Exploring the Mechanism of CircRNA-vgll3 in Osteogenically Differentiated Human Bone Marrow Mesenchymal Stem Cells

Objective:To explore the mechanism of circRNA-vgll3 in osteogenic differentiation of human bone marrow mesenchymal stem cells.Methods:BMSCs cells were transfected with circRNA-vgll3,and divided into circRNA-vgll3 high-level group,circRNA-vgll3 low-level group,and negative control group(circRNA-vgll3 not transfected)according to the amount of transfection.The proliferation and apoptosis of BMSCs osteoblasts in each group were analyzed,and the alkaline phosphatase(ALP)activity,type I collagen gray value,bone morphogenetic protein 2(BMP-2),Runx2 protein,and mRNA expression levels were detected.Results:The circRNA-vgll3 low-level group had a significant inhibitory effect on the proliferation of BMSCs osteoblasts,and the apoptosis rate of the circRNA-vgll3 low-level group was significantly higher than that of the circRNA-vgll3 high-level group(P<0.05);ALP activity,type I collagen gray value,BMP-2,Runx2 protein,and mRNA expression levels in the high-level circRNA-vgll3 group were significantly higher than those in the low-level circRNA-vgll3 group,and the difference was statistically significant(P<0.05).Conclusion:Overexpression of circRNA-vgll3 can promote the osteogenic differentiation ability of BMSCs,while low expression of circRNA-vgll3 can inhibit the osteogenic differentiation ability of BMSCs.The main mechanism of action is that circRNA-vgll3 can affect osteogenic differentiation by regulating the Runx2 protein.

Mesenchymal Stromal Cells Derived from Human Embryonic Stem Cells, Fetal Limb and Bone Marrow Share a Common Phenotype but Are Transcriptionally and Biologically Different

Mesenchymal stromal cells (MSCs) can be obtained from several sources and the significant differences in their properties make it crucial to investigate the differentiation potential of MSCs from different sources to determine the optimal source of MSCs. We investigated if this biological heterogeneity in MSCs from different sources results in different mechanisms for their differentiation. In this study, we compared the gene expression patterns of phenotypically defined MSCs derived from three ontogenically different sources: Embryonic stem cells (hES-MSCs), Fetal limb (Flb-MSCs) and Bone Marrow (BM-MSCs). Differentially expressed genes between differentiated cells and undifferentiated controls were compared across the three MSC sources. We found minimal overlap (5% - 16%) in differentially expressed gene sets among the three sources. Flb-MSCs were similar to BM-MSCs based on differential gene expression patterns. Pathway analysis of the differentially expressed genes using Ingenuity Pathway Analysis (IPA) revealed a large variation in the canonical pathways leading to MSC differentiation. The similar canonical pathways among the three sources were lineage specific. The Flb-MSCs showed maximum overlap of canonical pathways with the BM-MSCs, indicating that the Flb-MSCs are an intermediate source between the less specialised hES-MSC source and the more specialised BM-MSC source. The source specific pathways prove that MSCs from the three ontogenically different sources use different biological pathways to obtain similar differentiation outcomes. Thus our study advocates the understanding of biological pathways to obtain optimal sources of MSCs for various clinical applications.

HNF-4α determines hepatic differentiation of human mesenchymal stem cells from bone marrow

AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induced into hepatocyte-like cells following a previously published protocol. The differentiation status of the hepatocyte-like cells was compared with various human hepatoma cell lines. Overexpression of hepatocyte nuclear factor (HNF)-4α was mediated by adenovirus infection of these hepatocyte-like cells. The expression of interesting genes was then examined by either re-verse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that the differentiation status of hepatocyte-like cells induced from human MSCs was relatively similar to poorly differentiated human hepatoma cell lines. Interestingly, the HNF-4 isoform in induced MSCs and poorly differentiated human hepatoma cell lines was identified as HNF4γ instead of HNF-4α. Overexpression of HNF-4α in induced MSCs significantly enhanced the expression level of hepatic-specific genes, liver-enriched transcription factors, and cytochrome P450 (P450) genes. CONCLUSION: Overexpression of HNF-4α improves the hepatic differentiation of human MSCs from bone marrow and is a simple way of providing better cell sources for clinical applications.

