Nie J.,National Institutes for Food and Drug Control NIFDC |
Nie J.,Jilin University |
Wang W.,National Institutes for Food and Drug Control NIFDC |
Wen Z.,National Institutes for Food and Drug Control NIFDC |
And 11 more authors.
Journal of Virological Methods | Year: 2012
Among the neutralizing antibody evaluation assays, the single-cycle pseudovirus infection assay is high-throughput and can provide rapid, sensitive and reproducible measurements after a single cycle of infection. Cell counts, pseudovirus inoculation levels, amount of diethylaminoethyl-dextran (DEAE-dextran), and the nonspecific effects of serum and plasma were tested to identify the optimal conditions for a neutralizing antibody assay based on pseudoviruses. Optimal conditions for cell counts, pseudovirus inoculation, and amount of DEAE-dextran were 1×104cells/well, 200TCID50/well, and 15μg/ml, respectively. Compared with serum samples, high-concentration anticoagulants reduced the relative light unit (RLU) value. The RLU value increased sharply initially but then decreased slowly with dilution of the plasma sample. Test kits containing 10 HIV-1 CRF07/08_BC pseudovirus strains and 10 plasma samples from individuals infected with HIV-1 CRF07/08_BC were assembled into two packages and distributed to nine laboratories with a standard operating procedure included. For the 10 laboratories that evaluated the test, 17 of 44 (37%) laboratory pairs were considered equivalent. A statistical qualification rule was developed based on the testing results from 5 experienced laboratories, where a laboratory qualified if at least 83% of values lied within the acceptable range. © 2012 Elsevier B.V.
He X.,Centers for Disease Control and Prevention |
Xing H.,Centers for Disease Control and Prevention |
Ruan Y.,Centers for Disease Control and Prevention |
Hong K.,Centers for Disease Control and Prevention |
And 56 more authors.
PLoS ONE | Year: 2012
Background: China is experiencing a dynamic HIV/AIDS epidemic. While serology based surveillance systems have reported the spread of HIV/AIDS, detailed tracking of its transmission in populations and regions is not possible without mapping it at the molecular level. We therefore conducted a nationwide molecular epidemiology survey across the country. Methods: HIV-1 genotypes were determined from 1,408 HIV-positive persons newly diagnosed in 2006. The prevalence of each genotype was estimated by weighting the genotype's prevalence from each province- and risk-specific subpopulation with the number of reported cases in the corresponding subgroups in that year. Results: CRF07_BC (35.5%), CRF01_AE (27.6%), CRF08_BC (20.1%), and subtype B' (9.6%) were the four main HIV-1 strains in China. CRF07_BC and CRF08_BC were the primary drivers of infection among injecting drug users in northeastern and southeastern China, respectively, and subtype B' remained dominant among former plasma donors in central China. In contrast, all four strains occurred in significant proportions among heterosexuals nationwide, pointing to an expansion of the HIV-1 epidemic from high-risk populations into the general population. CRF01_AE also replaced subtype B as the principal driver of infection among men-who-have-sex-with-men. Conclusions: Our study provides the first comprehensive baseline data on the diversity and characteristics of HIV/AIDS epidemic in China, reflecting unique region- and risk group-specific transmission dynamics. The results provide information critical for designing effective prevention measures against HIV transmission. © 2012 He et al.
Shuck-Lee D.,U.S. Army |
Chang H.,Shanghai CDC |
Sloan E.A.,University of Virginia |
Hammarskjold M.-L.,University of Virginia |
Rekosh D.,University of Virginia
Journal of Virology | Year: 2011
Previously we described the identification of two compounds (3-amino-5-ethyl-4,6-dimethylthieno[2,3-b] pyridine-2-carboxamide  and 4-amino-6-methoxy-2-(trifluoromethyl)-3-quinolinecarbonitrile ) that interfered with HIV replication through the inhibition of Rev function. We now describe resistant viral variants that arose after drug selection, using virus derived from two different HIV proviral clones, NL4-3 and R7/3. With HIV NL4-3, each compound selected a different single point mutation in the Rev response element (RRE) at the bottom of stem-loop IIC. Either mutation led to the lengthening of the stem-loop IIC stem by an additional base pair, creating an RRE that was more responsive to lower concentrations of Rev than the wild type. Surprisingly, wild-type HIV R7/3 was also found to be inhibited when tested with these compounds, in spite of the fact this virus already has an RNA stem-loop IIC similar to the one in the resistant NL4-3 variant. When drug resistance was selected in HIV R7/3, a virus arose with two nucleotide changes that mapped to the envelope region outside the RRE. One of these nucleotide changes was synonymous with respect to env, and one was not. The combination of both nucleotide changes appeared to be necessary for the resistance phenotype as the individual point mutations by themselves did not convey resistance. Thus, although drug-resistant variants can be generated with both viral strains, the underlying mechanism is clearly different. These results highlight that minor nucleotide changes in HIV RNA, outside the primary Rev binding site, can significantly alter the efficiency of the Rev/RRE pathway. Copyright © 2011, American Society for Microbiology. All Rights Reserved.
Dong Z.,Anhui Medical University |
Xu J.,National Center for Control and Prevention |
Zhang H.,Anhui Medical University |
Dou Z.,National Center for Control and Prevention |
And 22 more authors.
PLoS ONE | Year: 2014
Objectives: To assess HIV incidence and its associated risk factors among young men who have sex with men (YMSM) in urban areas, China. Design: The study used a prospective cohort study design and standard diagnostic tests. Methods: A twelve-month prospective cohort study was conducted among YMSM (18-25 years old) in 8 large cities in China. The participants were recruited via snowball sampling. A total of 1102 HIV-negative YMSM completed baseline assessment, 878 YMSM participants completed 6-month follow-up, and 902 completed 12-month follow-up. HIV was screened by an enzyme-linked immunosorbent assay and confirmed with Western Blot. Syphilis was screened via rapid plasma reagent and confirmed by treponema pallidum particle agglutination assay. Results: 78 HIV seroconversions were identified within 1168.4 person-year observations yielding an incidence rate of 6.7 per 100 person-years. HIV seroconversion was associated with non-student status (RR = 2.61, 90% CI = 1.3-5.26), low HIV transmission knowledge (RR = 8.87, 90% CI = 2.16-36.43), and syphilis infection (RR = 5.04, 90% CI = 2.57-9.90). Conclusions: Incidence of HIV among YMSM is high in urban areas of China. Interventions measures are required to contain the HIV epidemic within this population. © 2014 Dong et al.