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In order to provide a basic theory for the materials of repairing central nervous system injury, we have studied the growth and differentiation of neural stem cells (NSCs) on poly (L-lysine) modified silk fibroin film. First, we used poly (L-lysine) to modify silk fibroin film and confirmed by UV-vis and 1H NMR spectra. Then NSCs were isolated and seeded on the silk fibroin film (Silk group), poly (L-lysine) (PLL group) and poly (L-lysine) modified Silk fibroin film (Silk-PIL group). The proliferation of NSCs was evaluated by Cell Counting Kit-8 (CCK-8) assay on days 1, 3, 5 and 7 after seeding. Immunofluorescence was used to analyze the differentiation of NSCs at the 7th day. The levels of apoptosis were detected by Western blotting and TUNEL. The mRNA level of brain derived neurotrophic factor (BDNF) was identified by real-time PCR. UV-vis and 1H NMR spectra confirmed that poly (L-lysine) was successfully grafted onto the silk fibroin film. From the 3rd day after seeding to the 7th day, the CCK-8 test showed that proliferation rate of NSCs in the Silk-PIL was significantly higher than Silk group (P<0.05) but had no significant difference compared with PLL group (P>0.05). Immunofluorescence staining displayed that more NSCs in Silk-PIL group were differentiated into neuron compared with Silk group (P<0.05), however, there was no significant difference compared with PLL group (P>0.05). The number of NSCs differentiated into astrocytes was not significantly different between the three groups. Western blotting and TUNEL test presented that the degree of apoptosis of NSCs in the Silk-PIL group was significantly lower than Silk group (P<0.05). RT-PCR exhibited that mRNA level of brain derived neurotrophic factor (BDNF) of NSCs was higher in Silk-PIL group compared with Silk group (P<0.05) but had no significant difference compared with PLL group (P>0.05). Thus, poly (L-lysine) modified silk fibroin film could promote the proliferation of NSCs and reduce NSCs apoptosis. Furthermore, it also can enhance the differentiation of NSCs into neurons. It is expected to become a new type of tissue engineering scaffold carrying NSCs to repair central nervous system injury.
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AIM:To evaluate the influence of scutellarin on the expression of vascular endothelial growth factor ( VEGF) in high glucose-treated human retinal pigment epithelial cell line ARPE-19 and to observe the effects of scutellarin on the protein expression of VEGF, p-ERK and VEGFR2 in the retinas of type II diabetic rats.METHODS: Cultured ARPE-19 cells were divided into normal control group, scutellarin group, high glucose group and high glucose+scutellarin group.The protein levels of VEGF, p-ERK and VEGFR2 were measured by Western blot.The VEGF release in ARPE-19 cells was detected by ELISA.Normal rats were randomly divided into normal control group and scutellarin group.Diabetic rat model was established by feeding with high-fat diet and injecting with streptozocin, and randomly divided into diabetes group and diabetes treated with scutellarin group.After 16 weeks, the eyes were removed.The morphological changes of the retinas were observed under light microscope with HE staining, and histopathological score was recorded.The expres-sion of VEGF in the retinas was observed by the method of immunohistochemistry.RESULTS:Compared with normal con-trol group, the protein levels of VEGF, p-ERK and VEGFR2 in the ARPE-19 cells decreased in scutellarin group, but in-creased in high glucose group.The histopathological score of the retinas showed significant difference among diabetes group, diabetes treated with scutellarin group and normal control group, and no significant difference between normal con-trol group and scutellarin group was observed.The expression of VEGF increased in diabetic group and was significantly higher than that in scutellarin treatment group (P<0.05).CONCLUSION:Scutellarin inhibits the increased protein le-vels of VEGF, p-ERK and VEGFR2 in ARPE-19 cells, and decreases the expression of VEGF in the retinas of diabetic rats.The suppression of the diabetic retinopathy development by scutellarin may be partly involved in the ERK/MAPK pathway.