Cardiomyocyte-like differentiation of human bone marrow mesenchymal stem cells after exposure to 5-azacytidine in vitro

Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073g/mL Percoll and propagated in the right cell culturing medium as previously described. The phenotypes of hMSCs were characterized with the use of flow cytometry. The hMSCs were cultured in cell culture medium (as control) and medium mixed with 5-aza for cellular differentiation. We examined by immunohistochemistry at 21 days the inducement of desmin, cardiac-specific cardiac troponin I (cTnI), GATA 4 and connexin-43 respectively. Results The hMSCs are fibroblast-like morphology and express CD44+ CD29+ CD90+ / CD34- CD45- CD31- CD11a. After 5-aza treatment, 20-30% hMSCs connected with adjoining cells and coalesced into myotube structures after 14days. Twenty-one days after 5-aza treatment, immunofluorescence showed that some cells expressed desmin,GATA4, cTnI and connexin-43 in 5,10 μmol/L 5-aza groups, but no cardiac specific protein was found in neither 3μmol/L 5-aza group nor in the control group. The ratio of cTnI positively stained cells in 10 μmol/L group was higher than that in 5 μmol/L group (65.3 ± 4.7% vs 48.2 ± 5.4%, P ＜ 0.05). Electron microscopy revealed that myofilaments were formed. The induced cells expressed cardiac-myosin heavy chain (MyHC) gene by reverse transcription-polymerase chain reaction (RT-PCR). Conclusions Theses findings suggest that hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration. (J Geriatr Cardiol 2004;1(2) :101-107. )

The genomic landscapes of histone H3-Lys9 modifications of gene promoter regions and expression profiles in human bone marrow mesenchymal stem cells

Mesenchymal stem cells （MSCs） of nonembryonic origins possess the proliferation and multi-lineage differentiation potentials. It has been established that epigenetic mechanisms could be critical for determining the fate of stem cells, and MSCs derived from different origins exhibited different expression profiles individually to a certain extent. In this study, ChiP-on-chip was used to generate genome-wide histone H3-Lys9 acetylation and dimethylation profiles at gene promoters in human bone marrow MSCs. We showed that modifications of histone H3-Lys9 at gene promoters correlated well with mRNA expression in human bone marrow MSCs. Functional analysis revealed that many key cellular pathways in human bone marrow MSC self-renewal, such as the canonical signaling pathways, cell cycle pathways and cytokine related pathways may be regulated by H3-Lys9 modifications. These data suggest that gene activation and silencing affected by H3-Lys9 acetylation and dimethylation, respectively, may be essential to the maintenance of human bone marrow MSC self-renewal and multi-potency.

Comparative characterization of human fetal neural stem cells and induced neural stem cells from peripheral blood mononuclear cells

Human-induced neural stem cells(iNSCs)transplantation is a potential treatment of neurodegeneration diseases.However,whether the reprogrammed cells have the same characterizations as human fetal neural stem cells needs further exploration.Here we isolated human fetal neural stem cells from aborted 12-week fetal brains and compared with iNSCs reprogrammed from human peripheral blood mononuclear cells in gene expression,proliferation ability,differentiation capacity,and the responses to tumor necrosis factor-α.We found that iNSCs and NSCs both expressed neural stem cell markers Nestin,SOX1,and SOX2.However,only iNSCs can be patterned into dopaminergic neurons and motor neurons.Furthermore,both iNSCs and NSCs can differentiate into oligodendrocyte progenitor cells.In addition,a low dose of tumor necrosis factor-αdid not inhibit the proliferation and differentiation of iNSCs and NSCs.In conclusion,iNSCs have properties similar to,and even better than,fetal neural stem cells and may be suitable for disease modeling and transplantation.

The related effects of astragalus polysaccharides on the improvement of bone marrow suppression and hematopoietic stem cells during chemotherapy in elderly patients with lung cancer

