Objective: To construct a recombinant lentiviral vector for mouse miR-204 overexpression, and to verify the targeted regulation of miR-204 and DVL3 in silica (SiO(2)) -induced mouse lung epithelial cells (MLE-12 cells) . Methods: In October 2019, the pre-miR-204 gene was amplified from the mouse genome by the polymerase chain reaction (PCR) method. After sequencing, the amplified product was cloned into the pLenti-CMV-EGFP lentiviral vector. The positive clones were identified by PCR screening and sequencing. The miR-204 overexpressed lentiviral vector was transfected into 293T cells, and lentiviral packaging and titer determination were performed. The experiment was divided into SiO(2) control group, virus control group, and miR-204 virus group, and the expressions of miR-204 and DVL3 gene were detected by real-time PCR. Results: The miR-204 lentiviral expression vector Lv-miR-204-5p was constructed and identified correctly by PCR and sequencing, and a virus dilution with a titer of 9.57×10(8) IU/ml was obtained. The results of real-time PCR showed that the expression of miR-204 in MLE-12 cells of the miR-204 virus group was higher than that of SiO(2) control group and virus control group, and the expression of DVL3 gene was lower than that of SiO(2) control group and virus control group, the differences were statistically significant (P<0.05) . Conclusion: Overexpression of miR-204 by lentiviral vector may inhibit the expression of DVL3 gene in silica-induced mouse lung epithelial cells.
Animals ; Epithelial Cells ; Genetic Vectors ; Lentivirus/metabolism* ; Lung ; Mice ; MicroRNAs/metabolism* ; Silicon Dioxide/toxicity* ; Transfection

Spermatogonial stem cells (SSCs) transmit genetic information to the next progeny in males. Thus, SSCs are a potential target for germline modifications to generate transgenic animals. In this study, we report a technique for the generation of transgenic rats by in vivo manipulation of SSCs with a high success rate. SSCs in juvenile rats were transduced in vivo with high titers of lentivirus harboring enhanced green fluorescent protein and mated with wild-type females to create founder rats. These founder rats expressed the transgene and passed on the transgene with an overall success rate of 50.0%. Subsequent generations of progeny from the founder rats both expressed and passed on the transgene. Thus, direct modification of SSCs in juvenile rats is an effective means of generating transgenic rats through the male germline. This technology could be adapted to larger animals, in which existing methods for gene modification are inadequate or inapplicable, resulting in the generation of transgenic animals in a variety of species.
Animals ; Green Fluorescent Proteins ; Lentivirus ; Male ; Rats ; Rats, Transgenic ; Spermatogonia/metabolism*

OBJECTIVETo construct a recombinant lentiviral vector (pXZ208-BDDhFVIII) mediating B-domain-deleted human coagulation factor VIII (BDDhFVIII) gene and investigate its expression in HLF, Chang-Liver and MSC cells.

METHODSBDDhFVIII gene fragment was separated by endonuclease digestion and was cloned into the multiple cloning sites of pXZ208 to construct a recombinant lentiviral vector pXZ208-BDDhFVIII. Viral particles were prepared by means of three-plasmid cotransfection of 293T package cells by calcium phosphate precipitation. After infection, the coagulant activity of human FVIII in the culture medium of 293T, HLF, Chang-Liver and MSC cells was assayed by one-stage method. The gene transduction efficiency was assayed by flow cytometry (FCM). Furthermore, PCR was performed to test the integration of BDDhFVIII.

RESULTSThe infection rates of HLF, Chang-Liver and MSC were (74.52 +/- 7.57)%, (27.24 +/- 6.53)% and (42.34 +/- 5.84)% respectively. The activities of FVIII in supernatants of HLF, Chang-Liver and MSC were (54.1 +/- 5.6)%, (22.5 +/- 2.9)% and (12.5 +/- 2.7)% respectively. BDDhFVIII gene integration was detected in all the infected cells.

CONCLUSIONThe recombinant lentiviral vector pXZ208-BDDhFVIII was successfully constructed and efficiently integrated into target cells to express human FVIII activity in vitro.

Cell Line ; Factor VIII ; biosynthesis ; genetics ; metabolism ; Gene Expression ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; Plasmids ; Transfection

OBJECTIVETo construct microRNA-223 overexpression and suppression lentivirus vectors and determine their effects after infecting oral squamous cell carcinoma (OSCC) cell line.

