid usage in repeats, and suggest that this might be a useful feature for proteome clustering. The lineage specific use of amino acids in repeat regions suggests that comparative studies of SAAR distributions between proteomes gives an insight into the mechanisms of expansion and the selective pressures acting on the organism.  相似文献   

16.

Background

Targeted differentiation of stem cells is mainly achieved by the sequential administration of defined growth factors and cytokines, although these approaches are quite artificial, cost-intensive and time-consuming. We now present a simple xenogeneic rat brain co-culture system which supports neuronal differentiation of adult human stem cells under more in vivo-like conditions.

Methods and Findings

This system was applied to well-characterized stem cell populations isolated from human skin, parotid gland and pancreas. In addition to general multi-lineage differentiation potential, these cells tend to differentiate spontaneously into neuronal cell types in vitro and are thus ideal candidates for the introduced co-culture system. Consequently, after two days of co-culture up to 12% of the cells showed neuronal morphology and expressed corresponding markers on the mRNA and protein level. Additionally, growth factors with the ability to induce neuronal differentiation in stem cells could be found in the media supernatants of the co-cultures.

Conclusions

The co-culture system described here is suitable for testing neuronal differentiation capability of numerous types of stem cells. Especially in the case of human cells, it may be of clinical relevance for future cell-based therapeutic applications.  相似文献   

17.

Objective

Bone marrow stromal cells (BMSCs) are heterogeneous and their therapeutic effect is pleiotropic. Multilineage-differentiating stress enduring (Muse) cells are recently identified to comprise several percentages of BMSCs, being able to differentiate into triploblastic lineages including neuronal cells and act as tissue repair cells. This study was aimed to clarify how Muse and non-Muse cells in BMSCs contribute to functional recovery after ischemic stroke.

Methods

Human BMSCs were separated into stage specific embryonic antigen-3-positive Muse cells and -negative non-Muse cells. Immunodeficient mice were subjected to permanent middle cerebral artery occlusion and received transplantation of vehicle, Muse, non-Muse or BMSCs (2.5×104 cells) into the ipsilateral striatum 7 days later.

Results

Motor function recovery in BMSC and non-Muse groups became apparent at 21 days after transplantation, but reached the plateau thereafter. In Muse group, functional recovery was not observed for up to 28 days post-transplantation, but became apparent at 35 days post-transplantation. On immunohistochemistry, only Muse cells were integrated into peri-infarct cortex and differentiate into Tuj-1- and NeuN-expressing cells, while negligible number of BMSCs and non-Muse cells remained in the peri-infarct area at 42 days post-transplantation.

Conclusions

These findings strongly suggest that Muse cells and non-Muse cells may contribute differently to tissue regeneration and functional recovery. Muse cells may be more responsible for replacement of the lost neurons through their integration into the peri-infarct cortex and spontaneous differentiation into neuronal marker-positive cells. Non-Muse cells do not remain in the host brain and may exhibit trophic effects rather than cell replacement.  相似文献   

18.

Background

Transplantation with bone marrow-derived mesenchymal stem cells (BMSCs) improves the survival of neurons and axonal outgrowth after stroke remains undetermined. Here, we investigated whether PI3K/AKT signaling pathway is involved in these therapeutic effects of BMSCs.

Methodology/Principal Findings

(1) BMSCs and cortical neurons were derived from Sprague-Dawley rats. The injured neurons were induced by Oxygen–Glucose Deprivation (OGD), and then were respectively co-cultured for 48 hours with BMSCs at different densities (5×103, 5×105/ml) in transwell co-culture system. The average length of axon and expression of GAP-43 were examined to assess the effect of BMSCs on axonal outgrowth after the damage of neurons induced by OGD. (2) The injured neurons were cultured with a conditioned medium (CM) of BMSCs cultured for 24 hours in neurobasal medium. During the process, we further identified whether PI3K/AKT signaling pathway is involved through the adjunction of LY294002 (a specific phosphatidylinositide-3-kinase (PI3K) inhibitor). Two hours later, the expression of pAKT (phosphorylated AKT) and AKT were analyzed by Western blotting. The length of axons, the expression of GAP-43 and the survival of neurons were measured at 48 hours.

Results

Both BMSCs and CM from BMSCs inreased the axonal length and GAP-43 expression in OGD-injured cortical neurons. There was no difference between the effects of BMSCs of 5×105/ml and of 5×103/ml on axonal outgrowth. Expression of pAKT enhanced significantly at 2 hours and the neuron survival increased at 48 hours after the injured neurons cultured with the CM, respectively. These effects of CM were prevented by inhibitor LY294002.

Conclusions/Significance

BMSCs promote axonal outgrowth and the survival of neurons against the damage from OGD in vitro by the paracrine effects through PI3K/AKT signaling pathway.  相似文献   

19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号