Objective:To investigate the effects of astragalus polysaccharides(APS)on bone marrow suppression and hematopoietic stem cells during chemotherapy in elderly patients with lung cancer.Methods:120 elderly patients with lung cancer treated in the first hospital of Xingtai city from January 2019 to early December 2019 were divided into the treatment group and the control group by the random number table method,all of whom received pemetrexed+carboplatin chemotherapy,and the treatment group was treated with APS at the same time.The efficacy was evaluated after 2 cycles of chemotherapy,bone marrow suppression was observed,and levels of TCM symptoms score,peripheral blood T lymphocyte subgroup index,L-selectin(CD62L)and macrophage differentiation antigen-1(Mac-1)were measured before and after 2 cycles of chemotherapy.Results:The response rate(RR)was 56.67%in the treatment group and 45.00%in the control group,with no statistically significant difference(P>0.05);The disease control rate(DCR)in the treatment group was 81.67%,which was significantly higher than 65.00%in the control group(P<0.05);The reduction degree of leukopenia in the treatment group was significantly lower than that in the control group(P<0.05);The treatment group had a platelet reduction of grade 1+2 at a rate of 40.00%,and hemoglobin reduction of grade 1+2 at a rate of 28.33%,which were significantly lower than the control group at 65.00%and 58.33%(P<0.05);Compared with those before chemotherapy,the total score of TCM symptoms,serum CD62L and Mac-1 levels in the two groups all decreased significantly after chemotherapy,and they were significantly lower in the treatment group than in the control group(P<0.05);After chemotherapy,CD3+,CD4+and CD4+/CD8+in the treatment group increased significantly and they were all higher in the treatment group than in the control group,while CD8+decreased significantly and was lower in the treatment group than in the control group(P<0.05).There was no statistically significant difference in T lymphocyte subsets before and after chemotherapy in the control group(P>0.05).Conclusion:Astragalus polysaccharide can improve the chemotherapy effect and improve the bone marrow suppression in elderly patients with lung cancer,which may be related to its obvious enhancement of immune function and decrease of CD62L and Mac-1 levels.

Effects of transplantation of human bone marrow mesenchymal stem cells in rats with liver failure

Objective: To investigate the effect of hepatic differentiation of human bone marrow mesenchymal stem cells (HBMSCs) induced in vitro and transplanted into rats with liver failure via portal vein, and observe the changes of liver function and pathological tissue. Method:After passage to the 6th generation in vitro, the hepatic differentiation was induced by HGFand EGF inducible factors. CCL4 acute liver failure model in rats were established, and randomly divided into 5 groups transplanted with differentiated stem cells via portal vein. These five groups included HGF-differentiated HBMSCs transplantation, EGF-differentiated HBMSCs transplantation, EGF+HGF-differentiated HBMSCs transplantation, non-differentiated HBMSCs transplantation, and non-HBMSCs transplantation. Liver function and pathological changes were detected. Results: Rats models survival, serum albumin, aminotransferase and coagulation indexes were observed at 12 h, 72 h, 7 d, 1 month and 2 months after treatment. The results showed that the survival and albumin, aminotransferase and coagulation function of rats were improved significantly after treatment in HGF-differentiated, EGF-differentiated, EGF+HGF-differentiated and non-differentiated transplantation groups, compared tothe non-HBMSCstransplantation group(P<0.05), while no significance was observed in above four groups(P>0.05).Pathological changes was ameliorated in the liver of rat models in HGF-, EGF-, EGF+HGF- and non-differentiated transplantation groups, compared to the non-HBMSCs transplantation group. Conclusion: Liver-differentiated BMSCs transplanted into rats with liver failure could effectively improve liver function and survival rate.

Human embryonic stem cell-derived mesenchymal stem cells improved premature ovarian failure

BACKGROUND Premature ovarian failure(POF)affects many adult women less than 40 years of age and leads to infertility.According to previous reports,various tissue-specific stem cells can restore ovarian function and folliculogenesis in mice with chemotherapy-induced POF.Human embryonic stem cells(ES)provide an alternative source for mesenchymal stem cells(MSCs)because of their similarities in phenotype and immunomodulatory and anti-inflammatory characteristics.Embryonic stem cell-derived mesenchymal stem cells(ES-MSCs)are attractive candidates for regenerative medicine because of their high proliferation and lack of barriers for harvesting tissue-specific MSCs.However,possible therapeutic effects and underlying mechanisms of transplanted ES-MSCs on cyclophosphamide and busulfan-induced mouse ovarian damage have not been evaluated.AIM To evaluate ES-MSCs vs bone marrow-derived mesenchymal stem cells(BMMSCs)in restoring ovarian function in a mouse model of chemotherapy-induced premature ovarian failure.METHODS Female mice received intraperitoneal injections of different doses of cyclophosphamide and busulfan to induce POF.Either human ES-MSCs or BMMSCs were transplanted into these mice.Ten days after the mice were injected with cyclophosphamide and busulfan and 4 wk after transplantation of the ESMSCs and/or BM-MSCs,we evaluated body weight,estrous cyclicity,folliclestimulating hormone and estradiol hormone concentrations and follicle count were used to evaluate the POF model and cell transplantation.Moreover,terminal deoxynucleotidyl transferase mediated 2-deoxyuridine 5-triphosphate nick end labeling,real-time PCR,Western blot analysis and immunohistochemistry and mating was used to evaluate cell transplantation.Enzyme-linked immunosorbent assay was used to analyze vascular endothelial growth factor,insulin-like growth factor 2 and hepatocyte growth factor levels in ES-MSC condition medium in order to investigate the mechanisms that underlie their function.RESULTS The human ES-MSCs significantly restored hormone secretion,survival rate and reproductive function in POF mice,which was similar to the results obtained with BM-MSCs.Gene expression analysis and the terminal deoxynucleotidyl transferase mediated 2-deoxyuridine 5-triphosphate nick end labeling assay results indicated that the ES-MSCs and/or BM-MSCs reduced apoptosis in the follicles.Notably,the transplanted mice generated new offspring.The results of different analyses showed increases in antiapoptotic and trophic proteins and genes.CONCLUSION These results suggested that transplantation of human ES-MSCs were similar to BM-MSCs in that they could restore the structure of the injured ovarian tissue and its function in chemotherapy-induced damaged POF mice and rescue fertility.The possible mechanisms of human ES-MSC were related to promotion of follicular development,ovarian secretion,fertility via a paracrine effect and ovarian cell survival.

