1.Prokaryotic Expression and Functional Study of HIV-1 Envelope Glycoprotein gp41 Helical Bundle
Bin LIU ; Hong-Qiu HE ; Shao-Hui CHENG ; Wei-Zu CHEN ; Cun-Xin WANG ;
China Biotechnology 2006;0(07):-
HIV-1 envelope glycoprotein gp41,which is a hopeful target for HIV-1 fusion inhibitors,plays a critical role in the fusion of viral and cellular membranes.In order to build up the screening assay of HIV-1 fusion inhibitors targeting gp41,HIV-1 gp41 5-helix and 6-helix were expressed in prokaryotic cells.Gp41 5-helix and 6-helix recombined plasmids were constructed by using PCR,enzyme digestion and ligation taking the clade B HIV-1 genome as a template.The plasmid was transferred into E.coli BL21(DE3)and then induced by IPTG.The expressed protein was purified by affinity chromatography after denaturation and renaturation.The SDS-PAGE analysis was used during expression and purification.Native-PAGE was used to identify the interaction between gp41 5-helix and T-20.The result will be helpful to build up the screening assay of HIV-1 fusion inhibitors targeting gp41.
2.Two-Step MS-PCR Combined With ELISA Method for the Detection of Drug Resistance Mutations in HIV-1 RT Gene
Hong-Qiu HE ; Shao-Hui CHENG ; Bin LIU ; Wei-Zu CHEN ; Cun-Xin WANG ;
China Biotechnology 2006;0(08):-
Highly Active Anti-Retroviral Therapy (HAART) has effectively inhibited the prevalence of HIV-1 and reduced the death rate caused by AIDS. In recent years,the emergence of resistance-conferring RT gene mutations in HIV-1 strains has become the major reason for HAART failure. The detection of drug resistance is important for the HAART regimen choice and novel drug development. A novel assay for the detection of HIV-1 RT drug resistance mutations was developed. HIV-1 drug resistance and wild strains in B subtypes were investigated using Two-Step Mutagenically-Separated PCR (MS-PCR),and point mutations including M41L,K70R,K103N,Y181C,T215F were detected. A longer mutant type primer was designed,using microplates hybridization and ELISA technique to detect several point mutations within a mixed mutant-wild type population. The results indicate that the Two-Step MS-PCR is as sensitive and specific as that in the traditional MS-PCR and MS-PCR combined with ELISA can give a good P/N quotient with better sensitivity,low cost,relatively less time consumption and high-throughput screening. It will be used in clinic usage for the detection of HIV-1 drug resistance mutations as well as other point mutations.
3.Prokaryotic Soluble Expression and Functional Study of HIV-1 Integrase Protein
Shao-Hui CHENG ; Xiao-Hui MA ; Hong-Qiu HE ; Bin LIU ; Wei-Zu CHEN ; Cun-Xin WANG ;
China Biotechnology 2006;0(01):-
The pol gene of HIV-1 encodes mainly three enzymes: reverse transcriptase (RT), protease (PR) and integrase (IN). Currently, FDA approved drugs targeting RT and PR are available and administered in various combinations, while no anti-IN drug was approved. HIV-1 integrase is an essential enzyme for the viral replication and an interesting target for the design of new pharmaceuticals for multi-drug therapy of AIDS. The 288 amino acids of IN (32kDa) recognizes specific sequences in the long terminal repeats (LTRs) of the retroviral DNA. The IN protein catalyzes the 3′-processing step and the 5′-strand transfer step reaction in vivo, which was called integration and this reaction could be analysed by ELISA Assay in vitro. It has been reported that F185K and C280S mutations of HIV-1 integrase would improve the enzyme solubility, and the catalytical activity of the enzyme was the same as that of the wild-type enzyme in vitro. In order to build the platform of screening inhibitor against integrase of HIV-1 virus, the IN enzyme was expressed and the function of integrase protein was assayed. The cDNA of clade B HIV-1 genome was used as a template, overlapped PCR was used to construct site mutagenesis of F185K/C280S and NdeI/Xho I restriction sites were brought in. The PCR product was cloned into the prokaryotic vector pET-28a(+) to form a recombined plasmid, transferred into the host cell E.coli(BL21 DE3). The recombined clones were identified by PCR and Nde I/Xho I digestion .The positive plasmid was sequenced, and the successfully recombined plasmid in the host cell was induced by IPTG. The expressed IN protein was puriied sy the Co+ affinity chromatography column and SDS-PAGE was used to analyze the molecular weight and specificity. In addition, ELISA assay was used to analyze the function of the recombined IN protein. The recombinant protein was soluble, and expressed highly and stably in E.coli. The molecular weight of the expression product was identical to the expectation. The IN protein was proved to be functional in 3′ processing and 5′strand transfer by ELISA. It will be helpful to build the platform of screening inhibitors against HIV-1 integrase.