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AIM: To investigate the effect of cobalt chloride (CoCl2) on the apoptosis of neural stem cells (NSCs) and the expression of microRNA-26a (miR-26a) in vitro, and to explore the mechanisms of NSC apoptosis in-duced by CoCl 2 .METHODS:NSCs were exposed to CoCl 2 at different doses (200~600μmol/L) for 24 h.The cell via-bility and apoptosis were measured by CCK-8 assay and TUNEL method.The expression of miR-26a-3p, miR-26a-5p, GSK-3β, caspase-3, Bcl-2 and Bax was examined by real-time PCR.The protein levels of Bcl-2 and Bax were detected by Western blotting .RESULTS: The cell viability was inhibited and the apoptosis of NSCs was increased significantly by CoCl2 in a dose-dependent manner (P<0.05).CoCl2 at concentration of 400μmol/L for 24 h was used to induce apopto-sis and the expression of miR-26a was down-regulated compared with control (P<0.05).Exposure to CoCl2 at concentra-tion of 400μmol/L up-regulated the expression of GSK-3β, caspase-3 and Bax , down-regulated the expression of Bcl-2 and Bcl-2/Bax (P<0.05).CONCLUSION:CoCl2 at concentration of 400μmol/L induces the apoptosis of NSCs obviously . CoCl2 may induce the NSC apoptosis by mitochondrial apoptotic pathway .Declining miR-26a may be related to NSC apopto-sis.
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BACKGROUND:Hyperbranched cationic amylopectin is a kind of nonviral gene vectors with low toxicity and good transfection efficiency. However, searching for more efficient methods to delivery it into the body and making the genes expressed are being explored. OBJECTIVE:To study the expression of DMAPA-Amp wrapped green fluorescent protein (GFP) transferred by modified carotid injection into cerebral ischemic area. METHODS:Male Sprague-Dawley rats subjected to middle cerebral artery infarction were randomly divided into two groups after 24 hours:experimental group (injected with GFP entrapped DMAPA-Amp via the internal carotid artery) and control group (injected with GFP entrapped DMAPA-Amp via the tail vein). These rats were put to death and their brain tissue was removed after 7 days. The expression of GFP was detected by quantitative PCR and western blot assay, and immunofluorescence staining was performed to detect the expression of GFP located near cerebrovascular endothelial cel s by frozen section. RESULTS AND CONCLUSION:Compared with the control group, the expression of GFP was much higher in the experimental group detected by quantitative PCR and western blot (P< 0.05). Additional y, the expression of GFP located near cerebrovascular endothelial cel s by frozen section was also higher than that in the control group. Modified carotid injection could significantly promote the expression of hyperbranched cationic amylopectin derivates and GFP in the brain tissue of Sprague-Dawley rats undergoing middle cerebral artery infarction compared with tail vein injection, which indicates DMAPA-Amp and modified carotid injection may cast new lights on the therapy for angiogenesis of ischemic stroke.
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BACKGROUND:Previous studies have demonstrated that transplantation of control ed release glial cellline-derived neurotrophic factor and bone marrow mesenchymal stem cells-derived neuron-like cells can effectively promote the motor function and sensory function recovery of rhesus monkeys with spinal cord injury. OBJECTIVE:To validate whether co-transplantation of control ed release glial cellline-derived neurotrophic factor and bone marrow mesenchymal stem cells-derived neuron-like cells exhibits better protective effects on spinal cord glial scar of rhesus monkeys with spinal cord injury than celltransplantation alone. METHODS:Twelve rhesus monkeys were col ected to prepare animal models of acute severe spinal cord injury using modified Al en’s method, and then randomly divided into three groups:experimental group, co-transplantation of control ed release glial cellline-derived neurotrophic factor and bone marrow mesenchymal stem cells-derived neuron-like cells;control group, simple transplantation of bone marrow mesenchymal stem cells-derived neuron-like cells;blank control group, PBS. After 5 months, paraffin specimens of the spinal cord were made for detection of morphological and compositional characteristics of glial scar, regeneration of nerve fibers in the scar, glial scar area, and average absorbance of glial fibril ary acidic protein. RESULTS AND CONCLUSION:Glial scar in the injured spinal cord was composed of astrocytes and histocytes. Less spinal cord glial scar area and lower absorbance value could be observed in the experimental and control groups as compared with the blank control group (P<0.05). In addition, in the blank control group, neurofilament negative fibers could be observed in the glial scar, and astrocytes proliferated obviously. The experimental and control groups showed less fibers passed through the scar area. The glial scar area and average absorbance in the experimental group was lower than that in the control group (P<0.05). These findings suggest that compared with simple transplantation of bone marrow mesenchymal stem cells-derived neuron-like cells, co-transplantation of control ed release glial cellline-derived neurotrophic factor and bone marrow mesenchymal stem cells-derived neuron-like cells shows better protective effects spinal tissue structure after spinal cord injury, which may be one of mechanisms by which the number of glial scars is reduced to a greater extent.