Conditions to improve expansion of human mesenchymal stem cells based on rat samples

AIM: To improve the isolation and expansion of human marrow-derived mesenchymal stem cells (MSCs) based on rat samples. METHODS: Based on the fact that rat MSCs are relatively easy to obtain from a small aspirate, bone marrow-derived MSCs from rat were cultured and characterized to set up the different protocols used in this study. Then, accordingly, almost the same protocols were performed on human healthy bone marrow samples, after obtaining approval of the ethics committee and gaining informed consent. We used different protocols and culture conditions, including the type of basal media and the culture composition. The MSCs were characterized by immunophenotyping and differentiation. RESULTS: There was no difference in morphology and proliferation capacity between different culture media at the first passage. During the 5-7th passages, the cells gradually lost their morphology and proliferation potential on Dulbecco’s modified Eagle’s medium (DMEM) high glucose and α modified Eagle’s medium. Although the cells expanded rapidly for up to 10 passages on DMEM low glucose containing 10% to 15% fetal calf serum (FCS), their proliferation was arrested without change in morphology and differentiation capacity at the third passage on 5% FCS. Flow cytometric analysis and functional tests confirmed that more than 90% of marrow cells which were isolated and expanded by our selective protocols were MSCs. CONCLUSION: We improved the isolation and expansion of human bone marrow derived MSCs, based on rat sample experiments, for further experimental and clinical use.

Differentiation of mesenchymal stem cells into neuronal cells on fetal bovine acellular dermal matrix as a tissue engineered nerve scaffold

The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.

Human bone marrow mesenchymal stem cell transplantation attenuates axonal injury in stroke rats

Previous studies have shown that transplantation of human bone marrow mesenchymal stem cells promotes neural functional recovery after stroke, but the neurorestorative mechanisms remain largely unknown. We hypothesized that functional recovery of myelinated axons may be one of underlying mechanisms. In this study, an ischemia/reperfusion rat model was established using the middle cerebral artery occlusion method. Rats were used to test the hypothesis that intravenous transplantation of human bone marrow mesenchyrnal stem cells through the femoral vein could exert neuroprotective effects against cerebral ischemia via a mechanism associated with the ability to attenuate axonal injury. The results of behavioral tests, infarction volume analysis and immunohistochemistry showed that cerebral ischemia caused severe damage to the myelin sheath and axons. After rats were intravenously transplanted with human bone marrow mesenchymal stem cells, the levels of axon and myelin sheath-related proteins, including microtubule-associated protein 2, myelin basic protein, and growth-associated protein 43, were elevated, infarct volume was decreased and neural function was improved in cerebral ischemic rats. These findings suggest that intravenously transplanted human bone marrow mesenchymal stem cells promote neural function. Possible mechanisms underlying these beneficial effects include resistance to demyelination after cerebral ischemia, prevention of axonal degeneration, and promotion of axonal regeneration.

