ABSTRACT
Objective@#To develop a real-time quantitative PCR (qPCR) assay for detecting Sendai virus gene copy number.@*Methods@#The recombinant plasmid was constructed and a reference used to establish the real-time qPCR method with the TaqMan probe and verified for reproducibility and sensitivity.@*Results@#The linear range of the developed real-time qPCR assay was 1.024 × 103 ~5 × 1010 copies/μl, with an R2 value of more than 0. 99. The standard recovery of the tested samples was 84.56%~119.48%.@*Conclusions@#Compared with traditional hernagglutination assay for particle number detection, this method has higher sensitivity, better repeatability and high quantitative accuracy. It can be used for the detection of particle number of vaccine with sendai virus as the carrier, so as to detect the specific activity of vaccine products.
ABSTRACT
Objective To construct the recombinant co-expression vector carrying antisense RNA to dual-target BAG-1 and Bcl-2 genes and recombinant single expression vector carrying antisense RNA to target BAG-1 and Bcl-2 gene respectively,then to pre-liminarily investigate their effect on the proliferation of gastric cancer cell SGC-7901 in order to lay the foundation for further study the effect of this recombinant vector on the tumor cells.Methods RT-PCR was used to amplify the full length of BAG-1 and Bcl-2 cDNA from total RNA of gastric cancer cell line SGC-7901.The BAG-1 cDNA fragment and the Bcl-2 cDNA fragment were insert-ed into pMD18-T simple vector respectively.The pMD18-T-BAG-1 was digested with BamH Ⅰ and Cla Ⅰ and the pMD18-T-Bcl-2 was digested with EcoR Ⅰ and Nhe Ⅰ.Then the BAG-1 cDNA fragment and the Bcl-2 cDNA fragment were inserted into the mcs1 and mcs2 of the eukaryotic co-expression vector pVITRO2 in the antisense orientation respectively.The construction of the single expression vector pVITRO2-AsBAG-1 and pVITRO2-AsBcl-2 was confirmed by restriction endonuclease treatment and se-quence identification.Then the Bcl-2 cDNA fragment was inserted into the mcs2 of the recombinant vector pVITRO2-AsBAG-1 in the antisense orientation to construct the co-expression vector pVITRO2-AsBAG-1-Bcl-2,and the recombinant vector was also iden-tified by restriction endonucleases digestion and sequence identification.Then the recombinant vector was transfected into SGC-7901 cell respectively.The proliferation of the cell was determined by the MTT assay.The level change of BAG-1 and Bcl-2 mRNA in SGC-7901 cell was detected by the semi quantitative RT-PCR and the change situation of cell cycle was detected by the flow cytom-etry(FCM).Results The restriction endonucleases digestion and sequencing identification indicated that the eukaryotic co-expres-sion vector pVITRO2-AsBAG-1-Bcl-2 and the single gene expression vector pVITRO2-AsBAG-1 and pVITRO2-AsBcl-2 were con-structed successfully.The MTT assay method demonstrated that compared with the control group,the recombinant vector could in-hibit the proliferation of the cells in time dependent manner,and the inhibiting effect was most notably in the 72 h transfection group(P 0. 05);the FCM detection results showed that the apoptosis rate of the recombinant vector groups was significantly higher than that of the control group and the pVITRO2 group with statistical difference(P <0.01),and the co-expression vector group was more nota-bly than single expression vector groups(P <0.01).In addition,the effect of the co-expression recombinant vector group was more significant than that of the single expression co-expression vector(P <0.01 ),the apoptosis rate was increased from 0.57% to 15.75%.Conclusion The co-expression recombinant vector pVITRO2-AsBAG-1-Bcl-2 and single expression vector pVITRO2-As-BAG-1 and pVITRO2-AsBcl-2 are successfully constructed and they can inhibit the proliferation of SGC-7901 cell and induce cell apoptosis,moreover the pVITRO2-AsBAG-1-Bcl-2 vector is most notably.