4.Observation of protective effect on mice after immunization with Yersinia pestis capsular antigen F1 and recombinant rV270
Rui-xia, DAI ; Zhi-zhen, QI ; Ling-ling, REN ; Qing-wen, ZHANG ; Cun-xiang, LI ; Rong-jie, WEI ; Hai-lian, WU ; Xiao-yi, WANG ; Zu-yun, WANG
Chinese Journal of Endemiology 2011;30(6):646-648
Objective To evaluate the protective effect of Yersinia pestis capsular antigen F1 and recombinant rV270 on mice after immunization with them.Methods According to body weight,40 female Balb/c mice aged 6 to 8 weeks were randomly divided into four experimental groups(Fl-10 μg + aluminum adjuvant,F1-20 μg + aluminum adjuvant,rV-10 μg + aluminum adjuvant,and rV-20 μg + aluminum adjuvant) and a control group,8 in each group.Mice in experimental groups were immunized with the natural antigen F1 and recombinant antigen rV270 adsorbed to 25% aluminum adjuvant and the control group was immunized with the same amount of aluminum adjuvant.Each mouse was immunized at the hind leg muscle with 100 ml immunizing agent,then a booster immunization was done once on the 21st day after the first immunization.The blood of all mice was collected on the 8th week after the first immunization,serum antibody titers were detected by ELISA and the data of antibody titers were analyzed by t test for comparison between groups.At the same time the mice were injected subcutaneously with 2000-fold LD50 of Yersinia pestis virulent strain 141,after 14 days,the protective effect of immunization was analyzed.Results The control group did not produce antibody.Antibody geometric mean titers (GMT) of the F1-10 mg + aluminum adjuvant and F1-20 mg + aluminum adjuvant groups were 1 ∶ 30443.9,and 1 ∶21527.8,respectively,and compared between the two groups,the difference was not statistically significant (t =1.1282,P > 0.05).The GMTs of the rV-10 μg + aluminum adjuvant and rV-20 μg + aluminum adjuvant groups were 1 ∶ 13957.3 and 1 ∶18100.9,respectively,and compared between the two groups,the difference was not statistically significant(t =0.9408,P > 0.05 ).After subcutaneous injection with Yersinia pestis virulent strain 141,all mice died in the control group but all survived in the experimental group.Conclusion The immune activity of natural antigen F1 and recombinant rV270 is high,which can be used as the main component of subunit vaccine in the plague subunit vaccine study.
5.Nervus cutaneus femoris posterior pedicle flap for repairing large soft tissue defects at the heel or inferior segment of the shank.
Rui-ying WANG ; Jun-zu HU ; Lin-wei XIN ; Ji-cun TANG ; Yan GAO
Chinese Journal of Traumatology 2009;12(5):275-278
OBJECTIVETo investigate the clinical effect of the nervus cutaneus femoris posterior pedicle flap on repairing large soft tissue defects at the heel or inferior segment of the shank.