METHODSLentivirus vectors GV229 and GV232 were cut by the restriction sites of Age I and EcoR I and connected to the target gene, which contained mature microRNA-223 and microRNA-223 oligonucleotide. Real-time polymerase chain reaction (PCR) method was used to detect the microRNA-223 expression level after infecting the recombinant lentivirus vector into the OSCC cell line.

RESULTSThe successful construction of microRNA-223 recombinant lentivirus vectors was confirmed by the PCR method and DNA sequencing. HN-30 cell infected with microRNA-223 overexpression vector showed a significant increased in microRNA-223 expression, whereas HN-30 cell infected with microRNA-223 inhibitor vector suppressed microRNA-223 expression.

CONCLUSIONThe microRNA-223 overexpression and suppression lentivirus vectors are successfully constructed. These vectors could alter the expression level of microRNA-223 in OSCC cell line significantly, and provide a stable cell line for functional studies in the future.

Base Sequence ; Cell Line, Tumor ; Genetic Vectors ; Humans ; Lentivirus ; MicroRNAs ; metabolism ; Real-Time Polymerase Chain Reaction

OBJECTIVEThe effects of lentivirus-mediated suppression of Cyclin Y (CCNY) expression on the proliferation of laryngeal cancer cells were investigated in vitro.

METHODSThe lentivirus vectors containing a small hairpin RNA (shRNA) to target CCNY were constructed.Hep-2 cells were divided into the following two experimental groups:the negative control group (control lentivirus infected cells) and CCNY knockdown group (CCNY shRNA-expressing lentivirus infected cells). After Hep-2 cells were infected, Real-time PCR was used to measure CCNY expression. The influence of CCNY on the proliferation of laryngeal cancer cells were assessed using MTT and colony formation experiments.Each experiment was performed in triplicate and repeated three times.

RESULTSLentiviruses expressing shRNA against CCNY were constructed and Hep-2 cells were infected with above mentioned lentivirus at MOI (Multiplicity of infection) of 120.Real-time PCR analysis showed that the mRNA expression of CCNY in Hep-2 cells in the knockdown group was significantly decreased (P < 0.05); the mRNA level of CCNY was 75.3% lower in the si-CCNY group than in the si-CTRL group. After 5 days of lentiviral infection, the cell viability was significantly lower in cells infected with the CCNY-shRNA lentivirus compared to cells infected with the control lentivirus following a 6-day incubation. The colony number was decreased by 60% in Hep-2 cells infected with the CCNY-shRNA-lentivirus infected cells following a 10-day incubation.

CONCLUSIONSThe results suggested that lentivirus-mediated downregulation of CCNY expression decreased the proliferation and growth potency of laryngeal cancer cells.Lentiviruses delivering shRNA against CCNY may be a promising tool for laryngeal cancer therapy.

Cell Line, Tumor ; Cell Proliferation ; Cyclins ; Humans ; Laryngeal Neoplasms ; metabolism ; Lentivirus ; genetics ; RNA, Small Interfering ; genetics

This research aims to construct a lentiviral expression vector carrying the extracelluar domain (ED) of human hepatocyte growth factor receptor (C-Met), and to express it in transfected 293T cells. The extracellular domain of C-Met was amplified by RT-PCR, ligated with lentiviral expression vector p RRL-CMV-ED, and then expressed in 293T cell line. The expressed protein was purified and identified by RT-PCR and Western blot. The enzyme digestion and sequence analysis showed that the lentiviral expression vector p RRL-CMV-ED was constructed correctly. The size of amplified genes was about 2 700 bp. The purified protein with Ni-affinity column was about 105 kD analyzed by SDS-PAGE. The Western blot and ELISA results showed that the expressed protein which could bind to HGF specifically was the extracelluar domain of human hepatocyte growth factor receptor. This research may lay a foundation for further study of anti-C-MET monoclonal antibody and neutralizing antibody.
Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; Proto-Oncogene Proteins c-met ; genetics ; metabolism ; Transfection