Bioactive materials from berberine-treated human bone marrow mesenchymal stem cells promote alveolar bone regeneration by regulating macrophage polarization

Alveolar bone regeneration has been strongly linked to macrophage polarization.M1 macrophages aggravate alveolar bone loss,whereas M2 macrophages reverse this process.Berberine(BBR),a natural alkaloid isolated and refined from Chinese medicinal plants,has shown therapeutic effects in treating metabolic disorders.In this study,we first discovered that culture supernatant(CS)collected from BBR-treated human bone marrow mesenchymal stem cells(HBMSCs)ameliorated periodontal alveolar bone loss.CS from the BBR-treated HBMSCs contained bioactive materials that suppressed the M1 polarization and induced the M2 polarization of macrophages in vivo and in vitro.To clarify the underlying mechanism,the bioactive materials were applied to different animal models.We discovered macrophage colony-stimulating factor(M-CSF),which regulates macrophage polarization and promotes bone formation,a key macromolecule in the CS.Injection of pure M-CSF attenuated experimental periodontal alveolar bone loss in rats.Colony-stimulating factor 1 receptor(CSF1R)inhibitor or anti-human M-CSF(M-CSF neutralizing antibody,Nab)abolished the therapeutic effects of the CS of BBR-treated HBMSCs.Moreover,AKT phosphorylation in macrophages was activated by the CS,and the AKT activator reversed the negative effect of the CSF1R inhibitor or Nab.These results suggest that the CS of BBR-treated HBMSCs modulates macrophage polarization via the M-CSF/AKT axis.Further studies also showed that CS of BBR-treated HBMSCs accelerated bone formation and M2 polarization in rat teeth extraction sockets.Overall,our findings established an essential role of BBR-treated HBMSCs CS and this might be the first report to show that the products of BBR-treated HBMSCs have active effects on alveolar bone regeneration.

Comparison of phenotypic markers and neural differentiation potential of multipotent adult progenitor cells and mesenchymal stem cells

AIM: To compare the phenotypic and neural differentiation potential of human bone marrow derived multipotent adult progenitor cells (MAPC) and mesenchymal stem cells (MSC). METHODS: Cultures of MAPC and MSC were established in parallel from same samples of human bone marrow (n = 5). Both stem cell types were evaluated for expression of pluripotency markers including Oct-4 and Nanog by immunocytochemistry and reversetranscription polymerase chain reaction (RT-PCR) and expression of standard mesenchymal markers including CD14, CD34, CD44, CD45, CD73, CD90, CD105 andhuman leukocyte antigen (HLA)-ABC by flow cytometry. After treatment with neural induction medium both MAPC and MSC were evaluated for expression of neural proteins [neuronal filament-200 (NF-200) and glial fibrillar acidic protein (GFAP)] by immunocytochemistry and Western blotting and neural genes [NF-200, GFAP, Tau, microtubule-associated protein (MAP)-1B, MAP-2, neuron-specific enolase (NSE) and oligodendrocyte-1 (Olig-1)] by quantitative real-time-PCR. RESULTS: MAPC had small trigonal shaped while MSC had elongated spindle-shaped morphology. The MAPC expressed Oct-4 and Nanog both at gene and protein levels, whereas MSC were negative for these pluripotent markers. MAPC were negative for HLA-ABC while MSC had high expression of HLA-ABC. In addition, MAPC as compared to MSC had significantly lower expression of CD44 (36.56% ± 1.92% vs 98.23% ± 0.51%), CD73 (15.11% ± 2.24% vs 98.53% ± 2.22%) and CD105 (13.81% ± 3.82%vs 95.12% ± 5.65%) (P < 0.001, for all) MAPC cultures compared to MSC cultures treated with neural induction medium had significantly higher fold change expression of NF-200 (0.64), GFAP (0.52), Tau (0.59), MAP-2 (0.72), Olig-1 (0.18) and NSE (0.29) proteins (P < 0.01 for Olig-1 and P < 0.001 for rest) as well as higher fold change expression of genes of NF-200 (1.34),GFAP (1.12),Tau (1.08),MAP-1B (0.92), MAP-2 (1.14) andNSE (0.4) (P < 0.001 for all). CONCLUSION: MAPC can be differentially characterized from MSC as Oct-4 and Nanog positive stem cells with no expression of HLA-ABC and low expression of mesenchymal markers CD44, CD73 and CD105 and when compared to MSC they possess greater predilection for differentiation into neuro-ectodermal lineage.