METHODSTotally 14 cases were followed up for 8-22 months (mean 15.5 months) to observe the clinical effects of nervus cutaneus femoris posterior pedicle flap on repairing large soft tissue defects of the heel or inferior segment of the shank. Among them, there were 3 patients afflicted with infection and cutaneous defects in the middle and inferior segment of the shank after internal fixation of open fracture, 4 patients with soft tissue defects of the ankle and uncovered tendo calcaneus, and 7 patients with soft tissue defects of the heel and exposed calcaneus.
RESULTSThe flaps survived well in 13 cases and partial necrosis occurred in 1 case that was thereafter cured with changing dressing. Various extents of pain and stiffness of the knee joints were present in all cases and disappeared through 1-8 weeks' (mean 3.2 weeks) functional exercises. The last follow-up showed that all the flaps kept good texture and satisfactory appearance.
CONCLUSIONSThe nervus cutaneus femoris posterior pedicle flap, having the advantages of simple surgical procedures, anastomosing the nerves and restoring the sensation of recipient site, can be used for recovering large soft tissue defects of the shank and ankle.
Adolescent ; Adult ; Aged ; Female ; Heel ; surgery ; Humans ; Leg ; surgery ; Male ; Middle Aged ; Soft Tissue Injuries ; surgery ; Surgical Flaps
6.Study on combined gene therapy for malignant gliomas transfected with antisense hTERT/PTEN in vitro and in vivo.
Yong-ping YOU ; Zhen FU ; Peng ZHAO ; Cun-zu WANG ; Ning LIU ; Ai-lin LU
Chinese Journal of Medical Genetics 2006;23(6):605-609
OBJECTIVETo study inhibitory efficacy of combined gene therapy for malignant gliomas transfected with antisense human telomerase reverse transcriptase (hTERT)/PTEN in vitro and in vivo.
METHODSTo construct two adenovirus recons which contained antisense hTERT and wild-type PTEN respectively with high performance homologous recombination system in bacteria. The two adenovirus recons were transfected into U251 human malignant glioma cells combinedly or respectively in vitro and in vivo. U251 cell proliferation in vitro was determined by MTT assay and flow cytometry, tumor growth in vivo was measured by the volume of glioma in nude mice. Telomerase activity was detected by telomeric repeat amplification protocol (TRAP) assay. Expression of hTERT and PTEN protein was detected by Western blotting methods.
RESULTSAfter transfection in vitro, the growth of U251 cells was inhibited significantly. The inhibitory effect was time-dependent. The strongest inhibition was observed in combined transfection group, at the 6th day, the survival rate was 37.6%, telomerase activity (only 28.8TPG) was inhibited significantly, hTERT protein expression was inhibited significantly too, which was 0.2106, but PTEN protein expression was increased significantly, which was 0.9630. In vivo, the growth of tumors was also effectively inhibited.
CONCLUSIONGrowth of malignant glioma cells is effectively inhibited after transfection with combined antisense hTERT and PTEN in vitro and in vivo.
Adenoviridae ; genetics ; Animals ; Apoptosis ; Blotting, Western ; Brain Neoplasms ; pathology ; therapy ; Cell Line, Tumor ; Cell Proliferation ; DNA, Antisense ; genetics ; metabolism ; Flow Cytometry ; Genetic Therapy ; methods ; Glioma ; pathology ; therapy ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Mice ; Mice, Nude ; Microscopy, Fluorescence ; PTEN Phosphohydrolase ; genetics ; Recombinant Fusion Proteins ; genetics ; metabolism ; Telomerase ; genetics ; metabolism ; Transfection ; Tumor Burden ; Xenograft Model Antitumor Assays
7.Effects of acupuncture on Chinese medicine syndromes of vascular dementia.
Guang-xia SHI ; Cun-zhi LIU ; Wei GUAN ; Zhan-kui WANG ; Lei WANG ; Chuan XIAO ; Zu-guang LI ; Qian-qian LI ; Lin-peng WANG
Chinese journal of integrative medicine 2014;20(9):661-666
OBJECTIVETo study the effects of acupuncture on Chinese medicine syndromes of vascular dementia (VaD).