This study was aimed to construct a lentiviral vector carrying human coagulant factor VIII (FVIII) and to investigate its expression in 293T cells. B-domain-deleted factor VIII gene fragment (BDDhFVIIIcDNA) was obtained by enzyme digestion and cloned into lentiviral vector pXZ208 to establish the expression vector pXZ208-BDDhFVIII. Recombinant viral particles were prepared by cotransfection with packaging plasmid delta NRF and envelope plasmid VSV-G using calcium phosphate precipitation method. 293T cells were transfected by viral supernatant. Coagulant activity of FVIII, BDDhFVIIImRNA and genome integration were assayed by one-step method, RT-PCR and PCR after transfection. The results showed that 293T cells could be transfected by recombinant virus. The transfection rate of 293T was 59.57%. After transfection, the cells expressed FVIII efficiently. Detection confirmed that the activity of FVIII was 12%, 43% and 87% respectively at 24, 48 and 72 hours after infection. BDDhFVIII transcription was detected by RT-PCR from the infected cells. The gene integration in the targeted cells was also observed. It is concluded that the successfully constructed lentiviral vector is able to generate high level expression of human FVIII in 293T cells, which may provide a potential application of gene therapy to haemophilia A.
Cell Line ; Factor VIII ; genetics ; metabolism ; Gene Expression ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; metabolism ; Recombinant Proteins ; genetics ; metabolism

OBJECTIVETo investigate the protective mechanism of stearoyl-CoA desaturase 1 (SCD1) over-expression against the pro-apoptotic affects of palmitic acid on hepatocytes using the rat BRL cell line.

METHODSConcentration effect curves were generated using the trypan blue exclusion test to assess the death rate of BRL cells upon exposure to a dilution series of palmitic acid. The multiplicity of infection (MOI) of a lentiviral expression vector, pGC-FU-GFP, was determined for the BRL cells. Unmanipulated BRL cells were divided into two groups: the non-palmitate groups were composed of ordinary cultured cells (CON) alone, infected with lentivirus empty expression vector (negative control, NC), and infected with lentivirus overexpressing SCD1 (SCD1-LV); the palmitate groups were composed of ordinary cultured cells plus palmitate (CON+) alone, infected with lentivirus empty expression vector plus palmitate (NC+), and infected with lentivirus overexpressing SCD1 plus palmitate (SCD1-LV+). SCD1 mRNA expression was detected by real-time PCR. Propidium iodide (PI) single-staining was used to detect apoptosis and assess the cell cycle. Inter-group differences were analyzed statistically.

RESULTSThe death rate of BRL cells increased significantly after 72 h of exposure to 400 mumol/L palmitate (P less than 0.01). The MOI of pGC-FU-GFP in BRL cells was 20. The expression of SCD1 was significantly higher in the SCD1-LV and SCD1-LV+ groups than in the respective controls (vs. CON: F = 289, P less than 0.01; vs. CON+: F = 1522, P less than 0.01). Palmitate exposure led to decreased expression of SCD1 (CON+ vs. CON, F = 22, P less than 0.05 and NC+ vs. NC: F = 34, P less than 0.05). The ratio of S stage cells was similar in all non-palmitate groups (CON, NC and SCD1-LV, P = 0.137). However, there was a significant apoptotic peak and lower ratio of S stage cells in the control palmitate groups (CON+ and NC+) and the activity of cell proliferation was decreased as well. The ratio of apoptotic cells was decreased significantly in the SCD1-LV+ group compared to the CON+ group (P less than 0.01).

CONCLUSIONThe expression of SCD1 and its desaturation activity increased in BRL cells upon infection with the pGC-FU-SCD1-GFP lentiviral vector, suggesting that SCD1 over-expression can decrease palmitic acid-induced toxicity and apoptosis in hepatocytes.

Animals ; Apoptosis ; Cell Line ; Genetic Vectors ; Hepatocytes ; metabolism ; Lentivirus ; genetics ; Palmitic Acid ; toxicity ; Rats ; Stearoyl-CoA Desaturase ; metabolism

