Immunotherapy is becoming an effective and less invasive strategy that can be applied to the treatment of various malignancies. Lentiviral vectors (LVs) have shown great potential in immunotherapy as they can stably integrate relatively large foreign DNA, and effectively transduce dividing and non-dividing cells. Clinical application needs high quality LVs, and therefore strict quality control of the final products is necessary to ensure their purity, efficacy and safety. The quantitative detection of LVs is among the key parts of product development and quality control. In this paper, the existing methods for quantitative detection of LVs are summarized, including fluorescence activated cell sorter (FACS), P24 enzyme-linked immuno sorbent assay (P24 ELISA), real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing(TRPS) and virus counter(VC).Their advantages and disadvantages are listed, and future development and challenges are discussed.
Genetic Vectors/genetics* ; Humans ; Immunotherapy ; Lentivirus/genetics* ; Neoplasms ; Transduction, Genetic

Animals ; Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; Rats

Gene therapy has been considered as one of the optimal treatments. Although, at the beginning of this century, a series of unexpected side effects brought gene therapy into depression, the improved lentiviral vectors, which characterised by high efficiency transfection, stable expression in target cells and good biosafety, have been applied in clinical trials in recent years and acquired a certain clinical improvements. Nowadays gene therapy becomes an eye-catching field. This review discusses the gene therapy how blocked by lentiviral vectors, the high efficiency and biosafety of lentiviral vectors, the improvement of lentiviral vector preparation and so on.
Animals ; Genetic Therapy ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; Transfection

In order to study the potential of Venus, lentiviral vector, applied to acute myeloid leukemia, the recombinant vector Venus-C3aR was transfected into 293T packing cells by DNA-calcium phosphate coprecipitation. All virus stocks were collected and transfected into HL-60, the GFP expression in HL-60 cells was measured by flow cytometry. The expression level of C3aR1 in transfected HL-60 cells was identified by RT-PCR and flow cytometry. The lentiviral toxicity on HL-60 was measured by using CCK-8 method and the ability of cell differentiation was observed. The results indicated that the transfection efficacy of lentiviral vector on HL-60 cells was more than 95%, which meets the needs for further study. C3aR1 expression on HL-60 cells increased after being transfected with recombinant lentiviral vector. Before and after transfection, the proliferation and differentiation of cells were not changed much. It is concluded that the lentiviral vector showed a high efficacy to transfect AML cells and can be integrated in genome of HL-60 cells to realize the stable expression of interest gene. Meanwhile, lentiviral vector can not affect HL-60 cell ability to proliferate and differentiate.
Genetic Vectors ; HL-60 Cells ; Humans ; Lentivirus ; genetics ; Transfection

OBJECTIVETo construct a lentiviral RNA interference system targeting heparanase (HPSE) based on miR30 and to test its silencing effect.

METHODSThree heparanase-shRNA structures were designed based miR30. The targeting fragments were obtained by PCR, then inserted into the vector LV PP-GFP to construct the recombinant lentiviral vector LV PP-GFP/miR-HPSE-shRNA, which was identified by PCR and sequencing. The 293T cells were co-transfect with LV PP-GFP/miR-HPSE-shRNA, pHelper 1.0 vector and pHelper 2.0 vector to produce lentiviruses, with which A375 cells were infected. Real-time fluorescence quantitative PCR and Western blot were performed to evaluate the expression of heparanase RNA and protein.

RESULTSThe lentiviral miR30-based RNAi vector targeting heparanase was constructed and confirmed by PCR and sequencing. The results of real-time fluorescence quantitative PCR and Western blot showed that the expression levels of both heparanase mRNA and protein in infected A375 cells were decreased significantly than those in control group.

CONCLUSIONThe lentiviral miR30-based RNAi vector targeting heparanase was been constructed successfully, which can be used for further study on RNAi-mediated oncolytic viruses.

Genetic Vectors ; Glucuronidase ; genetics ; Lentivirus ; genetics ; MicroRNAs ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics

Cell Line, Tumor ; Gene Expression ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; Lipase ; genetics ; Membrane Proteins ; genetics