METHODSSixty-three VaD patients were divided into three groups. Those willing to be randomized were randomly assigned to receive either acupuncture (random acupuncture group, 24 cases) or rehabilitation training (guided rehabilitation group, 24 cases) for 6 weeks. Those unwilling to be randomized also received acupuncture for 6 weeks (non-random acupuncture group, 19 cases). Patient syndromes and their severity were evaluated before treatment (baseline), at the end of treatment, and at 4-week follow-up after the completion of treatment using a CM scoring system (scale of differentiation of syndromes of vascular dementia, SDSVD). The SDSVD scores of the random and non-random acupuncture groups, and of all patients who received acupuncture (combined acupuncture group, 43 cases), were compared with those in the guided rehabilitation group.
RESULTSIn the random, non-random, and combined acupuncture groups, SDSVD scores were significantly reduced at the end of treatment and at follow-up than at baseline. In the guided rehabilitation group, SDSVD scores were similar to baseline scores at the end of treatment and at follow-up. However, there were no significant differences in SDSVD scores among the three groups or between the combined acupuncture group and the guided rehabilitation group at any time points. In the non-random and combined acupuncture groups, SDSVD scores were significantly reduced at the end of treatment than at baseline in patients with hyperactivity of Liver (Gan)-yang or phlegm obstruction of the orifices.
CONCLUSIONSAcupuncture reduced the severity of VaD. The improvement was the greatest in patients undergoing their treatment of choice. Treatments in this study were more effective for excess syndromes, such as Liver-yang hyperactivity or phlegm obstruction of the orifices than deficiency syndromes, such as Kidney (Shen)-essence deficiency.
Acupuncture ; Dementia, Vascular ; physiopathology ; therapy ; Humans ; Medicine, Chinese Traditional
8.The construction of lentivirus-mediated RNAi vector containing hTERT.
Peng ZHAO ; Zheng FU ; Yong-ping YOU ; Cun-zu WANG ; Yun-xiang CHENG ; Xiao-ming LU ; Ailin LU ; Ning LIU
Chinese Journal of Medical Genetics 2008;25(1):27-31
OBJECTIVETo construct a recombinant lentivirus RNA interference (RNAi) vector carrying hTERT gene, and to obtain the titer of the lentiviral stock for investigating the expression in the eukaryotic cells and the effect on the hTERT gene silencing in the eukaryotic cells.
METHODSTwo complimentary oligos of small interference RNA (siRNA) with hairpin structures targeting the hTERT gene and a negative control were synthesized, then ligated with pLVTHM vector and sequenced. The recombinant vectors were then transfected with viral packaging mix into T293 cells, viral supernatant was harvested to determine the titer. U87 cells infected by virus were harvested and the expression of hTERT, telomerase activity and apoptosis were detected by reverse transcription-PCR(RT-PCR), TRAP assay and flow cytometry separately.
RESULTSSequencing data showed that the constructed plasmids contained the correct sequences of hTERT siRNA transcript templates. A vector producing cell line T293 was established, and the titer for transfection was obtained. RT-PCR and TRAP flow cytometry analyses demonstrated that hTERT shRNA expression construct could suppress the expression of hTERT and telomerase activity and induce apoptosis.
CONCLUSIONA lentivirus RNAi vector targeting hTERT gene was successfully constructed, which decreased the expression of hTERT and telomerase activity effectively and induced apoptosis. It has set up a research platform for the gene therapy of tumors which take hTERT as the target.