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Gene therapy has been considered as a promising method for treatment of many diseases, such as acquired and genetic diseases. At present, there are two major vehicles for gene delivery including viral vectors and nonviral vectors. Viral vectors appear as high gene transfection efficiency, but some deficiencies such as inflammatory responses, recombination and mutagenesis have limited their use. On account of low pathogenicity, safety and cost-effectiveness, nonviral vectors have been attracted much attention. Cationic polymers are one of the nonviral vectors which have been widely studied. This review focuses on the structure of the cationic polymers and the interaction mechanism between the vector and DNA. We try to provide a framework for the future design and synthesis of nonviral vectors with high transfection efficiency and low toxicity for gene therapy.
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Cations , Chemistry , DNA , Genetics , Gene Transfer Techniques , Genetic Therapy , Methods , Genetic Vectors , Genetics , Polymers , ChemistryABSTRACT
The aim of this study is to investigate the growth and proliferation of bone marrow mesenchymal stem cells (BMSCs) three-dimensionally cultured in Pluronic F-127 gel, in order to explore the cellular compatibility of gel and to investigate the feasibility of BMSCs differentiating into adipocytes in gel. Rat BMSCs were isolated from adult bone marrow, and then cultured and amplified in vitro. The BMSCs derived from the 4th passage were seeded on the scaffolds and incubated in adipogenic stimuli culture to differentiate into adipocytes. BMSCs were dispersed into gel and cultured in vitro for two weeks then the status of adhesion, growth and proliferation of the cells were observed. The edipogenic differentiation of the BMSCs was assessed by cellular morphology and further confirmed by Oil Red O staining. BMSCs were able to attach, grow and proliferate well in Pluronic F-127 gel. The BMSCs differentiated into adipocytes in gel in the presence of adipogenic stimuli over a period of 2 weeks. After only 4 days of adipogenic induction, small lipid droplets were observed within BMSCs in gel wells treated with differentiation media. At the end of 14 days, in the presence of differentiation media in gel, the size of the lipid droplets increased to occupy most of the cytoplasm, consistent with differentiation of BMSCs into adipocytes. Lipid droplets in differentiating BMSCs were positively stained with Oil Red O in the presence of differentiation media in the Pluronic F-127 treatment. We demostrated BMSCs incubated in the 3D Pluronic F-127 gel scaffolds could be induced and differentiated into adipocytes. The system for inducing differentiation of BMSCs into adipocytes is promising to apply in the construction of tissue engineering adipose tissue and the repair of fat injury, and Pluronic F-127 gel may be a suitable scaffold for cellular therapy of BMSCs.
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Animals , Rats , Adipocytes , Cell Biology , Adipose Tissue , Cell Biology , Bone Marrow Cells , Cell Biology , Cell Differentiation , Cells, Cultured , Hydrogels , Chemistry , Mesenchymal Stem Cells , Cell Biology , Poloxamer , Chemistry , Rats, Sprague-Dawley , Tissue EngineeringABSTRACT
This study was aimed to develop non-toxic, high transfection efficiency polyethyleneimine(PEI) cationic nanoparticles. The exosyndrome of PEI cationic nanoparticles was measured by zeta sizer, ultraviolet and visible spectroscopy. The condensation ability and the resistance to DNaseI of pEGFP-N1/PEI and pEGFP-N1/PEI modified polyethylene glycol(PEG) were evaluated by agarose gel electrophoresis. The cell toxicity of polyethyleneimine cationic nanoparticles was measured by using MTT test. The orthogonal design was used to optimize the transfection efficiency with the N/P ratio, the grafting ratio and the gene dosage as the factors. The experimental results showed that pEGFP-N1/PEI nanoparticles have lower cell toxicity, better composite ability and better resistance to DNAseI. The highest transfection efficiency of PEI cationic nanoparticles was 91% by using the PEI nanoparticles with the N/P ratio 40:1 and gene dosages 6 microg/well. PEI cationic nanoparticle modified by PEG effectively transferred DNA to hepatoma carcinoma cells and it is a non-toxic, with high transfection efficiency, and a promising non-viral carrier for gene delivery. The transfection efficiency will be improved by optimizing the experiment condition.
