Objective To investigate the subtype distribution and sequence characteristics of HIV-1 strains prevalent among sexual infectors in Beijing. Methods We collected the blood samples from 100HIV sexual infectors in Beijing during 2008 and separated plasma specimens. RNA was extracted from the plasma and the gag gene was amplified by RT-PCR and nest-PCR. The PCR products were sequenced directly and phylogenetic analyses of gag gene was performed using the MEGA4 software. Results Among 100 HIV-1 plasma samples,84 gag gene fragments were amplified and analyzed. Eight HIV subtypes including B(22 strains), B'(8 strains),C( 1 strain) ,CRF01_AE (38 strains) ,CRF02_AG (2 strains) ,CRF07_BC(9 strains) ,CRF08_BC(3 strains) and C/CRF01_AE recombinant like strain( 1 strain) were identified circulating in Beijing. Conclusion CRF01 _AE and subtype B were predominant in Beijing account for 45.2% and 26.2% and the surveillance of HIV gene variation should be paid more attention.

BACKGROUNDTo characterize the intertype epitopes on human adenovirus (HAdV) hexon.

METHODSBased on computerized analysis on adenoviruses sequence of genomic alignment, antigenicity prediction and 3-D structure characteristics of hexon subunit, several peptides of hexon of adenoviruses were chosen to be synthesized or recombinant proteins of the hexon were expressed in E. coli by use of PGEX-5X. To identify the existence of intertype epitopes, the antisera raised with synthetic peptides or purified recombinant proteins were analyzed with Western blot and immunofluorescent assay.

RESULTSThe results of Western blot indicated that both peptide and recombinant antibodies showed specific reactivities with hexons of HADv-3, 4, 7 individually. Meanwhile, typical stain of immunofluorescence was found on HeLa cells infected with these HAdV by incubation with peptide as well as recombinant antibodies. Also, antibodies raised against peptide recognized the recombinant hexon protein in which a corresponding region of peptides was covered.

CONCLUSIONSMost of the predicted intertype epitopes of HAdV hexon wer e exclusively found in synthetic peptides and recombinant proteins. These intertype epitopes showed to be continuous and sequential which could be employed for development of antibodies of diagnostic use.

Adenoviruses, Human ; immunology ; Amino Acid Sequence ; Animals ; Capsid ; chemistry ; immunology ; Capsid Proteins ; immunology ; Epitopes ; immunology ; HeLa Cells ; Humans ; Mice ; Peptide Fragments ; immunology

Objective: To explore the intra-host genetic evolution of HIV-1 pol gene via follow-up for treatment-naïve HIV infections, and estimate the infection time with Bayesian coalescent theory, so as to support the evaluation of HIV epidemic. Methods: Five cases were recruited and followed up. The pol gene fragments were amplified for the characteristics of transmitted drug resistance ( TDR ) by RT-PCR. Bayesian coalescent theory was utilized to construct maximum clade credibility ( MCC ) tree for genetic evolution and calculate the time to the most recent common ancestor ( tMRCA ). Results: The five cases were all male, and aged from 27 to 50 years old.Five to nine sampling times were obtained from each case, and the pol gene sequences from each case formed a unique subcluster (posterior probability: 100% ), with different evolution characteristics, in the MCC tree. The three cases in primary HIV-1 infection were estimated to be infected one to five months before the first positive reaction of HIV screening, whereas the two HIV-1 diagnosed cases at first screening were extrapolated to get infected fourteen months and seven months before diagnosis, respectively. One case with acute HIV-1 infection carried TDR mutation ( M46I ) , expressing fast disease progress and quasispecies variation. Conclusions The general infection time can be estimated by analyzing the characteristics of intra-host genetic evolution of HIV-1 pol gene with Bayesian coalescent theory, and this method can help to estimate the HIV epidemic.

