ObjectiveTo elucidate whether hypoxia induced factor-1α (HIF-1α) gene improved hypoxia tolerant capability of bone marrow mesenchymal stem cells uptake(MSCs) or not and whether the capability was related to glucose uptake increase in hypoxia MSCs ex vivo or not. MethodsMSCs were randomly divided into normoxia non-HIF-1α transfection group (control group), normoxia HIF-1α transfection group, hypoxia non-HIF-1α transfection group, and hypoxia HIF-1α transfection group and then each group was cultured with normoxia (5% CO2 at 37 ℃) or hypoxia (94% N2, 1% O2, 5% CO2 at 37 ℃) for 8 h, respectively. Finally, the expressions of HIF-1α were detected by immunocytochemistry, RT-PCR, and Western blot methods, respectively. Apoptosis ratio (AR) and death ratio (DR) were tested by flow cytometry. The proliferation was detected by MTT method. Glucose uptake was assayed by radiation isotope method. Results① Compared with the normoxia non-HIF-1α transfection group, the expression of HIF-1α mRNA significantly increased (Plt;0.01) in the normoxia HIF-1α transfection group except for its protein (P=0.187); Both of mRNA and protein expressions of HIF-1α in the hypoxia HIF-1α transfection group were significantly higher than those in the hypoxia non-HIF-1α transfection group (Plt;0.01). ② The AR (P=0.001) and DR (P=0.003) in the hypoxia HIF-1α transfection group were significantly lower thanthose in the hypoxia non-HIF-1α transfection group, both of which were significantly higher than those in the normoxia non-HIF-1α transfection group (Plt;0.01). ③ The proliferation of MSCs in the hypoxia HIF-1α transfection group was significantly higher than that in the hypoxia non-HIF-1α transfection group (P=0.004), which significantly lower than that in the normoxia non-HIF-1α transfection group (P=0.001). ④ Compared with the hypoxia non-HIF-1α transfection group, the 3H-G uptake capability (P=0.004) of MSCs significantly increased in the hypoxia HIF-1α transfection group, which was significantly lower than that in the normoxia non-HIF-1α transfection group (P=0.001). ⑤ There were significantly negative relation between AR and HIF-1α protein (r=－0.71，P=0.005) or 3H-G uptake (r=－0.65，P=0.004), and significantly positive relation between HIF-1α protein expression and 3H-G uptake (r=0.77, P=0.003). ConclusionHIF-1α gene significantly improves anti-hypoxia capability of MSCs, which is fulfilled by increasing glucose upake.
Objective To investigate the effect s of T lymphoma invasion and metastasis inducing factor 1 ( Tiam 1) antisense oligonucleotides (ASODN) on morphological remodeling of gast ric cancer cells. Methods The high-invasive and metastastic subgroup (MH ) was separated f rom human gast ric cancer cell line MKN245 (M0 ) by laminin adhesion method in vi t ro. And they were divided into four group s according to different further t reatment s : no t ransfection group (cont rol group ) , liposome t ransfection group , sense oligonucleotides2liposome t ransfection group ( SODN t ransfection with liposome group ) and antisense oligonucleotides2liposome t ransfection group (ASODN t ransfection with liposome group) . Then the expressions of Tiam 1 mRNA and protein were detected by RT-PCR and flowcytomet ry , respectively. The morphology changes between Tima 1 ASODN t ransfected MH cells and no t ransfected cells were observed by using HE stain , cytoskeletal protein stain and scanning elect ronic microscope (SEM) . Results Compared with the other group s , the expressions of Tiam 1 mRNA and protein in MH cells were significantly decreased af ter the cells were t ransfected with 0. 43 μmol/ L Tiam 1 ASODN ( P lt; 0. 01) . Additionally , it was observed that the t ransfected MH cells had less membrane surface projections , fewer or shortener pseudopodia , less irregular cytoskeletal network and less spotted-like actin bodys than no t ransfected MH cells did. Conclusion ASODN t ransfection could effectively suppress the expression of Tiam 1 and the remodeling in gast ric cancer cells , which may play an important role in the invasion and metastasis of gast ric cancer cells.
