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Objective:To investigate the genetic safety of allogeneic bone marrow mesenchymal stem cells (BMSCs) transplantation in traumatic brain injury (TBI).Methods:(1) In vivo experiment: BMSCs from male SD rats were isolated and cultured. Moderate TBI models were prepared by implanting and fixing micro-drug injection cannula into the left ventricle of 12 female SD rats, and 3 d after that, striking the right cerebral cortex of the rats with pneumatic precision percussion device was performed. Four h, and 3, 6, 9, and 12 d after modeling, TBI rats were given a single/multiple BMSCs infusion (2.5×10 5/time, total volume 10 μL) by cannula; 48 and 72 h, and 10 and 14 d after modeling, brain tissues of TBI rats (3 at each time point) were prepared into paraffin specimens. Immunofluorescent staining was used to detect the microglia activation, and RNAscope ? technology was used to detect the co-localization of astrocytes, neurons, microglia and transplanted BMSCs to observe whether the allogeneic BMSCs were integrated with the host brain cells after transplantation into TBI host. (2) In vitro experiment: the frozen and revived microglial cell line BV2 was transfected with green fluorescent protein (GFP)-positive lentiviral particles, and then, BMSCs prelabeled with pHrodo RED probe and BV2 cells pretreated with lipopolysaccharide were co-cultured in a certain ratio (BV2:BMSCs=1:1, 1:2, 2:1); after 36 and 72 h of co-culture, the phagocytosis between the 2 kinds of cells was observed under confocal fluorescence inverted microscope to observe the specific action forms of microglia on BMSCs. Results:(1) In vivo experiment: 48 and 72 h, and 10 and 14 d after modeling, no colocalization of transplanted BMSCs with astrocytes or neurons was found in paraffin sections of brain tissue in TBI rats; however, 10 and 14 d after modeling, microglia in TBI rats were obviously activated and migrated to the left lateral ventricle and choroid plexus, and co-localization of microglia with transplanted BMSCs was observed. (2) In vitro experiment: phagocytosis occurred after co-culture of BV2 cells at different proportions with BMSCs for 36 and 72 h. Conclusion:After transplantation, allogeneic BMSCs do not integrate with astrocytes or neurons of the TBI host, but they could be phagocytosed by microglia, indicating that allogeneic BMSCs transplantation for TBI is genetically safe.
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Objective @#To investigate the effects of Lin28 overexpression on the proliferation and osteogenic differentiation of human dental pulp stem cells (hDPSCs) through mTOR signaling pathway.@*Methods @#After transfecting lentiviral vectors of Lin28 gene in hDPSCs , the relative expression of Lin28 was detected by Real⁃time PCR. CCK⁃8 assay was applied to detect the effect on cell proliferation. qRT⁃PCR was used to research the expression levels of alkaline phosphatase (ALP) , osteopontin (OPN) and osteocalcin (OCN) . Western blot assay was processed to investigate the effects on the relative expression levels of ALP and OPN proteins. Alizarin red staining was utilized to detect the mineralized nodules. @*Results @#Compared with the control group , the cell proliferation of transfection group was promoted (P < 0. 05) ; The mRNA and protein expression levels of ALP , OPN and OCN in transfection group were significantly lower than those in control group (P < 0. 05) , the expression level of ALP apparently decreased after the addition of mTOR inhibitor rapamycin (P < 0. 05) ; Alizarin red staining showed that the size and number of mineralized nodules formed in transfection group were markedly declined compared with empty carrier group (P < 0. 05) .@*Conclusion @#Overexpression of Lin28 can inhibit the osteogenic differentiation of hDP⁃ SCs through suppress mTOR signaling pathway.