Objective:To elucidate the quasispecies variation of 3′ half-length genome in HIV-1 CRF103_01B-infected patients in Beijing using single genome amplification (SGA).Methods:This study enrolled six CRF103_01B-infected patients who were diagnosed during a drug resistance monitoring for newly diagnosed cases or newly treated cases with antiviral therapy in Beijing from 2017 to 2020. RNA was extracted from their plasma samples, and 3′ end of cDNA was diluted by serial dilution method after reverse transcription. Nested PCR was used to amplify the 3′ half-length genome sequences of HIV-1 quasispecies. MEGA 11 was used to construct Neighbor-Joining (NJ) tree and calculate the intrahost genetic distance. Genetic variation in HIV-1 quasispecies was visualized by online Highlighter tool. BootScan analysis was performed using Simplot 3.5 software to analyze inter-quasispecies recombination. Virus tropism was predicted by online Geno2pheno tool.Results:Among the six CRF103_01B-infected patients, five were men who have sex with men. A total of 144 3′ half-length genome SGA sequences (19-36 sequences/case) were obtained. The NJ tree based on the 3′ half-length genome of HIV-1 quasispecies revealed different degrees of genetic diversity. The HIV-1 quasispecies in BL4748-00 case of acute infection has the least variation with the intrahost distance of 0.002±0.000, showing genetic homogeneity. The quasispecies sequences from BL4981-00, BL3150-00 and BL3558-00 cases formed at least three subclusters, respectively, with different evolutionary directions, and their intrahost distance ranked from 0.031±0.004 to 0.016±0.002 (BL3150-00>BL3558-00>BL4981-00). The quasispecies sequences from the couple BL3022-00 (female) and BL3023-00 clustered into a large monophyletic cluster (bootstrap value=100%), and the intrahost distance of the latter (0.025±0.003) was higher than that of the former (0.019±0.002). Inter-quasispecies recombination was observed in BL3558-00 case. The quasispecies from the six patients were CCR5-tropic viruses.Conclusions:The diversity of quasispecies variation in CRF103_01B-infected patients is related to disease progress. Genetic homogeneity is observed in acute HIV infection, while multiple evolutionary directions are detected in chronic infection. Co-infection or superinfection cases are not found, but there are recombination events among quasispecies in some cases.

OBJECTIVETo analyze the proportion and associated factors of taking subsequent confirmation test among men who have sex with men (MSM) after being tested positive in oral fluid HIV antibody test.

METHODSBy using successive sampling, 1 003 MSM, who were tested positive in oral fluid HIV antibody test in China-Bill & Melinda Gates Foundation AIDS prevention Program (Extension program) in Beijing during May 1 to December 31, 2013, were recruited. The inclusion criteria included: the objects were men who reported having sex with men; the objects aged more than 18 years old; the objects were tested positive in oral fluid HIV antibody test; the objects had not been reported as HIV positives in China Information System for Disease Control and Prevention previously. According to the program strategy, MSM grassroots organizations transferred the respondents to seek subsequent confirmation tests in specific Center for Disease Control and Prevention (CDCs) or hospitals. The subsequent confirmation tests included: fingertip blood HIV antibody rapid test, venous blood Enzyme Linked Immunosorbent Assay (ELISA) HIV antibody test and venous blood Western Blot (WB) HIV antibody test. Chi-square test was adopted to compare the proportion of taking subsequent confirmation tests in different groups. Nonconditional multivaritae binarylogistic regression analysis was taken to identify the associated factors with whether taking subsequent confirmation tests and to calculate the OR (95% CI) values.

RESULTSThe 1 003 respondents were (30.9 ± 9.1) years old. Among all objects, 87.8% (881/1 003) of them took fingertip blood HIV antibody rapid tests and the positive rate was 85.4% (752/881). 98.0% (737/752) of those who were identified as positive in fingertip blood HIV rapid tests took ELISA and WB tests, and the positive rate was 94.4% (696/737). Comparing with those who were expected to seek subsequent confirmation tests in CDCs, the OR (95% CI) value of those who were expected to seek tests in hospitals was 5.10 (1.69-15.36). The OR (95% CI) values of those who used condom sometimes and those who never used condom in anal sex were 5.81 (2.14-15.77) and 3.45 (2.00-5.97) respectively, in comparison with those who reported not having anal sex or using condom consistently in anal sex during the past 6 months. Comparing with the respondents recruited from the internet, the OR (95% CI) values of those recruited in bathrooms, parks/toilets and bars were 0.17 (0.05-0.53), 0.10 (0.04-0.29) and 0.22 (0.06-0.79) respectively. The likelihood of taking subsequent confirmation test decreased with the increase of number of male sexual partners in the past 3 months, and the OR (95% CI) value was 0.92 (0.86-0.99).

CONCLUSIONThe potential HIV positive MSM in the bathroom, park/toilet and bars are less likely to take subsequent confirmation test. Those who do not use condom consistently during anal sex are more likely to seek subsequent confirmation test. Medical organization conducting subsequent confirmation tests is more likely to increase the confirmation test rate of potential HIV positive MSM. The number of male sexual partners has negative correlation with whether to accept the subsequent confirmation test.

