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.
Objective To observe the effects of vascular endothelial growth factor antisense oligonucleotide (VEGF-ASODN) on expression of vascular endothelial growth factor (VEGF) and growth in gastric cancer cells. Methods The VEGF-ASODN was synthesized artificially with phosphorothioic acid. After transfecting with VEGF-ASODN in gastric cancer cells SGC-7901, the initial copy number of mRNA was detected by real-time RT-PCR, and the quantity of VEGF protein in both cell and supernatant were detected by ELISA. The levels of expression of survivin protein in cells were measured by Western blot. FCM and MTT method were used to detect cellular apoptosis and the activity of cells, respectively. The effect of transfection on the growth of cells was evaluated by growth curve. Results The copy number of VEGR mRNA, protein levels of VEGF in the cells and in culture fluid all decreased when the concentration of transfected VEGF-ASODN increased, as well as the levels of survivin protein （P＜0.05）. The ratio of apoptosis increased, the activity of cells also decreased as the concentration of transfected VEGF-ASODN increased （P＜0.05）. Conclusion Transfection with VEGF-ASODN in gastric cancer cells SGC-7901 can inhibit the expressions of VEGF and survivin remarkably. It can enhance cellular apoptosis and suppress growth of cells.
【Abstract】ObjectiveTo study the effect of transfection with antisense DNMT3b gene eukaryotic expression vector on the expression of DNMT3b gene in human cholangiocarcinoma cell line QBC-939. MethodsThe constructed antisense DNMT3b gene eukaryotic expression vector was transfected into the human cholangiocarcinoma cell line QBC-939 by using lipofectamine transfection reagents, and positive cell clones were obtained by using G418 selection after transfection. Whether the constructed recombinant vector was transfected into QBC-939 cells successfully was confirmed by amplifying the exogenous neoR gene with PCR method. The expression of DNMT3b gene mRNA and protein were detected by semi-quantitative RT-PCR and FCM methods respectively. ResultsFollowing the transfection of antisense DNMT3b gene eukaryotic expression vector, the mRNA level of DNMT3b gene in QBC-939 cells of human cholangiocarcinoma decreased from 0.956±0.053 to 0.209±0.023, and the protein level of DNMT3b gene also decreased from (75.38±3.22)% to (29.87±3.46)%. There were very significant differences on the expression levels of DNMT3b gene between non-tranfections group and the antisense DNMT3b gene eukaryotic expression vector transfection group (P＜0.01). ConclusionTransfection with antisense DNMT3b gene eukaryotic expression vector significantly reduces the expression level of DNMT3b gene in human cholangiocarcinoma cell line QBC-939, and this study may provide a valid tool and method to investigate the function of DNMT3b gene and its role in cholangiocarcinoma.
Objective To investigate the effects of recombinant adeno-associated virus type-2 (rAAV2) mediated delivery of pigment epitheliumderived factor (PEDF) on oxygen-induced retinal neovascularization (OIRNV) in mice. Methods A total of 22 C57/BL6 mice at the age of 3 days received intravitreal injections of 1 mu;l rAAV2-PEDF and rAAV2EGFP into the left eyes (experimental group) and the right eyes (control group). All mice were put into the oxygen box right after the injection to induce the OIRNV model.4 mice were sacrificed and PEDF protein in retina was measured by western blot at postnatal days 13 (P13). Twelve mice underwent retinal angiography with high molecular weight fluoresceindextran, and another 6 mice were sacrificed for retinal lectin immunohistochemistry staining at P17. Absolute and relative nonperfusion areas of retinal neovascularization were analyzed by Image-Pro Plus 5.1 software. Results The expression level of PEDF protein was higher in the experimental group than that in the control group.The absolute nonperfusion area was (0.96plusmn;0.22) mm2 in the experimental group and (1.96plusmn;0.34) mm2 in the control group; the difference between the two groups was significant（t=-8.554, P＜0.01）. The relative nonperfusion area was (8.64plusmn;1.52)% in the experimental group and (17.27plusmn;2.98)% in the control group with a significant difference between the two groups (t=-8.97, P＜0.01).The absolute area of retinal neovascularization was (0.37plusmn;0.11) mm2 in the experimental group which was obviously higher than (1.26plusmn;0.38) mm2 in the control group (t=-7.8, P＜0.01); the relative areas in experimental and control groups was (3.96plusmn;0.66)% and (11.45plusmn;2.06)%, respectively, whose difference is apparently(t=-8.51, P＜0.01).The areas of retina neovascularization were (0.11plusmn;0.003) mm2 and (0.41plusmn;0.02) mm2 in the experimental and control groups, respectively, and the difference between the two groups was significant（t=-5.14, P＜0.01）.Conclusions PEDF protein can stably express in the mice retina after rAAV2-PEDF transfetion. rAAV2-PEDF can decrease the retinal non-perfusion areas and inhibit the retinal neovascularization in OIRNV mice.
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.