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Humans , Carcinoma, Hepatocellular , Genetics , Pathology , Cell Line, Tumor , Gene Transfer Techniques , Liver Neoplasms , Genetics , Pathology , Nanoparticles , Chemistry , Polyethylene Glycols , Chemistry , Polyethyleneimine , Chemistry , Transfection , MethodsABSTRACT
Polyethylenimine (PEI) is a kind of nanometer nonviral vector frequently applied in gene transfection. It is simple and easy to prepare and to modify and relatively safe compared to viral vectors. In recent years, PEI has been utilized in many research areas for gene delivery to stem cells in vitro or targeted gene delivery to cells in the brain. This review reveals that the cytotoxicity and low transfection efficiency of PEI requires to be improved. However brain-targeted modification indicates the promising prospect of PEI for gene therapy in cerebrovascular diseases.
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Humans , Genetic Therapy , Genetic Vectors , Nanostructures , Chemistry , Polyethyleneimine , Chemistry , Stem Cell Transplantation , Methods , Transfection , MethodsABSTRACT
AIM: To explored the potential role of HIF-1α in reducing the neuronal apoptosis and promoting the neuronal proliferation after stroke in rats. METHODS: The bone marrow-derived mesenchymal stem cells (BMSCs) were lentivirally transduced to express the stable form of HIF-1α. Ischemic stroke was induced by permanent middle cerebral artery occlusion (MCAO) in Sprague-Dawley rats. Neurological function was evaluated by modified neurological severity score (mNSS). Cerebral infarct volume was measured by TTC staining. Immunohistochemistry and terminal deoxynucleotidyltransferase mediated dUTP nick end labeling (TUNEL) method were performed to detect neuronal proliferation and apoptosis. RESULTS: Significant improvement of neurological deficits was found in BMSCs-mHIF-1α rats as compared to the control animals at 14th d and 28th d after MCAO (P<0.05). Significant reduction of infarct volume was observed in rats in BMSCs-mHIF-1α group at 3rd day after MCAO (P<0.05). Histological evaluation showed that BMSCs-mHIF-1α treatment significantly promoted neuronal survival and proliferation in the ischemic boundary area. CONCLUSION: Constitutive expression of HIF-1α in BMSCs reduces the neuronal apoptosis and promotes the neuronal proliferation after stroke in rats.
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BACKGROUND:Basic fibroblast growth factor(bFGF)belongs to active peptide,which is an effective mitogenic factor.OBJECTIVE:To investigate the effect of bFGF on proliferation and differentiation of monkey bone marrow mesenchymal stem cells(BMMSCs)into neuronal precursor cells.METHODS:Monkey BMMSCs were in vitro cultured by density gradient centrifugation,and then divided into 4 groups after passaged,namely,control,bFGF with low,medium and high concentration groups.In the bFGF groups,0,3,6,10 μ/L bFGFwere applied.The proliferation of BMMSCs in each group were observed.The 5th BMMSCs were cultured with serum free L-DMEM culture medium containing 20 mg/L cryptotanshinone to differentiated into neuraMike cells.The expression of positive-nestin protein was detected by immunohistochemical method.RESULTS AND CONCLUSION:Compared with the control group,proliferation rate of BMMSCs in the bFGF groups were accelerated(P ＜ 0.05),which showed a positive correlation to the concentration of bFGF.The positive-nestin protein could be found in the low and medium concentration groups at 0.5 hours after induction,and reached a peak at 1.5 hours,which increased obviously in the low concentration group than that of the high concentration group(P ＜ 0.05).bFGF can promote BMMSCs proliferation in vitro,enhance inducing ratio of prophase neuron-like cells at lower concentration but inhibit differentiation at high level.