Triple-modal imaging of stem-cells labeled with multimodal nanoparticles, applied in a stroke model

BACKGROUND Mesenchymal stem cells(MSCs) have been widely tested for their therapeutic efficacy in the ischemic brain and have been shown to provide several benefits. A major obstacle to the clinical translation of these therapies has been the inability to noninvasively monitor the best route, cell doses, and collateral effects while ensuring the survival and effective biological functioning of the transplanted stem cells. Technological advances in multimodal imaging have allowed in vivo monitoring of the biodistribution and viability of transplanted stem cells due to a combination of imaging technologies associated with multimodal nanoparticles(MNPs) using new labels and covers to achieve low toxicity and longtime residence in cells.AIM To evaluate the sensitivity of triple-modal imaging of stem cells labeled with MNPs and applied in a stroke model.METHODS After the isolation and immunophenotypic characterization of human bonemarrow MSCs(hBM-MSCs), our team carried out lentiviral transduction of these cells for the evaluation of bioluminescent images(BLIs) in vitro and in vivo. In addition, MNPs that were previously characterized(regarding hydrodynamic size, zeta potential, and optical properties), and were used to label these cells,analyze cell viability via the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and BLI analysis, and quantify the internalization process and iron load in different concentrations of MNPs via magnetic resonance imaging(MRI),near-infrared fluorescence(NIRF), and inductively coupled plasma-mass spectrometry(ICP-MS). In in vivo analyses, the same labeled cells were implanted in a sham group and a stroke group at different times and under different MNP concentrations(after 4 h or 6 d of cell implantation) to evaluate the sensitivity of triple-modal images.RESULTS hBM-MSC collection and isolation after immunophenotypic characterization were demonstrated to be adequate in hBM samples. After transduction of these cells with luciferase(hBM-MSCLuc), we detected a maximum BLI intensity of 2.0 x10^8 photons/s in samples of 10~6 hBM-MSCs. Analysis of the physicochemical characteristics of the MNPs showed an average hydrodynamic diameter of 38.2 ±0.5 nm, zeta potential of 29.2 ± 1.9 mV and adequate colloidal stability without agglomeration over 18 h. The signal of iron load internalization in hBM-MSCLuc showed a close relationship with the corresponding MNP-labeling concentrations based on MRI, ICP-MS and NIRF. Under the highest MNP concentration, cellular viability showed a reduction of less than 10% compared to the control.Correlation analysis of the MNP load internalized into hBM-MSCLuc determined via the MRI, ICP-MS and NIRF techniques showed the same correlation coefficient of 0.99. Evaluation of the BLI, NIRF, and MRI signals in vivo and ex vivo after labeled hBM-MSCLuc were implanted into animals showed differences between different MNP concentrations and signals associated with different techniques(MRI and NIRF; 5 and 20 μg Fe/mL; P < 0.05) in the sham groups at 4 h as well as a time effect(4 h and 6 d; P < 0.001) and differences between the sham and stroke groups in all images signals(P < 0.001).CONCLUSION This study highlighted the importance of quantifying MNPs internalized into cells and the efficacy of signal detection under the triple-image modality in a stroke model.

人胎儿真皮间充质干细胞对人恶性黑色素瘤细胞增殖、迁移、侵袭的抑制作用观察

目的 观察人胎儿真皮间充质干细胞(FDMSCs)对人恶性黑色素瘤细胞(A375细胞)增殖、迁移、侵袭的抑制作用。方法 通过酶消化法从16~20孕周的人意外流产健康胎儿的背部皮肤中提取FDMSCs,并进行鉴定。选取A375细胞并分为3组,F-CM组加入FDMSCs条件培养基,A-CM组加入成人真皮成纤维细胞条件培养基,Control组加入DMEM低糖空白培养基,利用CCK-8细胞增殖实验、划痕细胞迁移实验、细胞侵袭实验测算各组细胞相对活力、细胞迁移率、侵袭细胞数。结果 FDMSCs可以从人胎儿皮肤中成功提取并体外培养,阳性表达间充质干细胞(MSCs)特异性标记CD44、CD90、CD105及胚胎组织特异性标记SSEA-4、OCT-4,且具备成脂、成骨、成软骨的多向分化能力。与Control组比较,F-CM组细胞相对活力下降,细胞迁移率低,侵袭细胞数少(P均<0.05)。结论 FDMSCs可抑制A375细胞的增殖、迁移和侵袭。

