title: Comparison between the automated Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test version 2.0 assay and its version 1 and Nuclisens HIV-1 EasyQ version 2.0 assays when measuring diverse HIV-1 genotypes in China.
abstract: BACKGROUND
  Several commercially available HIV-1 viral load assays based on real-time detection technology and automated platforms are available. It is not clear how the diversity of HIV-1 genotypes impacts the ability to consistently detect HIV-1 viral loads.
  
  
  OBJECTIVE
  To examine whether the diversity of HIV-1 genotypes impacts the ability of the Cobas AmpliPrep/Cobas TaqMan HIV-1 test version 2.0 (CAP/CTM v2.0), its version 1.0 (CAP/CTM v1.0) and the NucliSens EasyQ HIV-1 version 2.0 (EasyQ v2.0) assays to consistently determine the viral loads.
  
  
  METHODS
  The three assays were used to measure the viral load in 178 plasma samples with diverse genotypes from treatment-naive patients.
  
  
  RESULTS
  CAP/CTM v2.0 showed significant correlation and high agreement with CAP/CTM v1.0 and EasyQ v2.0. CAP/CTM v2.0 showed excellent detection of clade B samples compared with CAP/CTM v1.0 and EasyQ v2.0. However, significant differences were observed when using CAP/CTM v2.0 to test clade BC and AE samples. The HIV-1 load measured by CAP/CTM v2.0 differed by >0.5logIU/ml in 59.52% and 72.62% of clade BC samples, and in 57.14% and 85.71% of clade AE samples, compared with CAP/CTM v1.0 and EasyQ v2.0, respectively. CAP/CTM v2.0 was more precise (13.18%) than EasyQ v2.0 (29.21%), and both assays showed good linearity (R≥0.9926).
  
  
  CONCLUSIONS
  The three assays may not deliver consistent results for samples belonging to clades BC and AE. It is strongly suggested that the version of the HIV-1 viral load assay used initially is also used at follow-up.
authors: Department of Cell Biology, National Institutes of Food and Drug Control, No. 2 Tiantanxili, Beijing, PR China.
authors: Sihong
authors: S
authors: Xu
authors: Aijing
authors: A
authors: Song
authors: Jianhui
authors: J
authors: Nie
authors: Xiuhua
authors: X
authors: Li
authors: Shufang
authors: S
authors: Meng
authors: Chuntao
authors: C
authors: Zhang
authors: Youchun
authors: Y
authors: Wang
mesh_terms: D002681:China / Q000453:epidemiology; D019411:Clinical Laboratory Techniques / Q000379:methods; D014644:Genetic Variation; D005838:Genotype; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D015497:HIV-1 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D012367:RNA, Viral / Q000032:analysis / Q000235:genetics*; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019562:Viral Load; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000235:genetics
chemical_list: D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic; D054301:gag Gene Products, Human Immunodeficiency Virus