To construct the lentiviral RNA interference (RNAi) vector of rat CXCR4 gene, three target sequences were selected according to rat CXCR4 mRNA sequence, the complementary DNA contained both sense and antisense oligonucleotides were designed and synthesized. After phosphorylation and annealing, these double-strand DNA were cloned to Bgl II and Hind III sites of pSUPER. Then the product pRiCXCR4 was confirmed by electrophoresis and sequencing. Next, CXCR4 shRNA was cloned to a transfer vector of lentivirus, pNL-EGFP, and pNL-RiCXCR4-EGFP was produced. It was confirmed by digestion and sequencing that CXCR4 shRNA expression structure was correctly cloned to pSUPER and pNL-EGFP respectively. Three plasmids, pNL-RiCXCR4-EGFP, pHELPER and pVSVG were cotransfected into 293T to package lentivirus particles. The functional titer of obtained virus was determined by flow cytometry after transduction in 293T, the resulting functional titer of unconcentrated virus and concentrated virus were 6.4 x 10(4) TU/mL and 6.9 x 10(6) TU/mL respectively. After the rat mesenchymal stem cells (rMSCs) were transduced with the constructed lentiviral vectors, real-time RT-PCR, Western blotting and flow cytometry were used to evaluate the level of CXCR4 expression. Compared with control group, the CXCR4 mRNA expression were obviously suppressed in all three experimental groups (rMSCs-CXCR4a, rMSCs-CXCR4b, rMSCs-CXCR4c), especially the expression rate in rMSCs-CXCR4b group was reduced by 95.6%. The RNAi lentivirus vector of rat CXCR4 gene has been constructed successfully. This greatly facilitates the further studies such as evaluation the role of CXCR4 in rMSCs recruitment to damaged tissue.
Animals ; Genetic Vectors ; Green Fluorescent Proteins ; genetics ; metabolism ; Lentivirus ; genetics ; metabolism ; Mesenchymal Stromal Cells ; metabolism ; RNA Interference ; RNA, Small Interfering ; genetics ; Rats ; Receptors, CXCR4 ; genetics ; metabolism ; Transduction, Genetic

OBJECTIVETo observe the influence of infection of murine chemokine receptor-7 recombinant lentivirus on the immunogenicity and migration of dendritic cell strain DC 2.4 cells.

METHODSDC 2.4 cells were routinely cultured. Lentiviruses carrying GFP and those with up-regulated CCR7 were constructed. DC 2.4 cells were divided into DC 2.4 group (without any treatment), GFP-DC 2.4 group (infected with GFP-carrying lentivirus), and CCR7-DC 2.4 group (infected with CCR7-carrying lentivirus labeled by GFP) according to the random number table. The expressions of surface molecules MHCII, CD80, CD86, and CCR7 were detected by flow cytometry, Western blotting, and confocal laser scanning microscope. The migration of cells was detected by chemotaxis assay in vitro. The immunogenicity of cells was detected with mixed lymphocyte reaction. LPS-DC 2.4 group was set up as positive control. Data were processed with one-way analysis of variance and t test.

RESULTSLentiviruses carrying stably-expressing CCR7 were constructed, and the transfection rate of which into DC 2.4 cells was 87.4%. There was no statistically significant difference among DC 2.4, GFP-DC 2.4, and CCR7-DC 2.4 groups in the expressions of MHC II, CD80, and CD86 as showed by flow cytometry (with F values from 0.17 to 1.19, P values all above 0.05). The protein expression of CCR7 of cells in CCR7-DC 2.4 group (45.1 ± 2.1) was obviously higher than that in DC 2.4 and GFP-DC 2.4 groups (25.3 ± 1.4, 28.6 ± 0.9, F = 162.90, P < 0.01), while the difference of which between DC 2.4 group and GFP-DC 2.4 group was not statistically significant (t = 2.20,P > 0.05). The fluorescence intensity of CCR7 in CCR7-DC 2.4 group was obviously increased compared with that of DC 2.4 group. The chemotaxis migration rate of cells in CCR7-DC 2.4 group with the influence of CCL19 was (41.0 ± 2.0)%, which was significantly higher than that of DC 2.4 and GFP-DC 2.4 groups [(6.0 ± 0.5)%, (6.8 ± 0.3)%, F = 84.21, P < 0.01]. There was no statistically significant difference between DC 2.4 group and GFP-DC 2.4 group in the migration rate (t = 0.45, P > 0.05). The absorbance values in DC 2.4, GFP-DC 2.4, CCR7-DC 2.4, and LPS-DC 2.4 groups were respectively 1.6 ± 0.4, 1.9 ± 0.4, 1.7 ± 0.4, 3.8 ± 0.4, and the differences among the former three groups were not obvious (F = 1.56, P > 0.05). The absorbance value in LPS-DC 2.4 group was obviously higher than that of the other three groups (with t values from 1.53 to 1.82, P values all below 0.01).

CONCLUSIONSDC 2.4 cells infected with efficiently CCR7-expressing lentivirus showed high chemotaxis to CCL19, but without obvious change in immunogenicity.

Animals ; Cell Line ; Cell Movement ; Dendritic Cells ; cytology ; immunology ; Lentivirus ; genetics ; Mice ; Receptors, CCR7 ; genetics ; metabolism ; Transfection