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Hypoxia-inducible factor-1 (HIF-1), as a nuclear transcription regulator of the hypoxic response, is up-regulated during hypoxia, and it regulates a series of downstream target gene expression, such as vascular endothelial growth factor, glucose transporter and erythropoietin through binding with hypoxia response element. It plays important roles in angiogenesis, anerobic metabolism, cell survival, proliferation, migration, and differentiation.This article reviews the structure, function and activity regulation of HIF-1 and its roles in acute ischemic brain injury.
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[Objective] To investigate the effects of preconditioning with low concentration of hydrogen peroxide (H2O2) on oxidative stress-induced BMSC apoptosis.[Methods] In vitro separation,purification,culture,and amplification of bone marrow mesenchymal stem cells were performed.BMSC were insulted with 0,50,100,200,300,400,500 μmol/L H2O2 and the effect of different consentration of H2O2 on BMSC was detected by Flow cytometry (FCM).And then cells were preconditioned with different consentraion of H2O2.(FCM) was used to determine the protective role of H2O2 preconditioning on BMSC apoptosis,BMSC chromatin distribution changes were observed by Hoechst33324;BMSC Caspase-3 and Bcl-2 gene changes were detected by RT-PCR.[Results] Analysis of BMSC apoptosis by flow cytometry showed that H2O2 induced BMSC apoptosis in a dose-dependent manner,and pretreatment of the cells with low concentration of H2O2 prevented subsequent stimulation with high H2O2.RT-PCR results showed that preconditioning with low concentration of H2O2 reduced the BMSC Caspase-3 gene expression but increased Bcl-2 gene expression.[Conclusion] Preconditioning with low concentration of H2O2 has an adaptive role in BMSC,and its mechanism may be related to inhibit abnormal gene expression of Caspase-3 and increase the gene expression of Bcl-2.
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Objective To determine the feasibility of magnetically labeling and tracking mesenchymal stem cells(MSCs)in vitro by using a gadolinium and fluorescent bi-functionally transfection agent of polyethylenimine.Methods A gadolinium bifunctional transfection reagent complex was obtained after the linear polyethylenimine derivative(JetPEI-FluoR)was incubated with Gd-DTPA.Mesenchymal stem cells isolated from the bone marrows of SD rats were cultured and expanded.The mesenchymal stem cells were incubated with the bi-functional labeling agents.After labeling,the MSCs were examined with fluoroscope and electron microscope and the biological characters were detected including trypan blue exclusion test,MTT,and apoptosis detection.On a 1.5 T MR system,the labeled MSCs were examined with spin echo T1 WI and T2 WI and T1 measurement with mixed sequence.After labeling,the cells were cultured and undergone routine passage.Prior MR examinations were repeated for each passage of labeled cells.All data was statistically prolessed with SPSS for Windows.Results Of 5×105 MSCs incubated with the bi-functional agents,4.25×105 MSCs were successfully labeled,the percentage of labeled MSCs was 85% fluoroscopically.The high density electron particles of gadolinium observed electron microscopically existed around cellular apparatuses,especially around Golgi apparatus.In trypan blue exclusion test,the exclusion rate of labeled MSCs with incubation duration of 3,6,12,24 h was(96.55±2.90)%,(94.17±2.56)%,(97.16±3.12)% and(94.23±2.67)%,respectively.The corresponding exclusion rate of unlabeled MSCs was(95.86±2.67)%,(92.04±2.21)%,(93.38±3.64)%and(92.12±2.53)%,respectively.There was no statistical difference of trypan blue exclusion rate between labeled cells and control unlabeled cells within 24 hours of incubation(F=4.523,P＞0.05).In the proliferation test,the optical absorption value of labeled MSC with 2.5,5.0,10.0,20.0,30.0 and 40.0 μl bi-functional labeling agent was(0.1884±0.0151),(0.1878±0.0190),(0.1741±0.0160),(0.1135±0.0215),(0.1079±0.0145)and(0.0811±0.0079),respectively.The corresponding optical absorption value of unlabeled MSCs was(0.1940±0.0116).The optical absorption value of labeled cells was not affected in case of less than 30.0 μl of Gd-DTPA(q'=0.2225-0.9458,P＞0.05).The apoptosis index for labeled cells and unlabeled cells were 5.08% and 3.86%,respectively.On T1 WI,the signal intensity and T1 relaxation time of unlabeled cells and labeled cells were 240.3±24.7 and(2457±56)ms,336.2±20.7 and(1102±64)ms,respectively,and there were significant statistical difference(t=12.656,17.889,P＜0.01).The minimal amount of cells which was detectable for T1 WI was 5×103.After routine passage,the gadolinium in the cells gradually decreased and could be tracked by MRI until the fifth passage.Conclusions The gadolinium and fluorescent bi-functionally labeling rat bone marrow mesenchymal stem cell by using the transfection agent of polyethylenimine is feasible,efficient and safe.The labeled cells could be tracked in vitro on MR imaging.
