ObjectiveTo investigate the inhibitory effect of lentivirus-mediated polypyrimidine bundle binding protein-associated splicing factor (PSF) on retinal neovascularization (RNV) in mice model of oxygen-induced retinopathy (OIR).MethodsOne hundred and twelve 5-day-old C57BL/6J mice were randomly divided into normal control group, simple OIR model group, OIR model + lentivirus empty vector treatment group (Vec group) and OIR model + PSF lentivirus treatment group (PSF group), with 16, 32, 32 and 32 mice, respectively. When the mice were 7 days old, the mice in the normal control group were fed in a routine environment, and the mice in the OIR model group, Vec group and PSF group were established OIR model. The mice in the Vec group and PSF group were given an intravitreal injection of 1 μl of lentiviral vector and PSF lentivirus (titer 1×1011 TU/ml) at the age of 12 days. No injection was performed in the normal control group and simple OIR group. RNV was evaluated by counting the number of pre-retinal neovascular cells and analysis of non-perfusion area by immunofluorescent staining of the mouse retina. Real-time quantitative PCR was applied to detect the mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1). Western blot analysis was applied to detect the protein expression of Nrf2, HO-1 and PSF. Results Of the normal control group, simple OIR model group, Vec group and PSF group, the number of pre-retinal neovascular cell nuclei were 0.00, 14.36±5.50, 15.67±4.96, 8.13±2.09, the non-perfusion area were 0.00%, (35.71±2.81)%, (36.57±4.53)%, (15.33±4.75)%, respectively. The differences of the number of pre-retinal neovascular cell nuclei and non-perfusion area among 4 groups were significant (F=24.87, 165.70; P＜0.05). Compared with the normal control group, there were more pre-retinal neovascular cell nucleis and larger non-perfusion area in the simple OIR model group and Vec group (P＜0.05). Compared with the simple OIR model group and Vec group, there were lower pre-retinal neovascular cell nucleis and smaller non-perfusion area in the PSF group (P＜0.05). Real-time quantitative PCR and Western blot showed that the mRNA expression of Nrf2, HO-1 (F=53.66, 83.54) and protein expression of Nrf2, HO-1 and PSF (F=58.38, 52.69, 24.79) among 4 groups were significant (P＜0.05). The mRNA expression of Nrf2, HO-1 and protein expression of Nrf2, HO-1 and PSF in the simple OIR model group and Vec group decreased significantly than those in the normal control group (P＜0.05). The mRNA expression of Nrf2, HO-1 and protein expression of Nrf2, HO-1 and PSF in the PSF group were increased significantly than those in the simple OIR model group and Vec group (P＜0.05). model group and Vec group (P＜0.05).ConclusionIntravitreal injection of lentivirus-mediated PSF inhibits RNV in mice model of OIR possibly through up-regulating the expression of Nrf2 and HO-1.
Objective To construct recombinant lentiviral expression vectors of porcine transforming growth factor β1 (TGF-β1) gene and transfect bone marrow mesenchymal stem cells (BMSCs) so as to provide TGF-β1 gene-modified BMSCs for bone and cartilage tissue engineering. Methods The TGF-β1 cDNA was extracted and packed into lentiviral vector, and positive clones were identified by PCR and gene sequencing, then the virus titer was determined. BMSCs were isolated frombone marrow of the 2-month-old Bama miniature pigs (weighing 15 kg), and the 2nd and 3rd generations of BMSCs wereharvested for experiments. BMSCs were then transfected by TGF-β1 recombinant lentiviral vectors (TGF-β1 vector group)respectively at multi pl icity of infection (MOI) of 10, 50, 70, 100, and 150; then the effects of transfection were detected bylaser confocal microscope and Western blot was used to determine the optimal value of MOI. BMSCs transfected by empty vector (empty vector group) and non-transfected BMSCs (non-transfection group) were used as control group. RT-PCR, immunocytochemistry, and ELISA were performed to detect the expressions of TGF-β1 mRNA, TGF-β1 protein, and collagen type II. Results Successful construction of recombinant lentiviral vectors of porcine TGF-β1 gene was identified by PCR and gene sequencing, and BMSCs were successfully transfected by TGF-β1 recombinant lentiviral vectors. Green fluorescence was observed by laser confocal microscope. Western blot showed the optimal value of MOI was 70. The expression of TGF-β1 mRNA was significantly higher in TGF-β1 vector group than in empty vector group and non-transfection group (P lt; 0.05). Immunocytochemistry results revealed positive expression of TGF-β1 protein and collagen type II in BMSCs of TGF-β1 vector group, but negative expression in empty vector group and non-transfection group. At 21 days after transfection, high expression of TGF-β1 protein still could be detected by ELISA in TGF-β1 vector group. Conclusion TGF-β1 gene can be successfully transfected into BMSCs via lentiviral vectors, and long-term stable expression of TGF-β1 protein can be observed, prompting BMSCs differentiation into chondrocytes.