人骨髓间充质干细胞通过YAP影响人脂肪肉瘤SW872细胞的生物学行为

目的:观察人骨髓间充质干细胞(hMSCs)条件培养基(CM)与人脂肪肉瘤SW872细胞共培养后对肿瘤细胞增殖和迁移能力的影响,探讨hMSCs CM对脂肪肉瘤细胞的作用及可能的作用机制。方法:体外培养hMSCs,采用慢病毒方法分别转染慢病毒空载体shNS(对照组)和慢病毒shRNA Yes相关蛋白(YAP)(shYAP-hMSCs组),采用实时荧光定量PCR(RT-qPCR)法和Western blotting法检测各组hMSCs中YAP mRNA和蛋白表达水平,提取CM。体外培养SW872细胞,分为对照组(正常培养)、hMSCs CM组和shYAP-hMSCs CM组。采用CCK-8法检测各组细胞增殖活性,流式细胞术检测各组细胞凋亡率,细胞划痕实验检测各组细胞划痕愈合率,Western blotting法检测各组细胞中YAP、基质金属蛋白酶9(MMP-9)和细胞周期蛋白D1(cyclin D1)蛋白表达水平。结果:与对照组比较,shYAP-hMSCs组hMSCs中YAP mRNA和蛋白表达水平降低(P<0.01),表明成功构建了shYAP-hMSCs稳定转染细胞株。CCK-8法,与对照组比较,hMSCs CM组SW872细胞增殖活性升高(P<0.05),shYAP-hMSCs CM组SW872细胞增殖活性降低(P<0.01);流式细胞术,与对照组比较,hMSCs CM组SW872细胞凋亡率无明显变化(P>0.05),shYAP-hMSCs CM组SW872细胞凋亡率升高(P<0.01);细胞划痕实验,与对照组比较,hMSCs CM组SW872细胞划痕愈合率升高(P<0.05),shYAP-hMSCs CM组SW872细胞划痕愈合率降低(P<0.01);Western blotting法,与对照组比较,hMSCs CM组SW872细胞中YAP、MMP-9和cyclin D1蛋白表达水平差异无统计学意义(P>0.05),shYAP-hMSCs组SW872细胞中YAP、MMP-9和cyclin D1蛋白表达水平降低(P<0.05或P<0.01)。结论:hMSCs参与调控人脂肪肉瘤SW872细胞增殖和迁移,其机制可能与YAP表达有关。

人甲床来源的脱细胞支架搭载骨髓间充质干细胞向指甲干细胞分化的研究

目的探究人甲床来源的脱细胞支架搭载骨髓间充质干细胞向指甲干细胞分化的作用。方法收集2022年至2023年在承德医学院附属医院手足外科进行截指术的15例患者的临床废弃甲床组织,制备成脱细胞甲床支架,使用试剂盒检测参照组(未脱细胞组)与脱细胞组(脱细胞甲床支架组)中总胶原蛋白含量、残留DNA含量;将脱细胞甲床支架与人骨髓间充质干细胞(hMSCs)进行共培养14 d。比较对照组(hMSCs组)与共培养组(脱细胞甲床支架+hMSCs组)体外细胞分化能力及指甲干细胞标志物[角蛋白15,角蛋白17,G蛋白偶联受体6(Lgr6)以及β-联蛋白(β-catenin)蛋白]含量。结果脱细胞组总胶原蛋白含量为(189.62±45.45)μg/mg,低于参照组[(196.02±41.93)μg/mg],但两组相比差异无统计学意义(P>0.05);脱细胞组中DNA含量为(0.41±0.15)μg/mg,明显低于参照组[(0.87±0.13)μg/mg],差异有统计学意义(P<0.05)。培养14 d后,共培养组吸光度值为1.09±0.07,对照组吸光度值为1.10±0.5,两组相比差异无统计学意义(P>0.05)。培养14 d后,共培养组角蛋白15、角蛋白17、Lgr6、β-catenin含量分别为(39.56±5.09)、(45.83±4.01)、(5.74±0.99)、(146.79±5.34)pg/mL,均明显高于对照组[(12.10±4.28)、(10.47±3.19)、(0.93±0.67)、(67.28±7.41)pg/mL],差异均有统计学意义(P<0.05)。结论脱细胞甲床支架中的DNA有被清除、保留胶原蛋白,与hMSCs共培养后细胞增殖能力正常,且可诱导hMSCs向指甲干细胞分化,为临床上治疗甲床缺损提供新思路。