ObjectiveTo evaluate the most efficient method for transfection of human umbilical cord mesenchymal stem cells (HUMCSs) in vivo. MethodsHUCMSCs were isolated from human umbilical cord and cultured, which were labelled by PKH26 and lentivirus-GFP, then were observed by using a fluorescence microscope. Sixty SD rats were randomly divided into PKH26 transfection group and lentivirus-GFP transfection group. The right hepatic lobe of rat was resected, then the transfected stem cells were injected into portal vein. The rats were sacrificed on day 3, 8, and 13 after transfection. The liver specimens were observed by using a fluorescence microscope. Flow cytometry was used to evaluate the percentage of transfected stem cells and the apoptotic stem cells. ResultsThe third generation of HUCMSCs labelled by PKH26 and lentivirus-GFP were spindle shaped. PKH26 red dye was evenly distributed in the cell membrane of HUCMSCs and could be clearly labelled. The HUCMSCs labelled by lentivirus-GFP were green fluorescence under the fluorescence microscope, and it was clear and stable. The HUCMSCs were clear and could be clearly distinguished on day 3 after transfection by two methods in vivo. As the time went by, red was faded and blurred, then was gradually disappeared on day 13 after transfection in the HUCMSCs stansfected by PKH26; but the color in the HUCMSCs stansfected by lentivirus-GFP were clear at all the time points. The transfection rate of the lentivirus-GFP was significantly higher that that of the PKH26 (P < 0.05), the rate of apoptotic stem cells had no significant differences at all the time points between these two groups (P > 0.05). ConclusionLentivirus-GFP transfection is a higher efficient method for stem cell labelling in vivo, it could be used to observe transplantation cells for a long time in future.
ObjectiveTo determine the optimizing parameters in transfecting the SV-40-PED cells mediated by oligofectamine. Methods With a change of Decoy oligodeoxynucleotides(ODNs)/oligofectamine in ratio and the transfection time, the uptake rate and the mean fluorescence intensity of SP1 ODNs in the SV-40-PED cells were measured by flow cytometry to evaluate the transfection efficiencies. 4 μl oligofectamine with different concentrations of ODNs(2.5，5.0，7.5，10.0 and 12.5 μl) were put into 100 μl of DMEM without serum and antibiotics. the (SV-40-PED) cells were transfected after 20 min at room temperature. the final concentration of SP1 decay ODNs were 50，100，150，200 and 250 nmol/L. Transfection effieiency was detected at 26 h after transfection. The intracellular distribution ofSP1 ODNs was determined with a fluorescence microscope. The lactate dehydrogenase (LDH) activity in the supernatant was measured to assess the cytotoxicity.Results The uptake of SP1 ODNs into the SV-40-PED cells was significantly improved by oligofectamine. The cell appearance did not change much in the groups of 50, 100 and 150 nmol/L. In the groups of 200 and 250 nmol/L, the cell reverted after being shrinked and altered to round. At 26 h after the transfection, there was no marked change in the cell form at the concentration of 250 nmol/L. There was floatation at 48 and 72 h after the transfection. Under the fluorescence microscope, we observed fluorescent materials distributed in the cell nucleus in the successfully-transferred groups. We could see the nucleoli clearly in the groups of 200 nmol/L and 250 nmol/L. There was a ber fluorescence intensitywith a higher concentration and the fluorescent materials gathered at the cell nucleus. At the final concentration of 250 nmol/L, the LDH level was 137.12±3.92 U/L in the 72hgroup, which was significantly higher those that in the 26h group（49.61±17.13 U/L）and the 48h group（120.26±8.42 U/L）(Plt;0.01). At 26 h after the transfection, there were no statistical differences at the above LDHlevels in the different-concentration groups（Pgt;0.05）. Conclusion Transfection efficiency is the highest when the final concentration of the SP1 decoy ODNs is 250 nmol/L during the incubation of for 24 h in transfecting the SV-40-PED cells.