ObjectiveTo obtain rat hair follicle stem cells (rHFSCs) which can constantly and highly express vascular endothelial growth factor 165 (VEGF165), and to observe the expression of VEGF165 gene in rat HFSCs. MethodsThe cirri skin of 1-week-old Sprague Dawley rat was harvested and digested by using combination of Dispase and type IV collagenases. The bulge was isolated under microscope. The rHFSCs were cultured by tissue block method. After purified by rapid adhering on collagen type IV, the growth curve of different generations rHFSCs was drawn. The cells were identified by immunofluorescence staining and real time quantitative PCR (RT-qPCR) analysis that tested the expression level of correlated genes. Lentivirus of pLV-internal ribosome entry site (IRES)-VEGF165-enhanced green fluorescent protein (EGFP) (experimental group) and pLV-IRES-EGFP empty vector (control group) was packaged by calcium transfected method and the rHFSCs were transfected. The green fluorescent protein expression was observed by inverted fluorescence microscope, and VEGF165 mRNA and protein expressions were detected using RT-PCR and Western blot. ResultsThe rHFSCs which were isolated, cultured, and purified were like the "slabstone", and had strong adhesion ability and colony formation ability. The purified cells were in latent growth phase at 2-3 days; they were in exponential growth phase at 5-6 days. The expressions of cytokeration 15 (CK15), integrin α6, and integrin β1 (markers of HFSCs) were positive by immunocytochemistry. The RT-qPCR analysis showed that CK15, CK19, integrin α6, and integrin β1 expressed highly, but CD34 (a marker of epidermal stem cells) and CK10 (a marker of keratinocyte) expressed lowly. After 14 days, the transfection efficiency was up to 85.76%±1.91%. RT-PCR analysis and Western blot showed that VEGF165 mRNA and protein expressions were positive in experimental group, and were negative in control group. ConclusionThe rHFSCs with high purity and strong proliferation ability can be obtained by using microscope combined with tissue cultivation and rapid cell adhesion on collagen type IV. The rHFSCs with high expression of VEGF165 can be successfully obtained by lentiviral transfection. This method provides good seeding cells for tissue engineering to construct artificial hair follicles, blood vessels, and skins.
ObjectiveTo observe the morphological and functional changes of retinal degeneration in mice with CLN7 neuronal ceroid-lipofuscinosis, and the therapeutic effects of glial cell derived neurotrophic factor (GDNF) and/or ciliary neurotrophic factor (CNTF) based on neural stem cells (NSC) on mouse photoreceptor cells. MethodsA total of 100 CLN7 mice aged 14 days were randomly divided into the experimental group and the control group, with 80 and 20 mice respectively. Twenty C57BL/6J mice aged 14 days were assigned as wild-type group (WT group). Mice in control group and WT group did not receive any interventions. At 2, 4, and 6 months of age, immunohistochemical staining was conducted to examine alterations in the distribution and quantity of cones, rod-bipolar cells, and cone-bipolar cells within the retinal of mice while electroretinography (ERG) examination was utilized to record scotopic a and b-waves and photopic b-wave amplitudes. At 14 days of age, the mice in the experimental group were intravitreally injected with 2 μl of CNTF-NSC, GDNF-NSC, and a 1:1 cell mixture of CNTF-NSC and GDNF-NSC (GDNF/CNTF-NSC). Those mice were then subdivided into the CNTF-NSC group, the GDNF-NSC group, and the GDNF/CNTF-NSC group accordingly. The contralateral eyes of the mice were injected with 2 μl of control NSC without neurotrophic factor (NTF) as their own control group. At 2 and 4 months of age, the rows of photoreceptor cells in mice was observed by immunohistochemical staining while ERG was performed to record amplitudes. At 4 months of age, the differentiation of grafted NSC and the expression of NTF were observed. Statistical comparisons between the groups were performed using a two-way ANOVA. ResultsCompared with WT group, the density