Objective:To evaluate the anti-HIV-1 activity of two new nonnucleoside reverse transcriptase inhibitors (NNRTIs), JB25 and JB26, in combination with 3 approved drugs (AZT, EFV, SQV)in vitro.Methods:The serially diluted 10 concentrations of JB25 and JB26 were combined with 7 serially diluted AZT, EFV and SQV respectively.The combination was added to 384 cell culture plates and then cocultured with HIV-1 ⅢB infected MT-2 cells for 3 days. Finally, the HIV-1 production was determined by measuring the expression of reporter genes of TZM bl cells. The data were analyzed by MacSynergy Ⅱ software.Results:The average capacity of synergism/antagonism of JB25 with AZT, EFV and SQV was 244.45/-5.05(nmol/L)~2%, 119.58/-65.93 (nmol/L)~2% and 145.83/-0.32 (nmol/L)~2% respectively;the average capacity of synergism/antagonism of JB26 with AZT, EFV and SQV was 398.90/0(nmol/L)~2%, 103.62/-0.49(nmol/L)~2% and 138.473/-0.27 (nmol/L)~2% respectively. Conclusion:Two new NNRTIs JB25 and JB26 develop synergism when combined with 3 approved drugs, respectively. MacSynergy Ⅱ software could evaluate the anti-HIV-1 activity of drug combination.

OBJECTIVETo clone, identify and phylogenetically characterize a clade B-Thai HIV isolate representing the most prevalent virus in Henan province.

METHODSPeripheral blood mononuclear cells (PBMCs) from an HIV-1 infected patient in Henan Province were separated, and co-cultivated with phytohemagglutinin-stimulated healthy donor PBMCs. Proviral DNA was extracted from productively infected PBMCs. The full-length HIV-1 genome was amplified by using the LA Tag long template PCR system. Primers were positioned in conserved regions within the HIV-1 long terminal repeats. Purified PCR products were T-A ligated into a pWSK29-T vector(CNHN 24 clone). Three recombinant clones containing virtually full-length HIV-1 genome were identified by PCR. The full-length genome was sequenced by using the primer-walking approach. Nucleotide sequence similarities were calculated by the local-homology algorithm. Phylogenetic trees of gag, pol and env reading frames were constructed using the Phylip software.

RESULTSHIV-1 C3V4 sequences indicate that the epidemic in this area was B-Thai subtype. V3 loop multiple amino acid sequence alignments showed amino acid alterations at nine positions. The 9,010 bp genomic sequence derived from isolate CNHN 24 contained all known structural and regulatory genes of an HIV-1 genome. No major deletions, insertions, or rearrangements were found. The highest homologies of the gag, pol, vpr, and vif reading frames to the corresponding clade B-Thai RL 42 sequences were 95.42%-97.08%. Phylogenetic trees showed the closest relationship of CNHN 24 and RL 42.

CONCLUSIONThe cloning and characterization of a virtually full-length HIV-1 B-Thai subtype in central China was completed in our laboratory. The data should be helpful to future studies on the genetic diversity of HIV-1.

Amino Acid Sequence ; Base Sequence ; Blood Donors ; China ; Cloning, Molecular ; DNA, Viral ; genetics ; Female ; Genome, Viral ; HIV Infections ; virology ; HIV-1 ; classification ; genetics ; Humans ; Leukocytes, Mononuclear ; virology ; Phylogeny ; Reading Frames ; Sequence Analysis, DNA ; Sequence Homology

Objective:To investigate the subtype distribution of HIV-1 strains prevalent in four areas of China,and to study the characteristics of gag gene variation and changes in antigen epitopes under the host immune pressures. Methods:The plasma of HIV-1 infected people from Henan, Guangdong, Sichuan and Beijing in China were collected. Virion RNA was extracted directly from plasma after the virion was condensed. The gag gene was amplified by RT-PCR and nested-PCR.Sequences were subtyped by Genotyping Tool software, and phylogenetic analysis of gag gene were performed using the MEGA 4.1 software.The gene distances intra each subtype were calculated by Distance program. The Ks/Ka ratios were calculated using SNAP program. The variation analysis of CTL antigen epitopes restricted by main HLA-Ⅰ specificities in China was performed.Results:Six subtypes or circulating recombinant forms(CRFs)of HIV-1,including B',CRF07_BC,CRF01_AE,B,CRF08_BC and CRF02_AG,were identified in four areas of China.The gene distances intra each subtype were CRF01_AE>B>CRF08_BC> CRF07_BC>B' listed in order of size, meanwhile the order of Ks/Ka ratios was CRF01_AE>B>CRF08_BC>B'>CRF07_BC. Far more diversity of antigen epitopes in P17 region was observed than that in P24.Epitope mutations intra subtypes were CRF01_AE>B>B'>CRF07_BC listed in order of size. Conclusion:Itseems that CRF01_AE is under the strongest immune pressures,and displays the most diversity of gene and variation of epitopes intra subtypes prevalent in China, followed by subtype B, B' and CRF07_BC. The discrepancy of epitope mutations intra the subtypes is significant.

