BACKGROUNDConstruction of replication-deficient recombinant adenovirus expressing gag-pol and env genes of human immunodeficiency virus (HIV) in mice.

METHODSgag-polDelta and gp140TM genes were cloned into shuttle vector pAdTrack-CMV respectively, and then the plasmids containing gag-polDelta or gp140TM gene were cotransformed with the backbone of adenovirus into E.coli BJ5183. Transfections of the recombinants were performed to obtain recombinant adenoviruses. Its immunogenicity was evaluated by testing antibody levels of mice primed with DNA vaccines and boosted with recombinant adenoviruses.

RESULTSThe replication-deficient recombinant adenovirus could express Gp140TM, Gag P55 and P24 proteins correctly. The mice primed with DNA vaccines and boosted with recombinant adenoviruses elicited high titer of HIV-1-specific antibody compared with that inoculated with DNA vaccines only.

CONCLUSIONReplication-deficient recombinant adenovirus expressing gag-polDelta and gp140TM can elicit high titer HIV-1-specific antibodies.

AIDS Vaccines ; immunology ; Adenoviridae ; genetics ; Animals ; Female ; Fusion Proteins, gag-pol ; biosynthesis ; genetics ; Gene Products, env ; biosynthesis ; genetics ; HIV-1 ; genetics ; immunology ; Mice ; Mice, Inbred BALB C ; Recombination, Genetic ; Transfection ; Vaccines, DNA ; immunology ; env Gene Products, Human Immunodeficiency Virus

Strict regulation of HIV-1 PR function is critical for efficient production of mature viral particles. During viral protein expression and viral assembly, HIV-1 PR located within Gag-Pol precursor must be inactive to prevent premature cytoplasmic processing of the viral Gag and Gag-Pol precursors. Premature activation of HIV-1 precursors leads to major defects in viral assembly and production of viral particles. A cell-level premature activation of HIV-1 precursors assay using bioluminescence resonance energy transfer (BRET) was established. Three thousand compounds were screened to evaluate this assay. The results showed that the assay is sensitive, specific and stable (Z' factor is 0.905).
Anti-HIV Agents ; pharmacology ; Benzoxazines ; pharmacology ; Bioluminescence Resonance Energy Transfer Techniques ; methods ; Fusion Proteins, gag-pol ; genetics ; metabolism ; HEK293 Cells ; HIV Protease ; metabolism ; physiology ; HIV-1 ; enzymology ; High-Throughput Screening Assays ; methods ; Humans ; Plasmids ; genetics ; Protein Precursors ; metabolism ; physiology ; Pyridazines ; pharmacology ; Transfection ; Virion ; growth & development ; Virus Assembly ; gag Gene Products, Human Immunodeficiency Virus ; genetics ; metabolism

To study the CTL antigen epitopes and drug resistance mutations of HIV-1 gag and pol genes through analyzing gag and pol gene sequences. The HIV-1 gag and pol gene fragments were amplified using nested polymerase chain reaction. A total of 23 PCR sequences, 449 cloned gag sequences and 402 cloned pol sequences were obtained. Sequence analyses showed the 23 samples were subtype B or B'. A total of 4 in 8 CTL antigen epitopes appeared 8 mutations in consensus sequence of subtype B and B'. There were no mutations found in the PCR sequences, whereas a few mutations were found in clone sequences (9.80%) in 5 antigen epitopes in p24 region. Eighteen PIs-related mutations and 24 RTIs-related mutations were found in PCR sequences and clone sequences in pol gene region, in which 17 (94.44%) PIs-related mutations and 15 (62.50%) RTIs-related mutations were found only in the clone sequences, respectively. The results showed that the prevalence of HIV-1 drug resistance strains in this study was at a higher level (17.39%), suggesting that some samples were resistant.to existing antiviral drugs.
Antigens, Viral ; immunology ; DNA Mutational Analysis ; Drug Resistance, Viral ; genetics ; Epitopes ; immunology ; HIV-1 ; classification ; drug effects ; genetics ; immunology ; Human Immunodeficiency Virus Proteins ; genetics ; Mutation ; Phylogeny ; T-Lymphocytes, Cytotoxic ; immunology ; gag Gene Products, Human Immunodeficiency Virus ; genetics ; pol Gene Products, Human Immunodeficiency Virus ; genetics