ABSTRACT
Background: The aim of this study was to construct a recombinant vector of human sperm specific VDAC3 gene for production of VDAC3 antibody, which is potential as male contraception vaccine. Methods: Target fragment sequence of VDAC3 gene was obtained through amplification of human sperm VDAC3 cDNA with primers covering exon 5 to exon 8. Its PCR product in size of 435 bp was cloned to the pET101/D-TOPO expression vector (5753 bp). E. coli bacteria were transformed with this vector. Cloning of VDAC3 fragment gene to the vector was confirmed by the using of XbaI restriction enzyme and PCR colony method with primers covering exons 5-8 of the human VDAC3 gene. Results: Alignment analysis of amplified fragment covering exon 5 to exon 8 of VDAC3 gene showed 94% homology to human VDAC3 gene from databank. After cloning to the expression vector and transformation to E. coli competent cells, twelve colonies could grow in culture media. Gel electrophoresis of sliced VDAC3 recombinant vector showed a single band in the size of 6181 bp in 8 colonies. After application of PCR colony and amplicon sequencing, the result showed a single band in the size of 435 bp and fragment sequence with 94% identity to human VDAC3 gene. Conclusion: The construction of human sperm specific VDAC3 gene recombinant vector was established in this study. In the future, this recombinant vector will be used to produce VDAC3 antibody for the development of a male contraception vaccine.
Subject(s)
Contraception , Family Planning Services , MenABSTRACT
Objective: To construct and identify the eukaryotic expression vector targeting the CD40 gene in rats.Methods: Two sequences corresponding to the rat CD40 gene were designed on Ambion's Web.The two complementary oligonucleotide strands of DNA fragments were synthesized by chemosynthesis.After annealing of the complementary strands,the DNA fragments were connected to the polyclone sites of the pSilencer 4.1-CMV neo vector,followed by transformation,amplification,plasmid extraction and identification of the recombinant plasmids by BamH Ⅰ and Hind Ⅲ digestion and DNA sequence analysis.Results: The connections between the DNA fragments encoding CD40-targeted siRNA and the pSilencer 4.1-CMV neo vector were correct,as confirmed by agarose gel electrophoresis and DNA sequence analysis.Conclusion: The two recombinant plasmids expressing siRNA of the rat CD40 gene were successfully constructed,which prepared the groundwork for future research on the role of the CD40 gene in homograft rejection.
ABSTRACT
objective In the former research work, a differential-expressed gene was cloned from multi-drug resistance lung cancer cell line (SPC-A-1/CDDP) with suppression substractive hybridization, and in this study we further analyze the site of this gene on the chromosome, and appraise its function related to multi-drug resistance in lung cancer cells. Methods The cDNA sequence data of the gene was input to computer and analyzed to ascertain its site on human chromosome by screening the gen bank on the www.ncbi.nlm.nih.gov. With DNA recombination technique, the gene was reversedly inserted to the vector pLXSN to get an antisense expression recombinant vector pLXSN-R, which was then transfected into SPC-A-1/CDDP cells with the aid of electroporation technique. And the semi-quantitative RT-PCR technique was used to quantify the mRNA content of gene in the transfected cells. Finally, the chemosensitivity of the transfected cells was tested with MTT method. Results The gene was located on the human chromosome 19q13.3-19q13.4 locus. The antisense gene recombinant vector was successfully constructed and transfected into SPC-A-1/CDDP cells as shown by its inhibitory activity on the mRNA expression of the gene. The drug-resistance indexes of transfected SPC-A-1/CDDP cells for cisplatin, doxorubicin, 5-fluorouracil, vincristin, hydroxycamptothecine and etoposide were obviously decreased. Conclusion The function of this gene is related to multi-drug resistance in human lung cancer cell, and its locus on the human chromosome is at 19q13.3-1913.4.
ABSTRACT
Objective:To obtain DNA of human Helicobacter pylori heat shock protein A, and construct a recombinant vector containing gene encoding HspA for nucleotide sequence analysis.Methods:The target gene was amplified from Hp chromosome by PCR, and then digested by restricted endonuclease enzyme of kpn I , BamH I simultanously, and inserted into the prokaryotic expression vector pET32a(+) digested by corresponding restricted endonuclease enzyme. The recombinant vector was selected and transformed for nucleotide sequence analysis.Results:Enzyme digestion analysis and sequencing showed that the target gene had been inserted into recombinant vector, but as compared with gene reported by GenBank. 1.4 % of the gene mutation and 1.6% of amino acid residues change in Hp happened respectively. The DNA sequence analysis showed the sequence of HspA DNA was almost the same as that published by GenBank.Conclusion:The gene coding for Hp HspA is cloned successfully.The results obtained lay the foundation for research on development of Hp protein vaccine and a quickly diagnostic kit applying to detection of Hp infection.