of cones in the peripheral region of the control group at 2, 4 and 6 months of age (F=285.10), rod-bipolar cell density in central and peripheral retina (F=823.20, 346.20), cone-bipolar cell density (F=356.30, 210.60) and the scotopic amplitude of a and b waves (F=1 911.00, 387.10) in central and peripheral retina were significantly decreased, with statistical significance (P＜0.05). At the age of 4 and 6 months, the density of retinal cone cells (F=127.30) and b-wave photopic amplitude (F=51.13) in the control group were significantly decreased, and the difference was statistically significant (P＜0.05). Immunofluorescence microscopy showed that the NSC transplanted in the experimental group preferentially differentiated into astrocytes, and stably expressed CNTF and GDNF at high levels. Comparison of retinal photoreceptor nucleus lines in different treatment subgroups of the experimental group at different ages: CNTF-NSC group, at 2 months of age: the whole, central and peripheral regions were significantly different (F=31.73, 75.06, 75.06; P＜0.05); 4 months of age: The difference between the whole area and the peripheral region was statistically significant (F=12.27, 12.27; P＜0.05). GDNF/CNTF-NSC group, 2 and 4 months of age: the whole (F=27.26, 27.26) and the peripheral area (F=16.01, 13.55) were significantly different (P＜0.05). In GDNF-NSC group, there was no statistical significance at all in the whole, central and peripheral areas at different months of age (F=0.00, 0.01, 0.02; P＞0.05). ConclusionsCLN7 neuronal ceroid-lipofuscinosis mice exhibit progressively increasing degenerative alterations in photoreceptor cells and bipolar cells with age growing, aligning with both morphological and functional observations. Intravitreal administration of stem cell-based CNTF as well as GDNF/CNTF show therapeutic potential in rescuing photoreceptor cells. Nevertheless, the combined application of GDNF/CNTF-NSC do not demonstrate the anticipated synergistic protective effect. GDNF has no therapeutic effect on the retinal morphology and function in CLN7 neuronal ceroid-lipofuscinosis mice.
Objective To observe the influences of uncoupling protein 2 (UCP-2) rs660339 variants transfection on cell proliferation and apoptosis of human umbilical vein endothelial cell (HUVEC). Methods Two UCP-2 green fluorescent protein (GFP) lentivirus constructs were created with the rs660339 locus carried C or T (UCP-2C or UCP-2T), respectively. HUVEC were cultured after lentiviral infection of UCP-2C or UCP-2T. The expression of UCP-2C or UCP-2T was detected with real time polymerase chain reaction. Cell proliferation and cell apoptosis were compared among negative control (NC) group, UCP-2T group and UCP-2C group using CCK-8 cell viability and flow cytometry. Western blot and immunostaining were employed to examine the expression of Bcl-2 gene. Results The lentivirus constructs were successfully created. ＞80% of the transfected cells were found to express GFP under fluorescent microscope. The mRNA levels of UCP-2 gene were significantly increased (F=29.183,P=0.001) in the UCP-2T group and UCP-2C group. The CCK-8 assay revealed that on day two (F=15.970,P=0.004), day three (F=16.738,P=0.004), day four (F=5.414,P=0.045) post-infection, UCP-2T and UCP-2C group showed significantly greater proliferation than the NC cells. The apoptotic rate in the UCP-2T and UCP-2C group was significantly lower than NC group (F=277.138,P=0.000), and the apoptotic rate of UCP-2T was significantly lower than that of UCP-2C (P=0.003). The protein levels of Bcl-2 in the UCP-2T and UCP-2C group were significantly greater than that in the NC group (F=425.679,P=0.000), and the Bcl-2 expression of UCP-2T was greater than that of UCP-2C (P=0.002). The Bcl-2 density in the UCP-2T and UCP-2C group were greater than that in the NC group (F=11.827,P=0.008), while there was no difference between UCP-2T and UCP-2C group (P=0.404). Conclusion The variants of UCP-2 rs660339 may influence HUVEC proliferation and apoptosis, and UCP-2T showed a stronger effect of inhibiting apoptosis than UCP-2C.
