title: Development and evaluation of a national reference panel of HIV-1 protease and reverse transcriptase drug-resistance mutations for HIV-1 genotypic resistance assays in China.
abstract: BACKGROUND
  Transmission of antiretroviral drug-resistant strains of HIV-1 has a major impact on the success of HIV treatment regimens in most countries where antiretroviral therapy (ART) is available. It is now recommended that HIV-1 drug resistance be monitored in order to recommend appropriate therapy for infected ART-naïve individuals, or when choosing a new regimen for those patients not responding to ART. Commercial assays for the analysis of HIV-1 genotypic resistance have been approved by the US FDA. In China, several laboratories and research enterprises have been developing related assays, but at present, no systematic standardization or quality control for genotypic resistance assays has been established in China. A national reference panel is needed to evaluate and control the quality of HIV-1 genotype resistance assays in China.
  
  
  METHODS
  A panel of five HIV-1 stocks (G1, G2, G3, G4, and G5) with well-characterized drug resistance was used to evaluate the resistance-mutation inclusivity of HIV-1 clades prevalent in China. Six samples (GS1-GS6) were used to evaluate the limit of detection (LOD) for the viral load levels, and five samples (GSS1-GSS3, GSS5, and GSS6) were used to evaluate the LOD for the percentages of mutant species within the range of detection. The samples were evaluated by five separate laboratories using one or two methods each, generating seven datasets in all.
  
  
  RESULTS
  In samples G1-G5, which were used to evaluate inclusivity of HIV-1 clades, 92.86-100%, 16.67-83.33% and 4.17-8.33% of the most, intermediately, and least common resistance mutations, respectively, were reported by the seven datasets. For the LOD samples, four of the seven datasets reported correct resistance mutations in samples with minimal viral loads of >2 x 10(3) copies/mL, as well as in samples with >40% of mutants and viral loads of about 1 x 10(4) copies/mL; the other three tests did not amplify the target region or identify the mutants.
  
  
  CONCLUSIONS
  The results were quite variable between different tests. The panel of HIV-1 genotypic resistance could be used as a control for resistance testing in China.
authors.affiliation: Department of Cell Biology, National Institute for the Control of Pharmaceutical and Biological Products, Beijing, China.
authors.forename: Sihong
authors.initials: S
authors.lastname: Xu
authors.forename: Jingyun
authors.initials: J
authors.lastname: Li
authors.forename: Zuoyi
authors.initials: Z
authors.lastname: Bao
authors.forename: Hui
authors.initials: H
authors.lastname: Xing
authors.forename: Ping
authors.initials: P
authors.lastname: Zhong
authors.forename: Hanping
authors.initials: H
authors.lastname: Li
authors.forename: Haiwei
authors.initials: H
authors.lastname: Zhou
authors.forename: Xinping
authors.initials: X
authors.lastname: Li
authors.forename: Sharon
authors.initials: S
authors.lastname: Wu
authors.forename: Aijing
authors.initials: A
authors.lastname: Song
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Li
authors.forename: Jianhui
authors.initials: J
authors.lastname: Nie
authors.forename: Youchun
authors.initials: Y
authors.lastname: Wang
mesh_terms: D019380:Anti-HIV Agents / Q000627:therapeutic use; D000911:Antibodies, Monoclonal; D000077552:Basiliximab; D024882:Drug Resistance, Viral / Q000235:genetics*; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy / Q000235:genetics / Q000821:virology; D016333:HIV Protease / Q000235:genetics*; D054303:HIV Reverse Transcriptase / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D057230:Limit of Detection; D011993:Recombinant Fusion Proteins
chemical_list: D019380:Anti-HIV Agents; D000911:Antibodies, Monoclonal; D011993:Recombinant Fusion Proteins; D000077552:Basiliximab; D054303:HIV Reverse Transcriptase; D016333:HIV Protease