ObjectiveTo observe the inhibitory effect of lentivirus mediated small interference RNA (siRNA) targeting cyclic adenosine monophosphate responsive element binding protein 1 (CREB1) on retinal neovascularization (RNV) in mice. MethodsCREB1 siRNA construct was created, screened and packaged to produce CREB1 RNAi-lentivirus. One hundred and forty (5-day-old) C57BL/6J mice were randomly divided into 4 groups including normal group, oxygen induced retinopathy (OIR) group, empty vector group and CREB1 therapy group with 35 mice in each group. Mice in the normal group were kept in normal room air, while in the other three groups retinal neovascularization was induced by hypoxia on postnatal day 7 (P7). The mice in the OIR group were not treated. The mice in the vector group received intravitreal injection of lentivirus-green fluorescent protein (lenti-GFP, 1 μl), and the CREB1 therapy group received CREB1 RNAi-lentivirus (1 μl) on P5.The proliferative neovascular response was quantified by counting the vascular cell nuclei extending breaking through the internal limiting membrane (ILM) and fluorescent angiography. The areas of RNV and non-perfusion region were calculated. The expression of CREB1, phosphorylated-CREB1 (P-CREB1) and vascular endothelial growth factor (VEGF)-A levels, Akt and phosphoinositide 3-kinases (PI3K) in retinas were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot. ResultsThe number of vascular cell nuclei breaking through the ILM of the OIR group and the empty vector group increased significantly compared with the normal group (P<0.05), while obviously decreased in the CREB1 therapy group compared with the OIR group and the empty vector group(P<0.05). The area of RNV and non-perfusion region of the OIR group and the empty vector group increased significantly compared with the normal group, while obviously decreased in the CREB1 therapy group compared with the OIR group and the empty vector group. The difference of area of RNV and non-perfusion region among 4 groups were significant (F=67.220, 110.090; P<0.05). The mRNA expression of CREB1 and protein expression of P-CREB1, the mRNA and protein expression of VEGF-A, Akt, PI3K in the retina were increased significantly in the OIR group and the empty vector group as compared with the normal group, while decreased significantly in the CREB1 therapy group as compared with the OIR group and the empty vector group. The difference of mRNA expression of CREB1, VEGF-A, Akt, PI3K in the retina among 4 groups were significant (F=6.087, 5.464, 6.191, 8.627; P<0.05). The protein expression of P-CREB1, VEGF-A, Akt, PI3K in the retina among 4 groups were significant (F=162.944, 13.861, 19.710, 22.827; P<0.05). ConclusionRNV in the mice is significantly inhibited by intravitreal injection of lentivirus-mediated CREB1 down-regulation.
Objective To study the transfection and expression of pleiotrophin (Ptn) gene in mice adipose-derived stem cells (ADSCs) so as to provide a new approach for the treatment of ischemic injury. Methods ADSCs from clean inbred C57BL/6W mice (weighing, 15-20 g) were isolated and cultured in vitro. The cell surface markers (CD29 and CD44) of ADSCs were identified by flow cytometry. The ADSCs were transfected with plasmid pIRES2-LEGFPN1 (containing Ptn gene coding sequence) as experimental group (group A) and with plasmid pLEGFP-N1 (containing GFP gene coding sequence) as control group (group B). After ADSCs were transfected by different plasmids respectively, the cells containing Ptn gene were selected by G418 (the best selected concentration was 200 μg/mL), and the immunophenotype of the cells was identified by flow cytometry after transfection. Meanwhile, real-time fluorescence quantitative PCR and Western blot were used to analyse the expression levels of Ptn mRNA and PTN protein in selected cells. Results The mice ADSCs were isolated and cultured successfully in vitro. The positive rates of the cell surface markers CD29 and CD44 of ADSCs were 99.5% and 95.8%, respectively; the double positive rate of CD44 and CD29 was 93.6%. The positive rates of the cell surface markers CD29 and CD44 of ADSCs were 99.1% and 95.6%, respectively after transfection of Ptn gene; the double positive rate of CD44 and CD29 was 93.4%. The expression levels of Ptn gene and PTN protein in group A were significantly higher than those in group B (P lt; 0.05). Conclusion The ADSCs can be stablely transfected by Ptn gene, the transfected ADSCs can express PTN protein highly, which is a new idea for tissue engineering of vascular reconstruction.