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Objective To investigate the expression profile of cancer-related genes in human bone marrow-derived neural stem cells (Md-NSCs) to determine whether there are any characteristics that could help the evaluation of their tumorigenic potentials.Methods Md-NSCs were cultured in vitro and identified (experimental group);fresh human adult bone marrow cells were used as control group (sifting erythrocytes).The expression profiles of 440 cancer-related genes in cells from the two groups were analyzed by Oligo GEArray Human Cancer Microarray OHS-802;real-time quantitative PCR was performed to detect the expressions of oncogene MYC,matrix metalloproteinase 2 (MMP2),Notch congener 2 (Notch2),stanniocalcin 1 (STC1),integrin α3 (ITGA 3),signal transduction and transcriptional activation factor 5b (STA T5b),Ras congene gene family C (RhoC),and wingless-type MMTV integration site family member 1 (Wnt1).Results As compared with those in the control group,the Md-NSCs from experimental group had 66 tumor-related genes with high expressions (＞3 folds).MYC,MMP2,Notch2,STCI,ITGA3,STA T5b,RhoC and Wnt1 expressions in the Md-NSCs from experimental group were significantly higher than those in the control group (P＜0.05),whose results were accorded with genechip detection results,enjoying the folds of 4.35×100,2.84×100,2.87×100,3.41 ×102,2.22×102,6.99× 100,4.92 × 100 and 3.64 ×100,respectively.Conclusion A number of cancer-related genes are over-expressed in Md-NSCs,and the activations of some of these important oncogenes have been proved to promote human tumorigenesis.
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BACKGROUND: Studies regarding Feridex in vitro cell labeling are mainly in rodents, while little information is known on primate crab-eating macaque.OBJECTIVE: To explore the feasibility of protocols using Feridex and transfection agents for in vitro magnetic labeling of bone marrow stromal cells (BMSCs) in crab-eating macaque.METHODS: Under the sterile condition, the crab-eating macaque BMSCs were obtained by means of density gradient centrifugation following a bone puncture. Feridex-poly-l-lysine complexes were used to magnetically label BMSCs. The efficiency and cellular viability of Feridex-poly-l-lysine labeled BMSCs were evaluated by Prussian blue staining, electron microscopy, and trypan blue dye exclusion test. The proliferation and differentiation ability of Feridex-poly-l-lysine labeling BMSCs were also investigated by inverted phase contrast microscope and immunocytochemistry. RESULTS AND CONCLUSION: BMSCs could be effectively labeled by Feridex and labeling efficiency was around 99%. Tiny blue stained fine particles and numerous vesicles coated with the electron-dense magnetic iron particles could be found in the cytoplasm of Feridex-poly-l-lysine labeled BMSCs under optical microscopy and transmission electron microscopy respectively. Cell viability, proliferation and differentiation ability of labeled BMSCs were not affected by Feridex-poly-l-lysine labeling. Results indicated that Feridex might be used to label BMSCs of crab-eating macaque.
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Objective To analyze the gene expression profiles in relation to the migration ability of adult human bone marrow-derived neural stem cells (Md-NSCs), and identify the genetic basis of the high migration potential of Md-NSCs in the central nervous system (CNS). Methods Adult human bone marrow stromal celIs(BMSCs) obtained from adult healthy volunteers were induced to differentiate into Md-NSCs in vitro, and the expressions of the genes related to cell invasiveness and metastasis were investigated by microarray analysis. Quantitative real-time PCR (RT-PCR) was used to verify the microarray results. Results The results of microarray analysis revealed significant overexpressions of the genes MMP1, MMP2, MMP17, ITGA3, RhoB, RhoC and RhoD in the Md-NSCs as compared with the expressions in fresh normal human adult bone marrow cells depleted of red blood cells. Quantitative RT-PCR verified the overexpression ofMMP2 gene by 2.84×100 folds, ITGA3 gene by 2.22×102folds, and RhoC gene by 4.92×100 folds. Conclusion The high migration potential of the Md-NSCs in the CNS is probably associated with the overexpression of the genes that promote cell invasiveness and metastasis. These overexpressed genes are also important oncogenes, and therefore the tumorigenicity of the Md-NSCs warrants further investigation.