Base Sequence ; Cell Line ; Flow Cytometry ; Gene Knockdown Techniques ; methods ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; Molecular Sequence Data ; Oligodeoxyribonucleotides ; genetics ; metabolism ; Plasmids ; genetics ; metabolism ; RNA Interference ; RNA, Small Interfering ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Telomerase ; biosynthesis ; genetics
9.Effect of the 18kDa translocator protein on U251 cells of human glioma
Hui-Zhong XU ; Wei-Xian YANG ; Cun-Zu WANG ; Qi OUYANG ; Li-Rong DUAN ; Xie-Yun XIONG ; Qing-Hua HE ; Ding-Chao XIANG ; Jie SUN
Chinese Journal of Neuromedicine 2012;11(3):228-234
Objective To study the effect of the 18kDa translocator protein (TSPO) on U251cells of human glioma. Methods U251 cell line was cultured in vitro conventionally.The specific ligand ofTSPO,pk11195,was used in 5 experimental groups respectively with concentrations of 100,50,25,12.5 and 6.25 μmol/L,in comparison with a control group.MTr colorimetry and trypan blue staining were used to detect cell proliferation.Hoechst33342 staining and flow cytometry were applied to detect cell apoptosis. Western blotting and immumofluorescence method were used to detect the expression level of TSPO. DCFH-DA probe and GSH kit were used to respectively detect the level of reactive oxygen species (ROS) and GSH level in cells.Jc-1 staining was applied to detect the mitochondrial membrane potential.Luciferase enzyme was used to detect the quantity of ATP in cells. Results MTT showed the survival of U251 cells was significantly higher in the groups of 50 and 25 μmol/L pk11195than in the control group (P<0.05). Trypan blue staining showed the cell death rate was significantlylower in the group of 50 μmol/L pk11195 than in the control group (P<0.05).The apoptosis rate,TSPO expression,ROS and GSH levels decreased significantly in the groups of 6.25 and 50 μmol/L pk11195,compared with the control group; the apoptosis rate was significantly lower in the group of 50 μmol/Lpk11195 than in the group of 6.25 μmol/L pk11195 (P<0.05).The cell membrane potential and ATP quantity were significantly higher in the groups of 6.25 and 50 μmol/L pk11195 than in the control group,and those in the group of 50 μmol/L pk11195 were significantly higher than in the group of 6.25 μmol/Lpk11195 (P<0.05). Conclusion TSPO may promote apoptosis of U251 cells in human glioma and inhibit proliferation of glioma cells,functioning similarly as a cancer suppressor gene.
10.Study on plague pathogeny in areas along Qinghai-Tibet Railroad in Qinghai from 2001-2006
Zhi-zheng, QI ; Zu-yun, WANG ; Jian, HE ; Rong-jie, WEI ; Hai-hong, ZHAO ; Qing-wen, ZHANG ; Xiao-yan, YANG ; Cun-xiang, LI ; Rui-xia, DAI ; Yong-hai, YANG ; You-quan, XIN ; Hai-tao, ZHAI ; Xing-hai, MAO ; Hong-wen, QI ; Yong, XIAO
Chinese Journal of Endemiology 2008;27(2):204-206
Objective To study the features of Yersinia pestis(Y.pestis)in areas along Qinghai-Tibet Railroad in Qinghai Province.Methods To identify the biologic types and the molecular biological feathers of Y.pestis isolated from areas along Qinghai-Tibet Railroad in Qinghai from 2001-2006.Results All the tested Y.pestis was biologically of classical type and ecologically of Qinghai-Tibet plateau type.The Y.pestis had high virulence.The Y.pestis of 65×106 plasmids was distributed in the Tanggula area,the Y.pestis of 52×106plasmids,in Tianjun and Delingha areas.The Y.pestis srains carried 52 × 106 plasmids.except the two containing 65 X 106 plasmids in Wulan County.The genetic type of Y.pestis in Tanggula was type 5 and that in Zongwulong of Delingha,Saishike,Keke,Tongpu of Wulan was type 8 except 2 strains of Y.pestis isolated from woodchuck and the patients in Dananwan of Tongpu,Wulan County were type 15.Conclusion The Y.pestis in the area along Qinghai-Tibet Railroad in Qinghai belongs to Qinghai-Tibet plateau type with high virulence.