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<p><b>OBJECTIVE</b>To investigate the effect of shenqi fuzheng injection (SFI) in inducing differentiation of human mesenchymal stem cells (hMSCs) in brain stem and its effect on nervous function in model rats of cerebral infarction.</p><p><b>METHODS</b>Middle cerebral artery occlusion model rats were made, and hMSCs was injected into their brain after being amplified in vitro and incubated with SFI for 0.5 h, then the survival, migration and differentiation of hMSCs in brain stem as well as the change of nervous function in model rats were observed.</p><p><b>RESULTS</b>The post-transplantation reject reaction to hMSCs was low, it could survive as long as 6 weeks or more. No difference in area of infarction was shown before and after transplantation. Immunohistochemical staining showed that hMSCs expressed human neuron specific enolase (NSE), neurofilament (NF) and glial fibrillary acid protein (GFAP). The limb-kinetic function and tactile perception were improved in the model rats.</p><p><b>CONCLUSION</b>SFI can induce hMSCs differentiate into neurons in vivo, and hMSCs may be the ideal germinal cells for treating cerebral infarction.</p>
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Animals , Humans , Male , Rats , Brain , Metabolism , Cell Differentiation , Cell Division , Cells, Cultured , Cerebral Infarction , General Surgery , Culture Media , Drugs, Chinese Herbal , Pharmacology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Cell Biology , Neurofilament Proteins , Neurons , Cell Biology , Phosphopyruvate Hydratase , Rats, Sprague-Dawley , Transplantation, HeterologousABSTRACT
<p><b>OBJECTIVE</b>To prevent Graft-versus-host disease (GVHD) in rat model, we evaluated the feasibility of mesenchymal stem cells (MSCs) as a gene transfer target and studied the efficiency of recombinant adenovirus mediated gene therapy.</p><p><b>METHODS</b>We constructed the recombinant adenovirus containing CTLA4Ig gene. Rat MSCs of passages 3-5 were infected by the adenovirus, and the transfection efficiency was monitored by GFP markers. We performed flow cytometric analysis, immunohistochemical and Western blotting analysis to identify the CTLA4Ig expression. The gene transferred MSCs were tested for their ability to inhibit the allogeneic lymphocyte response in vitro and to prevent GVHD in a rat model.</p><p><b>RESULTS</b>Recombinant adenovirus pAd-CTLA4Ig was correctly constructed and confirmed. After MSCs were infected by the adenovirus, the CTLA4Ig protein was detected not only in transgenic MSCs, but also in the culture medium. In a mixed lymphocytes response (MLR) test, the transgenic MSCs could significantly inhibit the allogeneic lymphocyte response compared with the control groups (P < 0.05). A model of GVHD was developed by transplanting bone marrow cells and spleen lymphocytes of F344 rats to lethally irradiated SD rats. The onset of GVHD could be ameliorated or prevented by co-administration of transgenic MSCs. All the rats in the control groups suffered severe acute GVHD. CTLA4Ig expression was observed in the liver, intestine, kidney and spleen 30 days post-transplantation.</p><p><b>CONCLUSIONS</b>Our results indicate that adenoviral vectors could efficiently transfer CTLA4Ig gene into MSCs and sustain long-term stable expression in vitro and in vivo.</p>
Subject(s)
Animals , Rats , Abatacept , Adenoviridae , Feasibility Studies , Gene Transfer Techniques , Genetic Vectors , Graft vs Host Disease , Immunoconjugates , Genetics , Mesenchymal Stem Cells , Rats, Inbred F344 , Rats, Sprague-Dawley , Recombination, GeneticABSTRACT