Beijing ; Condoms ; HIV Antibodies ; analysis ; HIV Seropositivity ; diagnosis ; Homosexuality, Male ; Humans ; Male ; Mass Screening ; Patient Acceptance of Health Care ; Risk-Taking ; Sexual Behavior ; Sexual Partners ; Surveys and Questionnaires

Objective:To compare the performance of rapid tests for HIV-1 antibody detection in serum and urine specimens of men who have sex with men (MSM) for investigating suitable technology in the prevention and control of AIDS in Beijing.Methods:A total of 874 cases of MSM were recruited in the AIDS clinic of Beijing Center for Disease Prevention and Control. HIV-1/2 antibody rapid test kit (Kit A, Alere Determine), urine HIV-1 antibody rapid test kit (Kit B, Wantai Biological Pharmacy) and HIV-1/2 antibody Western blot kit (Kit C, IMT) were used for antibody detection. The sensitivity, specificity and consistency of the three rapid test kits for HIV-1 antibody detection in serum and urine specimens were analyzed.Results:Among the 874 cases of MSM, 447 were positive for HIV-1 antibody (51.14%) and 427 were negative. One false negative result occurred by using Kit A and 23 by using Kit B. Taking Kit C as reference, the sensitivity of Kit A and Kit B was 99.78% and 94.85%, respectively; the specificity of both was 100%; the overall consistency was 99.89% ( Kappa=0.998) and 97.37% ( Kappa=0.947), respectively. Conclusions:Although the sensitivity of urine rapid test kit was not as sensitive as serum rapid test kit, it was more suitable for self-test due to its convenience in sampling, high safety and high accessibility. It was suggested that urine rapid test kit should be popularized in MSM population for HIV-1 antibody screening.

Objective:To explore the characteristics of HIV-1 genotypic drug resistance for protease-reverse transcriptase (PR-RT) and integrase (IN) among antiretroviral therapy (ART)-naive individuals in Beijing, and provide evidence for clinical diagnosis and treatment.Methods:Newly diagnosed individuals or cases initiating ART were recruited in Beijing covering 2019 to 2020, then pol gene fragments and integrase gene were synchronously amplified and sequenced. Phylogenetic analyses were performed to determine subtypes, and the pol gene and integrase gene sequences were submitted to Stanford University HIV drug resistance database for the interpretation of mutations and drug resistance. Results:Among 168 ART-naive individuals, 93.6% were infected via men who have sex with men (MSM). The top two subtypes were CRF01_AE (41.0%) and CRF07_BC (30.3%), and unique recombinant forms accounted for 16.1% infections. Six individuals carried surveillance drug resistance mutations in PR-RT, with a prevalence of transmitted drug resistance (TDR) at 3.7%. And one case carried nucleoside reverse transcriptase inhibitor mutation of K65R, accompanied with major integrase mutation of T66I (0.6%), conveying resistance to elvitegravir and raltegravir at high and low levels, respectively.Conclusions:The prevalence of transmitted drug resistance was considerably low among ART-naive individuals in Beijing, and the surveillance of genotypic drug resistance should be strengthened, including integrase drug resistance.

Objective:To establish a nested PCR method to detect the 2019 novel coronavirus (2019-nCoV), as a supplement to the real-time fluorescent PCR method, and discuss the preliminary application value of this method in clinical diagnosis.Methods:According to the conservative sequences of the 2019-nCoV gene, the nested PCR primers including N gene and S gene, were designed on line. By optimizing the nested PCR reaction systems, the qualitative detection was established by testing N gene and sequencing its PCR product while the preliminary type identification was established by testing S gene and sequencing its PCR product. The sensitivity was evaluated by the gradient dilution of 2019-nCoV positive samples’ nucleic acid and the specificity was evaluated by detecting the human coronavirus OC43, 229E, HKU1, NL63, influenza virus positive samples. The established method was applied to 15 samples with Ct >33 and 15 samples with Ct <33 screened by real-time fluorescent PCR, and the positive amplification result were sequenced and analyzed to verify the result. Results:The established nested PCR method could amplify specific bands of 355 bp N gene fragment and 449 bp S gene fragment. No amplifications occurred in other human coronaviruses samples including 229E、OC43、HKU1、NL63 or in influenza virus samples including H3N2, H1N1(pdm) and B. The minimum detection limit of the N gene fragment could reach Ct value about 37.21. Among the 30 COVID-19 positive samples, the N gene positive coincidence rate detected by nested PCR was 100% (30/30); the S gene positive coincidence rate reached 60% (18/30). 28 samples’ sequences of N gene fragment were completely consistent with 2019-nCoV by BLAST, and the characteristic result of site mutations of 12 samples’ S gene was obtained. Conclusions:A nested PCR method for the specific detection of 2019-nCoV was established, and some characteristic mutations on S gene could be analyzed by sequencing the PCR amplified products. It could be used as a supplement to the real-time fluorescent PCR method.

