title: Assessment of a standardized reverse-transcriptase PCR assay for quantifying HIV-1 RNA in plasma and serum.
abstract: The analytical variability of the new commercially available Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) assay, Amplicor HIV-1 Monitor, has been assessed to establish criteria for assessing the significance of HIV-1 RNA level measurements. Estimations of the standard deviations (SD) of log-copies in inter-assay (mean 0.09 log) and in inter-laboratory (mean 0.14 log) reproducibility experiments demonstrated that the assay can discriminate with 95% confidence between 3-fold (inter-assay) and 5-fold differences (inter-laboratory). The inter-lot reproducibility (mean 0.10 log) was similar to the inter-assay reproducibility. The HIV-1 RNA concentrations measured in plasma collected in potassium EDTA anticoagulant were slightly higher than those measured in plasma collected in sodium citrate. The HIV-1 RNA concentrations measured in sera were about 50% of the HIV-1 RNA concentrations measured in paired plasma samples. However, there was a strong correlation between these two measurements (P < 0.0001). The assay was used to measure viral RNA in the plasma of 50 HIV-1 positive individuals at different stages of infection. All the individuals had detectable HIV-1 RNA (300-957000 copies/ml). There was no correlation between HIV-1 RNA and Immune Complex Dissociated (ICD) p24 antigen, but HIV-1 RNA was correlated with CD4+ cell counts (P < 0.0001) and the clinical stage (P = 0.0042), with higher HIV-1 RNA concentrations in patients with a more advanced stage of the disease. The significant association of HIV-1 RNA with major markers of HIV infection and the reliability of this sensitive, easy-to-use RT-PCR assay indicate its suitability for use in clinical trials and suggest that this assay is appropriate for routine clinical applications.
authors.affiliation: Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, France.
authors.forename: J
authors.initials: J
authors.lastname: Izopet
authors.forename: C
authors.initials: C
authors.lastname: Poggi
authors.forename: E
authors.initials: E
authors.lastname: Dussaix
authors.forename: J M
authors.initials: JM
authors.lastname: Mansuy
authors.forename: L
authors.initials: L
authors.lastname: Cubaynes
authors.forename: N
authors.initials: N
authors.lastname: Profizi
authors.forename: A
authors.initials: A
authors.lastname: Lafeuillade
authors.forename: B
authors.initials: B
authors.lastname: Marchou
authors.forename: P
authors.initials: P
authors.lastname: Massip
authors.forename: C
authors.initials: C
authors.lastname: Sayada
authors.forename: J
authors.initials: J
authors.lastname: Puel
mesh_terms: D000328:Adult; D001800:Blood Specimen Collection; D018791:CD4 Lymphocyte Count; D005260:Female; D016655:HIV Core Protein p24 / Q000097:blood; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000821:virology; D016133:Polymerase Chain Reaction / Q000379:methods*; D012367:RNA, Viral / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014766:Viremia / Q000821:virology
chemical_list: D016655:HIV Core Protein p24; D012367:RNA, Viral