Objective To search for a more efficient method to induce bone marrow stromal cells (BMSCs) into Schwann-liked cells (SLCs) in vitro. Methods On the base of the method which was used by Dezawa (it was looked as the traditional inducing method),some steps were modified,namely,to use all the reagents in half dose in the same time and two times intervally,this method was looked as the modified inducing method.After induced by the two methods,the cells morphologic characteristic,the positive ratio of immunocytochemical dye with anti-S-100 and anti-GFAP,the cells activity measured by MTT method and the DNA percentage in S period measured by flow cytometry were compared with each other respectively to evaluate the methods'effects. Results Compared with the traditional method,the cells induced by the modified method were more similar to the primary Schwann cells in morphology,more positive proportion in immunocytochemic dye with anti-S-100 and anti-GFAP,less damage in the activity and more percentage in S period. Conclusion The modified method had more advantages such as less damage on cells and more efficiency in inducing BMSCs into SLCs.
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Mesenchymal stem cells (MSCs) are a population of multipotent cells that can proliferate and differentiate into marrow and non-marrow cell types, such as adipocytes, chondrocytes, myocytes, and so on. In recent years, many researchers have studied whether MSCs are capable of differentiation into neurons in vivo and ex vivo. The result that MSCs-derived neurons express NSE and NF, but don't express GFAP suggests MSCs can differentiate into neurons, some researchers have achieved success in promoting functional recovery in Pakinsons and transactional spinal cord injury rat models by use of MSCs-derived neurons. Therefore, MSCs-derived neurons will play an important role in the therapy for a variety of diseases of the nervous system. [
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AIM:To explore the survivorship and the mechanism of the intravenous administration of bone marrow stromal stem cells(BMSCs) for treating permanent focal cerebral ischemia in rats.METHODS:After purified,proliferated,and marked with BrdU,the BMSCs were injected intravenously into rats 1 d after focal cerebral ischemia.Modified neurological severity score(mNSS) was evaluated before and following 1,7,14 and 28 d after middle cerebral artery occlusion(MCAO).Rats were executed at 1,7,14 and 28 d after MCAO.Brain sections were stained with hematoxylin and eosin(HE) for determining the infarct volume.Slides were stained by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling(TUNEL) and immunostaining for cleaved caspase-3 method for apoptosis detection and mechanism exploration in situ.RESULTS:mNSS in BMSCs-transplanted group at 14th day and 28th day of MCAO was significantly lower than that in control group(P
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AIM: To investigate the survival, migration and differentiation of human bone marrow mesenchymal stem cells (hMSC) in the middle cerebral artery occlusion (MACO) model and to observe the influence on motor function in the animal model. METHODS: hMSC with Hoeschst 33342 were injected into the animal model of MACO after Shenqiye induced for half an hour and their survival, migration, differentiation and the behavior changes in MACO rats were examined. RESULTS: hMSC had good homogeneousness and immunological reaction after implantation. The results showed that hMSC survived in rat brain for a long time over six weeks. As time going, hMSC were found in much more areas in the rat brain. Immunofluorescence staining suggested that implanted hMSC expressed human neuron specific enolase, neurofilament, and glial fibrillary acid protein. At the same time, improvements in abnormal behavior of MACO rats were observed. CONCLUSION: hMSC differentiate into neurons in the brain of rats, which means that hMSC is an ideal seed cells for the therapy of cerebral infarction.