This study aims to compare the influence of different genes to the results of HIV-1 subtype B' phylogenetic analyses. We first split 47 near full-length genome sequences of subtype B' into different regions (gag, pol, vif, vpr, vpu, env, nef), which derived from various risk populations and geographic regions from Thailand, Myanmar and China from published studies. Phylogenetic analyses were performed to each region obtained. The phylogenetic results of different regions were compared to that of the near full-length genome sequences. The pol gene was found to have the lowest diversity and evolutionary rate, and could repeat the phylogenetic results by using near full-length genome sequences. Although the env gene has the highest diversity and evolutionary rate, it could not achieve the similar results. This study compared the influence to the results of HIV-1 subtype B' phylogenetic analyses by using different genes and laid foundation for further molecular survey and analyses of the transmission of subtype B' in China.
Amino Acid Sequence ; China ; epidemiology ; Cluster Analysis ; Genes, Viral ; genetics ; HIV-1 ; classification ; genetics ; Molecular Epidemiology ; Molecular Sequence Data ; Phylogeny ; pol Gene Products, Human Immunodeficiency Virus ; chemistry ; genetics

OBJECTIVETo investigate the distribution and proportion of subtypes of pol gene in HIV-1 epidemic strains in Guangxi Autonomous Region.

METHODS152 HIV-1 patients were enrolled from 11 cities in Guangxi Autonomous Region from 2010 to 2012 by convenient sampling. Inclusion criterias were listed as the fdlowing: HIV-1 infection was confirmed by Western blot, HIV-1 viral load >1 000 copies/ml, > 18 year-old, and without any serious illnesses. 5 ml of peripheral blood samples were obtained from each patient. The viral RNA was isolated from plasma and used for amplification of full-length pol gene by nested RT-PCR. The amplified products were sequenced. After editing and modification, all sequences were characterized for preliminary subtyping by genotyping and confirmed with phylogenetic tree constructed by MEGA 5.03 software. The recombinant identification of 2 unknown recombinant strains was determined by RIP and jpHMM at GOBICS.

RESULTSAmong 152 patients, 137 full-length pol genes were successfully amplified and 127 HIV-1 subtypes were identified. The distribution and proportion of subtypes was summarized as the following 71 cases of CRF01_AE, accounting for 55.9% (71/127), 38 CRF08_BC, 29.9% (38/127), 13 CRF07_BC, 10.2% (13/127), and 3 B (B'), 2.4% (3/127), 2 unknown recombinant strains, 1.6% (2/127). In 11 cites of Guangxi Autonomous Region, subtype CRF01_AE was the dominant strain. Among heterosexual transmitted patients and drug abusers, the proportions of subtype CRF01_AE were 67.4% (58/86) and 34.1% (14/41), respectively. There was a significance different in the distribution of CRF01_AE in different routes of transmission (χ(2)=15.07, P<0.001). In age 21- 35, age 36- 60 and age>60 groups, the proportions of CRF01_AE was 43.6% (17/39), 57.6% (38/66), 77.3% (17/22), and CRF08_BC was 43.6% (17/39), 28.8% (19/66), 9.1% (2/22), respectively, the difference in proportions was significant(χ(2)=8.48, P= 0.014). The patterns of two unknown recombinant strains were found to be CRF01_AE/B (B') and CRF01_AE/C/B(B'), respectively.

