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.
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.
Objective To study the feasibility of core-binding factor α1 (Cbfa1) gene modified marrow mesenchymal stem cells (MSCs) composed with porcine acellular bone extracellular matrix in repairing the radial defects. Methods Radial defects of 1.2 cm in length were created in 40 Japanese white rabbits and they were divided into four groups. In group A, MSCs isolated from homogeneous rabbits were infected with Cbfa1 recombinant adenovirus and implanted into acellular bone exteracellular matrix, and then the complexes were implanted into defects. In group B, the complexes including the MSCs without Cbfa1 gene-modified and scaffoldmaterial were implanted into defects. In group C, only the scaffold material was implanted. In group D, defects were not treated as the control. The macroscopic, X-ray and histologic analysis were performed to evaluate the repair effect at 4, 8 and 12 weeks postoperatively. The repaired radius were examined by biomechanical test at 12 weeks postoperatively. Results By gross examination，mature hard new bone formed at grafted areas at 12 weeks postoperativelyin group A, osteotomized ends connected by much callus in group B and less callus in group C at grafted areas. In contrast, bone nonunion formed in group D. X-ray and histological examination showed that the repaired results of defects in the group A were better than those in others groups evidently in extracellular matrix degradation, new bone remodeling and marrow cavity rebuilding at 4 and 8 weeks postoperatively. At 12 weeks postoperatively, the cortical bone became mature lamellar bone, new bone remolding was complete and marrow cavity was smooth in group A. Only proximal end of defects showed that marrow cavity was remolded partially in group B. The continuous callus could be observed in bone defect, and no obvious marrow cavity remolding was observed in group C. Lots of fibrous connective tissue filled in defect and bone nonunion was shown in group D. There was no significant difference in the damage compress loading of repaired radius between groups A, B and D (Pgt;0.05), but there was significant difference between groups C and D(Plt;0.01).Conclusion These results demonstrate that Cbfa1 gene modified MSCs combined with acellular bone extracellular matrix can be used to repair rabbit radial defects.
【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 identify glial cell line-derived neurotrophic factor (GDNF) recombinant retroviral vector and to establish its packaging cell line PA317. Methods PA317 cells were transfected with recombinant retroviral vector pLXSN-GDNF using liposomes. The recombinant retroviral particles were then harvested from culture media of G418 resistant transfected cells and analyzed using RT-PCR. Virus titers in supernatants were investigated. Results Sequencing date indicated that GDNF gene was exactly identical to the sequence in the GeneBank. PA317 cells were transfected with recombinant retroviral vector pLXSN-GDNF using liposomes, and virus titers insupernatants harvested from culture media of G418 resistant transfected cells were 104-105 CFU/ml. Conclusion Packaging cell line PA317/pLXSN-GDNF was established.
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 To observe the the inhibitory effect of recombined adenovirus mediated delivery of p21 (rAd-p21) on oxygen-induced retinal neovascularization in mice. Methods A total of 56 C57BL/6 mice at the age of seven days were divided into control group, phosphate buffer solution (PBS) group, rAd-p21 group and rAdno purpose gene control (rAd-NC) group, 14 mice in each group. The retinal neovascularization of PBS, rAd-p21and rAd-NC group were induced by oxygen, and received an intravitreal injection 1 mu;l PBS, rAd-p21 and rAd-NC at postnatal day 11, respectively.The rats of control group were not intervened. At postnatal day 17,RNV was determined by retinal flat mounts and retinal section; non-perfusion areas of retina were analyzed by Image-Pro plus 6.0 software; reverse transcription-polymerase chain reaction (RT-PCR) and Western blot was used to measure the mRNA and protein expression of p21 and CDK2. Results Compared with PBS and rAdNC groups, the retinal nonperfusion areas, neovascularization and the numbers of endothelial cell nuclei breaking through the internal limiting membrane in rAd-p21 group were reduced significantly. Nonperfusion areas of retina in rAd-p21 group was less than that in PBS and rAd-NC groups, the difference among these three groups was significantly (F=101.634，P＜0.05). Compared with the other three groups, the level of p21 mRNA and protein in rAd-p21 group increased significantly (F=839.664, 509.817;P＜0.05); the level of CDK2 mRNA and protein in rAd-p21 group decreased significantly (F=301.858, 592.882;P＜0.05). Conclusion rAd-p21can inhibit oxygen-induced retinal neovascularization, up-regulated p21 expression and down-regulated CDK2 expression may be the mechanism.
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 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.
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.