ObjectiveTo observe the effect of adenovirus-mediated Tum5 (rAd-Tum5) inhibiting retinal neovascularization (RNV) of oxygen-induced retinopathy (OIR) mouse model. MethodsThe OIR model was induced in 96 C57BL/6J mice aged of 7 days according to the literature. These mice were divided randomly into control group, OIR group, OIR rAd-green fluorescent grotein (GFP) group and OIR rAd-Tum5 group, each group had 24 mice. The rAd-GFP and rAd-Tum5 were injected into the vitreous cavity of mice aged of 12 days in OIR rAd-GFP group and OIR rAd-Tum5 group, respectively. Meanwhile, OIR group and the control group received the injection of physiological saline solution of same volume. The relatively non-perfusion area was evaluated by fluorescence angiography, and the number of pre-retinal nucleus breaking through internal limiting membranes was observed by hematoxylin-eosin staining. The expression of vascular endothelial growth factor (VEGF) was estimated by immunofluorescent (IF) and Western blot. ResultsThe retinal avascular areas of all groups were significantly different (F=61.224, P<0.01). The retinal avascular area of the rAd-Tum5 group was decreased significantly comparing with that in the OIR group and rAd-GFP group (P<0.01). However, there are no significant differences between the OIR group and rAd-GFP group (P=0.827). The number of pre-retinal nucleus breaking through ILM of all groups was significantly different (F=635.738, P<0.01), but no significantly difference was observed in OIR group and rAd-GFP group (P=0.261). Significant differences could also been seen between OIR rAd-Tum5 group and OIR group as well as OIR rAd-Tum5 group and OIR rAd-GFP group (P<0.01). The results of IF and Western blot indicated that expression of VEGF in the OIR group and rAd-GFP group was obviously up-regulated, compared with that in the control group. But the expression was declined in the rAd-Tum5 group compared with that in the OIR group and rAd-GFP group. ConclusionTum-5 peptide can efficiently prevent RNV probably by down-regulating expression of VEGF.
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.
Objective To construct a green fluorescent protein expression plasmid pEGFP-C3-anti-TAG72 scFv-CD28, containing anti-TAG72 single chain variable fragment (scFv) fused into the transmembrane and intracellular domain of the signal-transducing chain of CD28 gene, and to transfect it into peripheral blood mononuclear cells． Methods Recombinant transmembrane and intracellular domain of CD28 cDNA and anti-TAG72 scFv cDNA fragment was subcloned into pEGFP-C3 vector. Recombinant clones were selected by Kanamyein， and then identified by PCR， enzyme digestion analysis and DNA sequencing. The recombinant plasmid was transfected into peripheral blood mononuclear cells by means of lipofection. The recombinant protein expression was confirmed by immunocytochemistry, laser scanning confocal microscope, PCR and Western blot analysis. Results The fused gene fragment of anti-TAG72 scFv-CD28 was successfully inserted into pEGFP-C3 plasmid, and it was confirmed by enzyme digestion and DNA sequencing. The fused anti-TAG72 scFv-CD28 gene and its protein was identified in peripheral blood mononuclear cells． Conclusion The eukaryotic expression plasmid pEGFP-C3-anti-TAG72 scFv-CD28 was successfully constructed and transiently expressed in peripheral blood mononuclear cells， which would lay a foundation for further studies on the role of it to activate tumor-associated antigen-specific T lymphocyte, for generating of modified T lymphocytes targeting gastrointestinal tumors.
ObjectiveTo observe the expression in vitro and the influence of adenovirus-mediated recombinant Tum5 gene to the proliferation, migration and tubing of Rhesus RF/6A cell under high glucose. MethodsTo construct the adenovirus vector of recombinant Tum5 gene (rAd-Tum5), and then infected RF/6A cell with it. The Flow Cytometry was used to detect the infection efficiency. RF/6A cells were divided into normal group, high glucose (HG)-control group (HG group), empty expression vector group (HG+rAd-GFP), and HG+rAd-Tum5 group. Western blot was used to detect the expression of Tum5. The CCK-8 test was applied to detect the proliferation of RF/6A cell, the Transwell test was applied to detect the migration and the Matrigel test was applied to detect the tubing of RF/6A cell under high glucose. The proliferation, migration and tubing of RF/6A were tested respectively by CCK-8 test, Transwell test and Matrigel test. ResultsThe adenovirus vector of recombinant Tum5 gene was successfully constructed. The infection efficiency of rAd-Tum5 in RF/6A cell was 50.31% and rAd-GFP was 55.13% by the Flow Cytometry. The results of Western blot indicated that Tum5 was successfully expressed in RF/6A cell. The result of CCK-8 test, Transwell test and Matrigel test indicated that there were statistical differences between all groups in proliferation, migration and tubing of the RF/6A cell (F=44.484, 772.666, 137.696;P < 0.05). The comparison of each group indicated that the HG group was higher than normal group (P < 0.05). There were no statistical differences between HG group and HG+rAd-GFP group (P > 0.05). However, the HG+rAd-Tum5 group was less than HG group (P < 0.05), and the same to HG+rAd-GFP (P < 0.05). ConclusionThe adenovirus vector of recombinant Tum5 gene can inhibit the proliferation, migration and tubing of RF/6A cell under high glucose.