This study was aimed to establish a high-throughput luciferase reporter system, through which to screen and identify miRNAs directly targeting p21, and to explore the biological function and significance of these miRNAs. Molecular cloning technique was used to construct and identify two lentivirus-expressing vectors-pWPXL-Luc and pWPXL-Luc-P21-3'UTR, virus particles were collected after the pWPXL-Luc or pWPXL-Luc-P21-3'UTR vectors were co-transfected with the psPAX2 packaging plasmid and the envelope plasmid pDM2G into HEK-293T cells. Furthermore, two stable cell lines expressing luciferase singly or co-expressed luciferase and P21-3'UTR were established by transducing HEK-293 cells with recombinant lentivirus; the former was used as control in the following experiments. Finally luciferase activity of the latter stable cells was measured by using the luciferase reporter assay system. The results showed that high-titre recombinant lentivirus was produced and two stable cell lines were constructed, also to some certain, the luciferase activity was in direct proportion to the number of cells. In conclusion, the high-throughput luciferase reporter system is established successfully; using this system, the 28 miRNA that directly target P21 Cip1/Waf1 are screened experimentally.
Genes, Reporter ; Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; Luciferases ; genetics ; MicroRNAs ; genetics ; Plasmids ; Transduction, Genetic

OBJECTIVETo construct a lentiviral expression vector of has-miR-338-3p and verify its target gene.

METHODSThe pre-miR-338-3p was synthesized and inserted into pLV-THM, and the recombinant plasmid pLV-THM-miR-338-3p was confirmed by restriction endonuclease analysis and DNA sequencing. 293T cells were co-transfected with the lentiviral vector pLV-THM-miR-338-3p, psPAX2 and pMD2.G, and the supernatant containing the lentivirus particles was harvested to determine the virus titer and used to infect SW-620 cells. Flow cytometry was employed for sorting the GFP-positive cells. The expression of miR-338-3p was determined using real-time RT-PCR and the expression of SMO protein was detected with Western blotting in the infected SW-620 cells. The invasiveness of the infected SW-620 cells was assessed using Transwell assay.

RESULTSRestriction enzyme digestion and DNA sequencing demonstrated successful construction of the lentiviral vector pLV-THM-miR-338-3p. SW-620 cells infected with pLV-THM-miR-338-3p showed a significantly increased expression of miR-338-3p, and the overexpression of miR-338-3p suppressed the expression of SMO protein and the invasiveness of the cells.

CONCLUSIONThe successful construction of the lentiviral vector pLV-THM-miR-338-3p and the establishment of a SW-620 cell line with miR-338-3p overexpression provide the basis for further study of the molecular function of miR-338-3p in colorectal carcinoma. MiR-338-3p can suppress SMO gene expression to inhibit the invasiveness of colorectal carcinoma cells.

Cell Line, Tumor ; Gene Expression ; Genetic Vectors ; Green Fluorescent Proteins ; genetics ; Humans ; Lentivirus ; genetics ; MicroRNAs ; genetics

OBJECTIVETo construct and identification of a lentiviral vector for RNA interference (RNAi) targeting STUB1 gene.

METHODSA pair of complementary small hairpin RNA (shRNA) oligonucleotides targeting STUB1 gene was designed, synthesized and inserted into linearized pMagic 4.0 vector. The recombinant plasmid was identified by double restriction digestion with Age I/EcoR I and DNA sequencing.

RESULTPCR and DNA sequencing showed that the shRNA sequence was successfully inserted into pMagic 4.0 vector. The pMagic 4.0 vector was successfully packaged into lentivirus particles.

CONCLUSIONA lentiviral shRNA expression vector and particles targeting STUB1 gene has been successfully constructed for the further study of the STUB1 gene.

Gene Targeting ; Genetic Vectors ; Lentivirus ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics ; Ubiquitin-Protein Ligases ; genetics

The aim of study was to establish the packaging system of the recombinant lentiviral vector encoding Gfi1 gene for eukaryotic expression and to realize the efficient, stable expression of Gfi1 32D cells so as to provide effective platform for further studying the development of Gfi1 gene in hematologic malignancies. The three-plasmid recombinant lentiviral vector consisting of transfer plasmid (pLOX-Gfi1/pLOX), the packaging plasmid (pCMVDeltaR8.2) and the envelop plasmid (pMD.G) was prepared and purified. Human embryonic kidney 293T cells were cotransfected with the three plasmids by lipofectamine 2000. After transfection for 48 hours, the viral supernatant was collected and the target cell 32D was transfected with the recombinant lentivirus; the Gfi1 integration and expression in 293T and 32D cells were detected by Western-blot. The results showed that the three plasmids of lentivirus could be transfected into 293T with high efficiency and packaged successfully, and the Gfi1 protein could be detected by fluorescent microscopy. The recombinant lentiviruses carrying Gfi1 could transfer and deliver Gfi1 gene to 32D cells, and the Gfi1 expression in 293T and 32D cell could be detected by Western blot. It is concluded that the recombinant lentivirus carrying Gfi1 can deliver target gene to 32D cells with high efficiency, and the expression of Gfi1 protein is stable in 32D.
Cell Line ; DNA-Binding Proteins ; genetics ; Genetic Vectors ; Humans ; Lentivirus ; genetics ; Plasmids ; Transcription Factors ; genetics ; Transfection