OBJECTIVEFrequency, type and clinical implications on protease and reverse transcriptase drug resistance mutations were investigated and phylogenetic analysis in antiretroviral drug-naïve AIDS patients was carried out in Henan province.

METHODS45 plasma samples were separated from the anticoagulatory whole blood, from which reverse transcription-polymerase chain reaction technique was used to amplify the partial pol gene. The sequences were analysed for genotypic antiretroviral resistance and phylogenetic relation through landing the websites http://hivdb.stanford.edu and http://hiv-web.lanl.gov, under BioEdit and DNAClub software.

RESULTSPartial pol sequences of 36 samples were successfully amplified. The major mutation rate of resistance to protease was 8.3% (3/36), including types D30A, V32A, G73C and V82A. Minor mutation rate of resistance was 100%, including types of L63PS (36/36), I93L (35/36), V77IL (34/36), A71IVT (10/36) and D60E (2/36). The mutation rate of resistance to reverse transcriptase was 38.9% (14/36). Mutation-scoring and clinical implication clewed drug resistance rates were 5.6% (2/36) and 22.2% (8/36) to protease inhibitors and reverse transcriptase inhibitors respectively, while 1 sample was potentially low-level resistant to all of the protease inhibitors and 3 samples to part of the reverse transcriptase inhibitors. Phylogenetic analysis revealed that the pol gene of 36 samples were highly homologous and having a near relative to B.US.83.RF ACC M17451. 36 samples seemed to have the same infection source while their resistance mutations were not due to drug-resistant virus infection but to the evolving of virus in vivo.

CONCLUSIONMost of the antiretroviral drug-naïve AIDS patients in Henan province were sensitive to the currently available antiviral medicine, but antiviral treatment must be in accordance with the strict procedure and to keep better adherence, to avoid the epidemics caused by drug-resistant virus.

Acquired Immunodeficiency Syndrome ; genetics ; Adult ; Anti-HIV Agents ; pharmacology ; China ; Drug Resistance, Viral ; genetics ; Female ; Genes, pol ; genetics ; Genotype ; HIV Protease ; genetics ; HIV Protease Inhibitors ; pharmacology ; Humans ; Male ; Mutation ; Phylogeny ; RNA-Directed DNA Polymerase ; genetics ; Reverse Transcriptase Inhibitors ; pharmacology

Objective To determine whether morphine having the ability to influence the antiviral effect of lamivudine(3TC)in vitro study.Methods MT2 cells were randomly assigned into morphine+3TC treatment group,morphine+naloxone+3TC treatment group,naloxone+3TC treatment group.Both 3TC and virus control groups were set up.The corresponding MT2 cells were treated with opiates antagonist(naloxone)for 0.5 hours before the 24-hours morphine treatment program was implemented while all of the groups were then infected with equal amounts of cell-free HIV-1 ⅢB strain and 3TC.HIV-1 p24 antigen in culture supernatants collected at days 3,4,5 and 6after infection status was tested and the inhibition of 3TC anti-HIV-1 p24 antigen of various treatment groups calculated.Results Inhibition of 3TC anti-HIV-1 p24 antigen of Morphine+3TC treatment group was the lowest when HIV-1 infected cells at 3rd and 4th day and showed significant difierence (P<0.05)when compared to the 3TC control.However,there was no statistically significant difference among them(P>0.05),when virus was infected the cells at 5th and 6th day.The difference of 3TC anti-HIV-1 p24 antigen inhibition between the morphine+naloxone+3TC treatment group and the naloxone+3TC treatment group was not significant(P>0.05).Similar results were obtained when these two groups were compared to the 3TC control group(P>0.05),respectively.The 3TC anti-HIV-1 p24 antigen inhibition of each treatment group reduced as the time of infection prolonged,showing a significant and time-course effbct.Conclusion The 3TC antiviral effect was reduced by morphine in the early stage of infection,and could be blocked by naloxone.