Background::Single-tablet regimen (STR) provides a convenient once-daily regimen for the prevention of human immunodeficiency virus (HIV) infection. Here, we investigated the safety and tolerability of coformulated bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) as a three-drug, STR for post-exposure prophylaxis (PEP) in Chinese individuals.Methods::This was a prospective, open-label, single-arm trial conducted in a sexually transmitted diseases and acquired immunodeficiency syndrome clinic of a tertiary hospital in Beijing, China. Adults requiring PEP were prescribed BIC/FTC/TAF one pill once a day for 28 days. Clinical and laboratory data were collected and analyzed at baseline, weeks 2, 4, 8, 12, and 24.Results::Of 112 participants enrolled in the study, 109 (97.3%) were male and the mean age was 30 ± 8 years. PEP completion was 96.4% (95% confidence interval: 91.1-99.0%). Two participants stopped PEP after 2 days because the source partner was identified as HIV uninfected. One participant was excluded due to hepatitis B virus infection according to the exclusion criteria. One discontinued due to the participant’s decision. No participant acquired HIV through week 24. Adherence was 98.9% (standard deviation [SD]: 3.3%) by self-reporting and 98.5% (SD: 3.5%) by pill count. Only five participants experienced mild clinical adverse events attributed to the study drug (including headache, diarrhea, and nausea) and four participants had elevated serum creatinine (grade 1).Conclusions::A once daily, STR of BIC/FTC/TAF used as PEP was safe and well-tolerated with a high rate of completion and adherence in Chinese. BIC/FTC/TAF may be a good option for PEP.Trial Registration::ChiCTR.org.cn, ChiCTR2100048080

Objective:To analyze the characteristics of viral isolation and unique recombinant from untreated HIV-1 patients infected through sexual transmission and injection drug use, so as to provide evidence for understanding the biological characteristics and precise prevention and control of HIV-1 infection in different transmission routes.Methods:In view of the different HIV-1 transmission risks, newly diagnosed untreated HIV-1 patients from Beijing, Guangxi and Sichuan were carefully selected. Venous blood was collected to detect the viral load and CD4 + T cell count, and peripheral blood lymphocytes were isolated for virus isolation. Viral RNAs were extracted from the virus supernatant, and the near full-length genome sequences were obtained using in-house method, then the recombination patterns were determined. Results:Among the 65 HIV-1 infection, 32(49.2%), 20(30.8%) and 13(20.0%) were infected via men who have sex with men (MSM), heterosexual and injection drug use (IDU), respectively; genotypes mainly included 26(40.0%) CRF07_ BC, 23(35.4%) CRF01_ AE, and 9(13.8%) unique recombinant types (URFs). A total of 46 HIV-1 clinical strains were isolated. The positive rate of HIV-1 isolation was significantly negatively correlated with CD4 + T cells ( X2=4.22, P=0.04), but positively correlated with viral load ( X2=22.4, P<0.001); the multi-variate generalized estimating equations(GEE) model analysis of HIV-1 P24 antigen content showed similar result. In addition, GEE model showed a positive correlation between viral P24 antigen content and virus-producing culture time (52.14, 95% CI: 9.42~94.87, P=0.017). Viral growth curve analysis showed that the level of viral P24 antigen in MSM Group was significantly higher than that in heterosexual group and IDU group (adjusted P values were p<0.01 and P<0.05, respectively), on the 14th day after culture. The proportion of URFs in MSM Group was higher than that in heterosexual group, and the recombinant breakpoints in MSM Group were more than that in heterosexual group. Conclusions:MSM population was more sensitive to HIV-1 virus isolation; there was unique diversity of recombinant forms of HIV-1 among those with sexually transmitted infections, especially in the MSM population.