Objective To investigate the expression of micro-dystrophin gene in myoblast cultured in vitro, to explore the possibil ity of combining myoblast transplantation with gene transfer for Duchenne muscular dystrophy therapy. Methods Competent Escherichia coli JM109 was prepared, which transformed with plasmid pSL139, and positive clones were picked to cultivate. Plasmid was extracted with Alkal ine lysis method and cutted with both Pvu I and Cla I enzyme. Agarose gel electrophoresis was employed to take pictures. Ten healthy 5-7 days old male C57/BL10 mice were selected, weighing4-5 g, the primary and subcultured myoblasts were cultured with multi-step enzymatic digestion and differential adhesionmethod, and Desmin immunofluorescent method was used to identfy. The 3rd generation myoblasts that were transfected with plasmid pSL139 mediated by l iposome served as the experimental group, untransfected cells served as the control group. After 48 hours of transfection, the expressions of micro-dystrophin mRNA and protein in myoblasts were detected with RTPCR and cell immunofluorescent methods, and the transfection efficiency was caculated. Results After pSL139 plasmids being digested and for 40 minutes agarose gel of electrophoresis, 3.75 kb fragment of target gene and vector were observed. The cells were almost uniform, and triangular or diamond shape after 24-48 hours of culture; the cells turned to fusion manner and could be passaged after 4-6 days. Desmin immunofluorescent result showed that green fluorescence was seen in cytoplasm of most 2nd myoblasts, and the purity of the myoblasts was above 90%. At 48 hours after transfection of myoblasts with plasmid pSL139, RT- PCR results showed that about 300 bp fragment was seen in the experimental group and the control group, and the brightness was higher in experimental group. Immunofluorescent staining displayed that green fluorescence was seen in the cytoplasm of the myoblasts in the experimental group and no green fluorescence in the control group; the expression efficiency of positive cells for micro-dystrophin was 45%-55% in experimental group. Conclusion Micro-dystrophin gene can highly express at the levels of mRNA and protein respectively in myoblasts transfected with plasmid pSL139 mediated by l iposome.
Objective According to heparanase’s gene sequence of GenBank, to construct heparanase gene-targeted small interfering RNA (siRNA) and its expression vector and to observe its interference effect on the expression of heparanase gene in human malignant breast cancer MDA-MB-231 cell. Methods Heparanase gene-targeted hairpin siRNA was designed, two complementary oligonucleotide strands were synthesized and inserted into pGPU6/GFP/Neo vector, which was identified by sequence identify. Human malignant breast cancer MDA-MB-231 cell was transfected with the constructed vector with lipofectamine method. Fluorescence photograph was taken. Real-time PCR (RT-PCR) was performed to evaluate the level of heparanase mRNA expression. Results Four kinds of heparanase gene-targeted hairpin siRNA were designed, then were inserted into pGPU6/GFP/Neo vector after annealing. Sequencing indicated the construction was successful. Fluorescence photographs showed MDA-MB-231 cells were transfected successfully. RT-PCR showed that heparanase mRNA expression levels were inhibited significantly （Plt;0.05）. Conclusion The heparanase gene-targeted siRNA and its vector are successfully constructed and MDA-MB-231 cells are transfected successfully. Heparanase mRNA expression levels are significantly inhibited by siRNA vector, which provide a new method for the treatment of cancer.