CONCLUSIONCRF01_AE was the dominant HIV-1 subtype in Guangxi Autonomous Region from 2010 to 2012, with heterosexual transmission as its main spreading route. The two unknown recombinant strains in Guangxi Autonomous Region were reconstructed by subtype CRF01_AE and CRF_BC.

Blotting, Western ; China ; epidemiology ; Cities ; Drug Users ; Genes, pol ; Genotype ; HIV Infections ; epidemiology ; transmission ; virology ; HIV-1 ; genetics ; Humans ; Phylogeny ; Polymerase Chain Reaction ; RNA, Viral ; blood ; pol Gene Products, Human Immunodeficiency Virus ; genetics

Objective: To understand the epidemiological characteristics of one large HIV molecular transmission cluster in Jiaxing city, Zhejiang province, 2017 in order to select those people under high-risk and providing basis for programs on prevention. Methods: During 2017, newly diagnosed HIV/AIDS cases in this city were recruited. Plasma samples were collected from subjects, followed by RNA extraction, RT-PCR and nest-PCR for pol gene amplification, before being sequenced and aligned. Mega 6.0 software was used to construct phylogenetic tree, and Cytoscape 3.6.0 software was used to identify HIV molecular transmission clusters. Cases within the large transmission clusters were investigated, using a field-epidemiology-questionnaire. Data related to socio-demographics and previous sexual behaviors were collected and EpiData 3.0 and SPSS 20.0 software were used. Results: In the large transmission cluster with subtype identified as CRF07_BC, in Jiaxing, 2017, 26 cases of the total 30 cases were investigated. A total of 80.8% (21/26) could be identified as newly infected within the last two years and 30.8%(8/26) could be identified as newly infected within the last one year, including 22 cases infected locally. Among several infected cases who were at age 45 years or older, they admitted that they had experienced unprotected sexual contacts in local city for long time and having had more than 10 disclosed sexual contacts within the last two years at the local venues. Conclusions: This molecular cluster had been formed and scaled up quickly in recent two years, it has played an important role in promoting and scaling up the HIV transmission. Three cases identificed as high risk played an importantrde role in scaling up this cluster.
Amplified Fragment Length Polymorphism Analysis ; China/epidemiology* ; Genes, pol ; Genotype ; HIV Infections/transmission* ; HIV-1/isolation & purification* ; Humans ; Molecular Epidemiology ; Phylogeny ; Polymerase Chain Reaction ; RNA, Viral/blood* ; Sexual Behavior ; pol Gene Products, Human Immunodeficiency Virus

OBJECTIVESTo construct and screen a primarily phage display library of HCV C and E1 genes evolved with an artificial pattern.

METHODSTwo genes of about 1 kb with different genotypes were evolved by DNA shuffling. The re-assembled HCV C and E1 genes were cloned into a phage vector. After being rescued with helper phage M13KO7, a phage display library was constructed. Then the library was screened with anti-C and E1 McAb. Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) was carried out on twenty individual phage clones selected randomly to detect their binding and reactive activity with high-titer HCV-positive sera. Normal sera were used as controls.

RESULTSThe phage display library of HCV C and E1 genes which evolved with an artificial pattern was constructed. Their capacity amounted to 1.64 x 10(6), and 86 percent of the clones contained C and E1 genes. After four rounds of panning, the phage library was specifically enriched. Twelve positive clones were successfully screened.

CONCLUSIONThe capacity and diversity of the constructed library are enough for screening. The results demonstrate the superiority of the specific binding and reactive activity and affinity of the 12 phage clones from the HCV positive sera.