OBJECTIVETo investigate the factors of the human immunodeficiency virus (HIV) associated with sexual-transmission in central China.

METHODS(1) Cross-sectional study: couples that one was HIV positive were selected in Henan and Hebei province of China. The couples must be 20 - 50 years old with normal function on sexual intercourse. Cordant couples that subsequently infected partners were at risk of infection solely through sexual contact with the HIV-seropositive partner and the discordant couples that the seronegative partners were at risk of infection solely through sexual contact with the HIV-seropositive partner, were selected. Plasma viral load, CD4 cell count were tested. (2) Case-control study was used to compare 7 sexual transmitted cases and 56 nontransmitted controls with respect to the frequency of sexual intercourse, plasma viral load and CD4 cell count.

RESULTS(1) A total of 87 couples that at least one partner was HIV positive were recruited include 56 discordant couples and 7 cordant couples with whom sexual transmission had happened. The rate of sexual transmission was 11.1% among those at the risk of sexual transmission. (2) Of the discordant couples, male positive rate 25%, female positive was 75%. (3) The risk for transmission was higher in those couples with the frequency of unprotected vaginal sexual intercourse (> or = 4 times per month) than the reference group (< 4 times per month) (Fisher's exact test, P = 0.047, OR = 8.0). Median plasma viral load was significantly higher in the antecedent infected partners of cordant couples than the positive partner of discordant couples (378,285.71 vs 136,578.57 copies/ml, t = 3.591, P < 0.01). The odds ratio was 22.0 for plasma viral load > or = 100,000 copies/ml compared with the reference group of < 100 000 copies/ml (Fisher's exact test, P = 0.016). The CD4 cell count and CD4/CD8 of the transmitted group were significantly lower than that of the nontransmitted (t = 2.767, P < 0.05; t = 6.06, P < 0.05).

CONCLUSIONSThe frequencies of heterosexual-transmission in central China were relatively low. The risk of heterosexual transmission was related to the frequency of sexual intercourse. Higher plasma viral load and lower CD4 count was strongly correlated with high risk of heterosexual transmission.

Adult ; Blotting, Western ; CD4 Lymphocyte Count ; China ; Coitus ; Cross-Sectional Studies ; Disease Transmission, Infectious ; Female ; HIV ; immunology ; HIV Infections ; transmission ; Heterosexuality ; Humans ; Male ; Middle Aged ; Risk Factors ; Spouses ; Viral Load

JB25 and JB26 are new HIV-1 nonnucleoside reverse transcriptase inhibitors, and show potent anti-HIV activities. Sequential passage experiments with wild-type virus were performed to select and identify mutations induced by these two compounds in vitro. For the initial passage, compounds were present at approximately 2-fold IC50 in MT-2 cells. When cytopathic effect (CPE) was observed in more than 75% of the cells, the culture supernatants were collected. For the subsequent passages, fresh MT-2 cells were infected with 1 mL supernatants from the previous passage (regardless of the virus titer) and cultured in the presence of the compounds at concentrations that were increased 2-fold compared with that in the previous passage. This procedure was repeated with increasing concentrations for 12 passages. JB25 had amino acid substitution L100I (TTA-->ATA) at passage 6, and then changed into 100 M (ATA-->ATG) at passage 12, which was rare mutation form and had not been reported. At the same time, Y188C (TAT-->TGT) mutation appeared at passage 10. For JB26, there was a L100I (TTA-->ATA) mutation at passage 10. In a word, JB25 and JB26 showed a low genetic barrier to the development of resistance, and the resistance to JB26 developed slower than JB25. The mutations selected by JB25 and JB26 were mainly associated with codons 188 and 100 of HIV-1 reverse transcriptase.
Amino Acid Sequence ; Amino Acid Substitution ; Anti-HIV Agents ; pharmacology ; Cell Line ; Codon ; Drug Resistance, Viral ; HIV Reverse Transcriptase ; antagonists & inhibitors ; genetics ; HIV-1 ; drug effects ; enzymology ; genetics ; Humans ; Mutation ; Reverse Transcriptase Inhibitors ; pharmacology

BACKGROUNDVirus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance. For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations.