ObjectiveTo explore the feasibility of co-transduction and co-expression of Nogo extracellular peptide residues 1-40 (NEP1-40) gene and neurotrophin 3 (NT-3) gene into neural stem cells (NSCs).MethodsNSCs were derived from the cortex tissue of Sprague Dawley rat embryo. The experiment included 5 groups: no-load lentiviral vector transducted NSCs (group A), NEP1-40 transducted NSCs (group B), NT-3 transducted NSCs (group C), NEP1-40 and NT-3 corporately transducted NSCs (group D), and blank control (group E). Target genes were transducted into NSCs by lentiviral vectors of different multiplicity of infection (MOI; 5, 10, 15) for different time (24, 48, 72 hours). Fluorescent microscope was used to observe the expression of fluorescence protein and acquire the optimum MOI and optimum collection time. Real-time fluorescence quantitative PCR and Western blot tests were utilized to evaluate the gene expressions of NEP1-40 and NT-3 in NSCs and protein expressions of NEP1-40 and NT-3 in NSCs and in culture medium.ResultsThe optimum MOI for both target gene was 10 and the optimum collection time was 48 hours. The real-time fluorescence quantitative PCR and Western blot results showed that the mRNA and protein relative expressions of NEP1-40 in groups B and D were significantly higher than those in groups A and C (P<0.05), but no significant difference was found between groups B and D, and between groups A and C (P>0.05). The mRNA and protein relative expressions of NT-3 in groups C and D were significantly higher than those in groups A and B (P<0.05), but no significant difference was found between groups A and B, and between groups C and D (P>0.05).ConclusionNEP1-40 and NT-3 gene can be successfully co-transducted into NSCs by the mediation of lentiviral vector. The expressions of the two target genes are stable and have no auxo-action or antagonism between each other.
Objective To observe the effect of shRNA interference lentivirus vector targeting rat Sirt1 gene on the expression of Sirt1 in retinal ganglion cell (RGC). Methods Four short hairpin (sh) RNA interference sequences targeting rat Sirt1 gene were designed. The target sequences of Oligo DNA were synthesized and annealed to double strand DNA, which was subsequently connected with pGLV3 lentivirus vector to build the lentiviral vector. The positive clones were identified by polymerase chain reaction (PCR) and DNA sequencing. The lentiviral vector construct and lentiviral packaging plasmids were co-transfected into 293T cells, then the titer of lentivirus were determined. The RGC were divided into 6 groups including blank group, negative control group and si-Sirt1-1, si-Sirt1-2, si-Sirt1-3, si-Sirt1-4 groups. Real-time PCR and Western blotting were used to detect the expression of Sirt1 mRNA and protein in the RGC cells. Results PCR and DNA sequencing analysis confirmed that the shRNA sequence was successfully inserted into the lentivirus vector. The concentrated titer of virus suspension was 8×108 TU/ml after the recombinant lentiviral vector successfully transfected and harvested in 293T cells. Comparing with NC group, the expression of Sirt1 mRNA and protein were significantly decreased in the si-Sirt1-1, si-Sirt1-2, si-Sirt1-3 and si-Sirt1-4 groups (F=27.682, 1 185.206; P=0.000, 0.000). The si-Sirt1-2 group had the strongest effect in reducing the expression of Sirt1 mRNA and protein. Conclusion The 4 lentiviral vectors harboring RNAi targeting rat Sirt1 gene can effectively down regulate the expression of Sirt1 mRNA and protein in RGC cells.
This study aims to construct the recombinant lentivirus vector containing specific small interfering RNA (siRNA) targeting rat CREB binding protein(CBP)gene and to identify its function of inhibiting the expressions of acetylated histone in primarily cultured hippocampal neurons. Firstly, we constructed four kinds of recombinant lentivirus siCBP. And then we used them to infect the primarily cultured hippocampal neurons, and performed real-time PCR, western blot respectively to detect the expressions of CBP. Afterwards, the most effective lentivirus siCBP was used to infect the primarily cultured hippocampal neurons, and then the HAT activity and protein expressions of acetylated histone Ac-H3, Ac-H4 of the neurons were examined. By using PCR, endonuclease cutting and gene sequencing, we confirmed that the target genes were correctly cloned in lentivirus vector. Besides, CBP mRNA and protein expressions in neurons were found to be with varying degrees of decreases after infections of the four kinds of lentivirus siCBP. Furthermore, the representative and most effective lentivirus GR806 could effectively inhibit the HAT activity and the protein expressions of Ac-H3, Ac-H4 in neurons. It provides the experimental basis for the subsequent application of siCBP to clarify the effects and corresponding molecular mechanism of the CBP-dependent histone acetylation on learning and memory function in hippocampus.