DNA, Viral ; genetics ; Gene Library ; Hepacivirus ; genetics ; Peptide Library ; Viral Core Proteins ; genetics ; Viral Envelope Proteins ; genetics

OBJECTIVE: To evaluate the clinical significance of serum hepatitis C virus (HCV) core antigen detected by enzyme linked immunosorbent assay (ELISA). METHODS: The serum HCV core antigen, which was taken from 149 patients with chronic hepatitis C, 20 patients of chronic hepatitis B and 20 health volunteers, was detected by ELISA. Meanwhile, the serum HCV RNA was detected by RT-PCR, and anti-HCV was detected by ELISA. RESULTS: The qualitative HCV core antigen in the serum, which was take from 20 patients of chronic hepatitis B and 20 health volunteers, was negative.The positive percentage of HCV core antigen was 49.66% in the 149 sera of patients with chronic hepatitis C. The coincidence of detective results of HCV RNA and HCV core antigen was 54.36%, without significant difference (P>0.05). The positive percentage of HCV RNA and HCV core antigen in the 149 anti-HCV antibody positive sera samples were 55.03% (82/149) and 49.66% (74/149), respectively, and there was no significant difference (P>0.05). CONCLUSION The qualitative HCV core antigen detected by ELISA has a high specificity. The positive percentage of HCV core antigen in the serum of patients with chronic hepatitis C is 49.66%. HCV core antigen is related to HCV RNA. HCV core antigen may be a useful serum marker which could show HCV viraemia like HCV RNA.
Hepatitis C Antigens ; blood ; Hepatitis C, Chronic ; blood ; Humans ; RNA, Viral ; blood ; Viral Core Proteins ; blood

OBJECTIVETo investigate the biological role of auto-induced expression of hepatitis C virus (HCV) core protein (protein C) using a recombinant protein in an in vitro cell-based system.

METHODSThe PCR-amplified full-length HCV protein C gene (573 bp) was inserted into the pET28a prokaryotic expression vector. The recombinant plasmid was transformed into BL21(DE3)pLysS E. coli to achieve high-concentration expression of the recombinant C protein by auto-induction. The recombinant protein C was purified by Ni-NTA affinity chromatography, and tested in a protein binding assay for its ability to bind the HCV NS3 protein.

RESULTSThe transformed E. coli produced a large amount of recombinant protein C, as detected in the sonicated supernatant of the bacteria culture. The antigenic reactivity of the recombinant protein C was confirmed by western blotting. However, the recombinant protein C could not be purified by Ni-NTA affinity chromatography, but co-precipitated with the HCV NS3 protein.

CONCLUSIONSoluble recombinant protein C was successfully expressed by auto-induction, and shown to interact with the HCV NS3 protein, which provides a novel insight into the putative biological activity of this factor in HCV-related molecular processes. Future studies of this recombinant HCV protein C's crystal structure and antigenicity may provide further clues to its biological function(s) and potential for clinical applications.

Escherichia coli ; metabolism ; Genetic Vectors ; Hepacivirus ; Recombinant Proteins ; genetics ; metabolism ; Viral Core Proteins ; biosynthesis ; genetics ; metabolism ; Viral Nonstructural Proteins ; metabolism

OBJECTIVETo investigate the effects of the hepatitis B virus (HBV) P22e protein on the apoptosis of human hepatocellular carcinoma HepG2 cells.

METHODSHepG2 cells were transfected with recombinant plasmid pEGFP-HBVP22e and exposed to Act-D and tumor necrosis factor alpha (TNFalpha) treatment to induce cell apoptosis. Flow cytometry was performed to determine the proportion of cells containing sub-G1 DNA to represent the number of apoptotic cells. Laser scanning confocal microscopy was used to observe the nuclear alterations in the apoptotic cells.

RESULTSHepG2EGFP-C2HBVP22e cell strain showed a much delayed apoptosis as well as obviously lowered apoptotic rate in comparison with the HepG2 strain (P<0.01).

CONCLUSIONThe introduction and expression of extraneous gene HBVP22e significantly inhibits the apoptosis of HepG2 cells.

Apoptosis ; Carcinoma, Hepatocellular ; metabolism ; Hep G2 Cells ; Hepatitis B Core Antigens ; metabolism ; Humans ; Transfection ; Viral Core Proteins ; metabolism