METHODS3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay.

RESULTS3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages.

CONCLUSIONSThe NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly.

Cell Line ; Drug Resistance, Viral ; genetics ; HIV-1 ; drug effects ; genetics ; growth & development ; physiology ; Humans ; Lamivudine ; pharmacology ; Mutation ; Nevirapine ; pharmacology ; Reverse Transcriptase Inhibitors ; pharmacology ; Reverse Transcriptase Polymerase Chain Reaction ; Virus Replication ; genetics ; physiology

OBJECTIVETo establish a cohort of human immunodeficiency virus (HIV) discordant couples for follow-up studies and to collect data on frequency of HIV heterosexual transmission and related factors.

METHODSA total of 52 HIV discordant couples were identified by face to face interview and serological testing, in which the HIV negative individuals had no HIV infection behaviors including injecting drug use, blood transfusion or having sexual partners other than his/her own wife/husband. Three times of follows-up studies were carried out in 0.5 year, 1 year and 2.5 years to collect information on their sexual practices and condom use through face to face interview together with 20 ml whole blood collected to test HIV antibody, CD4+ T cell count and viral load.

RESULTS(1) In the period of 2.5 years follow-up, no HIV seroconversion and HIV transmission was found. (2) The frequencies of sexual intercourse between once per month to once per week were 65.4%, 72.9%, 71.7% and 80.0% at the time of cohort setup: 0.5 year, 1 year and 2.5 years of follow-up respectively. The rates of "occasional use" to "never use" condoms were 76.9%, 66.6%, 69.1% and 60.0% at the time of cohort setup as: 0.5 year, 1 year and 2.5 years of follow-up, respectively. No significant difference between different times of follow-up for sexual intercourse or condom use. (3) 85.4%, 66.6% and 60.0% of the HIV positive individuals kept their CD4+ T cell count stabilized or raised during the 0.5 year, 1 year and 2.5 years follow-up period, respectively. However, 66.7% of them showed stable or declined viral load in the period of 2.5 years follow-up. It appeared that stable or raised CD4+ T cell and the stable/declined viral load happened simultaneously.

CONCLUSIONNo transmission was identified in this study. The stabilized CD4+ T cell count and viral load might be account for the reason of no transmission while the biological factors from host and virus related with transmission need to be further studied.

CD4 Lymphocyte Count ; China ; epidemiology ; Cohort Studies ; Coitus ; Condoms ; Contraception Behavior ; Female ; HIV ; physiology ; HIV Infections ; epidemiology ; immunology ; transmission ; virology ; Humans ; Male ; Rural Health ; Spouses ; Viral Load

BACKGROUNDIt is very important for the clinical management to test for minor HIV-1 resistance mutations accurately and sensitively. The conventional genotypic assays of HIV drug resistance detection based on sequencing can only discriminate the mutations which present in more than 20% - 30%. The aim of this study was to evaluate allele-specific real-time PCR (ASPCR) to detect the resistance-related mutations located at positions 103, 184 and 215.

METHODSWe developed the allele-specific PCR assay, using the most common drug resistance mutations in Chinese AIDS patients, K103N, M184V/I, T215F/Y as a model system. The standards were constructed by cloning the wild-type and mutant DNA fragments into the T-vector. We designed specific primers to discriminate mutant templates in the real-time PCR using SYBR green as a fluorescence reporter. And then we evaluated the ASPCR assay and tested 140 clinical samples using this method.

RESULTSThe sensitivities of ASPCR assay were 0.04% for K103N, 0.30% for M184I, 0.40% for M184V, 0.03% for T215F and 0.02% for T215Y. The intra-assay and inter-assay coefficients of variation were less than 0.42. One hundred and forty plasma samples were tested by ASPCR and dynamic resistance curves of ten patients were obtained.

CONCLUSIONSDrug resistance emerged half a year after the start of antiretroviral therapy. The mutation of T215Y emerged 1 to 1.5 years after starting treatment and then increased rapidly. The ASPCR assay we developed was a sensitive, accurate and rapid method to detect the minor HIV-1 variants and it can provide earlier and more drug-resistance information for HIV research and AIDS antiretroviral therapy.

Alleles ; Drug Resistance, Viral ; HIV-1 ; drug effects ; genetics ; Humans ; Mutation ; Real-Time Polymerase Chain Reaction ; methods ; Reproducibility of Results ; Sensitivity and Specificity