慢病毒沉默Piezo1蛋白与人骨髓间充质干细胞成骨分化及TAZ的表达

背景:Piezo1作为机械敏感蛋白与成骨分化密切相关,TAZ也被证明参与调节成骨分化,但Piezo1调控人骨髓间充质干细胞成骨分化时TAZ是否参与其中目前尚不明确,故研究其具体机制对防治股骨头坏死具有重要意义。目的:探讨Piezo1对人骨髓间充质干细胞成骨分化及TAZ表达的影响。方法:构建靶向Piezo1的siRNA,转染至293T细胞,通过RT-qPCR检测其沉默效率并筛选出Piezo1-Homo-2337进行包装,使用荧光染色检测其最佳感染复数值。Piezo1沉默重组慢病毒进一步被转染至人骨髓间充质干细胞中,通过RT-qPCR、Western blot检测其沉默效果;通过茜素红染色、碱性磷酸酶活性分析、免疫荧光染色、RT-qPCR及Western blot检测分析沉默Piezo1对人骨髓间充质干细胞成骨分化能力及TAZ表达的影响。结果与结论:①与正常组、阴性对照组比较,转染si-Piezo1后人骨髓间充质干细胞中Piezo1的mRNA及蛋白水平明显降低;②与阴性对照组比较,si-Piezo1组碱性磷酸酶活性明显降低,钙沉积明显减少;③与阴性对照组比较,si-Piezo1组成骨相关基因Runx2、OPN、DLX5、osteocalcin、β-catenin及TAZ的mRNA水平明显降低。si-Piezo1组TAZ、β-catenin的蛋白表达明显降低;相反,si-Piezo1组p-TAZ、p-β-catenin的蛋白表达明显增加;④与阴性对照组比较,免疫荧光染色结果提示si-Piezo1组人骨髓间充质干细胞中TAZ、β-catenin的表达较少;⑤结果表明Piezo1可促进人骨髓间充质干细胞的成骨分化,沉默Piezo1后人骨髓间充质干细胞的成骨能力明显降低,同时TAZ的表达也同样降低。

LncRNA NEAT1抑制细胞焦亡促进人骨髓间充质干细胞的成骨分化

目的探讨长链非编码RNA(lncRNA)核旁斑组装转录本1(NEAT1)通过调节细胞焦亡调控人骨髓间充质干细胞(hBMSCs)成骨分化的作用。方法培养hBMSCs 7 d诱导细胞成骨分化,并分为对照组(常规培养)、成骨分化组(成骨分化诱导)、pcD-NEAT1组(转染NEAT1过表达质粒)、pcD-null组(转染NEAT1过表达质粒阴性对照)、成骨分化+CML组[成骨分化诱导联合NOD样受体家族蛋白3(NLRP3)炎性小体激活剂(Nε)-羧甲基赖氨酸(CML)处理]、成骨分化+CML+pcD-NEAT1组(成骨分化诱导联合pcD-NEAT1与CML处理)。经茜素红染色检测细胞矿化程度;碱性磷酸酶(ALP)活性检测试剂盒检测ALP活性;CCK-8检测各组细胞存活率,高倍镜下观察细胞形态变化。TUNEL实验检测细胞凋亡率。qRT-PCR检测NEAT1的表达。Western blot检测IL-1β、IL-18、NLRP3、cleaved-caspase 1(cleaved-CASP1)、gasdermin D、Runt-相关转录因子2(RUNX2)、ALP、骨桥蛋白(OPN)的表达。结果与对照组比较,成骨分化组细胞的矿化程度增加,ALP活性升高(P<0.05),NEAT1和RUNX2、ALP、OPN蛋白表达均上调(P<0.05)。与pcD-null组比较,pcD-NEAT1组细胞的矿化程度增加,ALP活性升高(P<0.05),NEAT1和RUNX2、ALP、OPN蛋白表达均上调(P<0.05)。与成骨分化组比较,成骨分化+CML组细胞矿化程度减轻,ALP活性降低(P<0.05),细胞存活率降低(P<0.05),细胞凋亡率增加(P<0.05),细胞膜出现破裂,细胞膨大变形,NLRP3和IL-1β、IL-18、cleaved-CASP1、gasdermin D蛋白表达均显著上调(P<0.05),而RUNX2、ALP、OPN蛋白表达均显著下调(P<0.05)。与成骨分化+CML组比较,成骨分化+CML+pcD-NEAT1组细胞矿化程度增加,ALP活性升高(P<0.05),RUNX2、ALP、OPN蛋白表达均显著上调(P<0.05),细胞存活率增加(P<0.05),细胞凋亡率降低(P<0.05),细胞膜较完整且细胞形态正常,NLRP3和IL-1β、IL-18、cleaved-CASP1、gasdermin D蛋白表达均显著下调(P<0.05)。结论NEAT1过表达通过抑制NLRP3炎性小体介导的细胞焦亡促进hBMSCs的成骨分化。