ObjectiveTo discuss the possibility of constructing injectable tissue engineered adipose tissue, and to provide a new approach for repairing soft tissue defects.MethodsHuman adipose-derived stem cells (hADSCs) were extracted from the lipid part of human liposuction aspirate by enzymatic digestion and identified by morphological observation, flow cytometry, and adipogenic induction. The hADSCs underwent transfection by lentivirus vector expressing hepatocyte growth factor and green fluorescent protein (HGF-GFP-LVs) of different multiplicity of infection (MOI, 10, 30, 50, and 100), the transfection efficiency was calculated to determine the optimum MOI. The hADSCs transfected by HGF-GFP-LVs of optimal MOI and being adipogenic inducted were combined with injectable fibrin glue scaffold, and were injected subcutaneously into the right side of the low back of 10 T-cell deficiency BALB/c female nude mice (transfected group); non-HGF-GFP-LVs transfected hADSCs (being adipogenic inducted) combined with injectable fibrin glue scaffold were injected subcutaneously into the left side of the low back (untransfected group); and injectable fibrin glue scaffold were injected subcutaneously into the middle part of the neck (blank control group); 0.4 mL at each point. Twelve weeks later the mice were killed and the implants were taken out. Gross observation, wet weight measurement, HE staining, GFP fluorescence labeling, and immunofluorescence staining were performed to assess the in vivo adipogenic ability of the seed cells and the neovascularization of the grafts.ResultsThe cultured cells were identified as hADSCs. Poor transfection efficiency was observed in MOI of 10 and 30, the transfection efficiency of MOI of 50 and 100 was more than 80%, so the optimum MOI was 50. Adipose tissue-like new-born tissues were found in the injection sites of the transfected and untransfected groups after 12 weeks of injection, and no new-born tissues was found in the blank control group. The wet-weight of new-born tissue in the transfected group [(32.30±4.06) mg] was significantly heavier than that of the untransfected group [(25.27±3.94) mg] (t=3.929, P=0.001). The mature adipose cells in the transfected group [(126.93±5.36) cells/field] were significantly more than that in the untransfected group [(71.36±4.52) cells/field] (t=30.700, P=0.000). Under fluorescence microscopy, some of the single cell adipocytes showed a network of green fluorescence, indicating the presence of GFP labeled exogenous hADSCs in the tissue. The vascular density of new-born tissue of the transfected group [(16.37±2.76)/field] was significantly higher than that of the untransfected group [(9.13±1.68)/field] (t=8.678, P=0.000).ConclusionThe hADSCs extracted from the lipid part after liposuction can be used as seed cells. After HGF-GFP-LVs transfection and adipose induction, the hADSCs combined with injectable fibrin glue scaffold can construct mature adipose tissue in vivo, which may stimulate angiogenesis, and improve retention rate of new-born tissue.
The aim of this study was to establish stable expression of human thyroid stimulating hormone receptor (TSHR) α-subunit (hTSHRA) on human embryonic kidney 293T (HEK 293T). HEK 293T cell lines with stable expression of hTSHRA could be used for detecting affinity between hTSHRA and potential TSHR blocking-peptide. We firstly constructed hTSHRA gene into lentiviral vectors GV218. The sequence comparison indicated that we had constructed GV218-hTSHRAA. Western blot demonstrated the 52 kD aim band of hTHSRA on over-expressed HEK 293T cells. GV218-hTSHRA constructions and pHelper were then co-transfected into HEK 293T cells to form packaging plasmid. The HEK 293T cells that stably expressed hTSHRA could also express green fluorescent protein. The titer of lentiviral packaging vector is 2×108 TU/mL with qPCR. The lentiviral packaging vector thereafter was transfected into HEK 293T cells again. The hTSHRA expressed on the HEK 293T cells. Human TSHRA stably expressed on HEK 293T upon continuously passaging. Therefore, we established hTSHRA stable expression on HEK 293T cells by constructing GV218-hTHSR lentiviral packaging vector. It is a useful tool for studying TSHR affinity with anti-thyroid peptide.