ObjectiveTo investigate the bone regeneration potential of cell-tissue engineered bone constructed by human bone marrow mesenchymal stem cells (hBMSCs) expressing the transduced human bone morphogenetic protein 2 (hBMP-2) gene stably. MethodsThe full-length hBMP-2 gene was cloned from human muscle tissues by RT-PCR and connected into a vector to consturct a eukaryotic expression system. And then the gene expression system was transduced to hBMSCs with lipidosome. hBMSCs were transfected by hBMP-2 gene (experimental group) and by empty plasmid (negative control group), untransfected hBMP-2 served as blank control group. RT-PCR, dot-ELISA, immunohistochemical analysis and ALP activity were performed to compare and evaluate the situation of hBMP-2 expression and secretion after transfection. hBMSCs transfected by hBMP-2 gene were seeded on hydroxyapatite (HA) and incubated for 4 days to construct the hBMP-2 gene modified tissue engineered bone, and then the tissue engineered bone was observed by the inverted phase contrast microscope and scanning electron microscope. Then the hBMP-2 gene modified tissue engineered bone (group A, n=3), empty plasmid transfected hBMSCs seeded on HA (group B, n=3), hBMSCs suspension transfected by hBMP-2 gene (group C, n=3), and hBMP-2 plasmids and lipidosome (group D, n=3) were implanted into bilateral back muscles of nude mice. The osteogenic activity was detected by HE staining and alcian blue staining after 4 weeks. ResultsAt 48 hours and 3 weeks after transfection, RT-PCR and dot-ELISA results indicated that the transfected hBMSCs could express and secrete active and exogenous hBMP-2 stably. The immunohistochemical staining was positive, and the ALP activity in the transfected hBMSCs was significantly higher than that in two control groups (P < 0.05). The transfected hBMSCs had a good attaching and growing on the three-demension suface of HA under inverted phase contrast microscope and scanning electron microscope. In vivo study indicated that a lot of new bone formation was obviously found at 4 out of 6 sides of back muscles in group A. Some new bone formation at both sides of back muscles was observed in 1 of 3 mice in group B. No new bone formation was found in group C. A few new bone formation was observed at one side of back muscles in group D. ConclusionThe tissue engineered bone constructed by hBMP-2 gene modified hBMSCs and HA is able to express and secrete active hBMP2 stably and can promote new bone formation effectively in muscles of nude mice.
ObjectiveTo observe the inhibitory effect of lentivirus (LV)-mediated miR-191 on the proliferation and angiogenesis of human retinal vascular endothelial cells (hREC) cultured in vitro.MethodsThe hREC cell lines were cultured in vitro and divided into control group, hypoxia group, LV-empty vector (LV-vector) group, and LV-miR-191 (LV-191) group. The LV-vector group and LV-191 group were transferred to the corresponding lentiviral vector respectively. Flow cytometry was used to detect cell transfection efficiency. Cell Counting Kit-8 (CCK-8) test was used to detect cell proliferation ability. Scarification test and invasion chamber (Transwell) test were used to detect cell migration ability. Matrigel test was used to detect cell lumen formation ability. Real-time quantitative polymerase chain reaction (qPCR) was used to detect the relative expression of miR-191 and relative mRNA expression of its downstream target genes p21, vascular endothelial growth factor (VEGF), cell division protein kinase (CDK) 6, cyclin-D1 (Cyclin D1). Independent sample t test was used for pairwise comparison. ResultsThe results of flow cytometry showed that the transfection efficiency of cells in the control group and the LV-191 group were 0.615% and 99.400%, respectively. The results of CCK-8, scarification, Transwell and Matrigel test showed that, compared with the control group, the number of cell proliferation (t=6.130, 4.606), the cell mobility (t=4.910, 6.702), the number of stained cells on the microporous membrane (t=7.244, 6.724) and the lumen formation ability cells (t=8.345, 9.859) were significantly increased in the hypoxia group and the LV-vector group (P<0.01), while the LV-191 group showed completely opposite performance (t=14.710, 6.245, 5.333, 5.892; P≤0.01). The qPCR test results showed that, compared with the control group and the LV-vector group, the relative expression of miR-191 mRNA in the cells of the LV-191 group was significantly up-regulated (t=44.110, 42.680), the relative expression of Cyclin D1 mRNA (t=29.940, 14.010) and CDK6 mRNA (t=15.200, 7.645) decreased significantly, and the difference were statistically significant (P<0.01); the relative expression of p21 mRNA increased, however, the difference was not statistically significant (t=2.013, 2.755; P>0.05). There was no significant difference in the relative expression of VEGF mRNA in the 4 groups of cells (F=0.966, P>0.05). ConclusionsLV-191 can inhibit the proliferation, migration and tubing of hREC by up-regulating p21 and down-regulating CDK6 and Cyclin D1.