title: An international collaboration to standardize HIV-2 viral load assays: results from the 2009 ACHI(E)V(2E) quality control study.
abstract: Accurate HIV-2 plasma viral load quantification is crucial for adequate HIV-2 patient management and for the proper conduct of clinical trials and international cohort collaborations. This study compared the homogeneity of HIV-2 RNA quantification when using HIV-2 assays from ACHI(E)V(2E) study sites and either in-house PCR calibration standards or common viral load standards supplied to all collaborators. Each of the 12 participating laboratories quantified blinded HIV-2 samples, using its own HIV-2 viral load assay and standard as well as centrally validated and distributed common HIV-2 group A and B standards (http://www.hiv.lanl.gov/content/sequence/HelpDocs/subtypes-more.html). Aliquots of HIV-2 group A and B strains, each at 2 theoretical concentrations (2.7 and 3.7 log(10) copies/ml), were tested. Intralaboratory, interlaboratory, and overall variances of quantification results obtained with both standards were compared using F tests. For HIV-2 group A quantifications, overall and interlaboratory and/or intralaboratory variances were significantly lower when using the common standard than when using in-house standards at the concentration levels of 2.7 log(10) copies/ml and 3.7 log(10) copies/ml, respectively. For HIV-2 group B, a high heterogeneity was observed and the variances did not differ according to the type of standard used. In this international collaboration, the use of a common standard improved the homogeneity of HIV-2 group A RNA quantification only. The diversity of HIV-2 group B, particularly in PCR primer-binding regions, may explain the heterogeneity in quantification of this strain. Development of a validated HIV-2 viral load assay that accurately quantifies distinct circulating strains is needed.
authors.affiliation: APHP, Hôpital Bichat-Claude Bernard, Laboratoire de Virologie, Paris F-75018, France. florence.damond@bch.aphp.fr
authors.forename: F
authors.initials: F
authors.lastname: Damond
authors.forename: A
authors.initials: A
authors.lastname: Benard
authors.forename: Claudia
authors.initials: C
authors.lastname: Balotta
authors.forename: Jürg
authors.initials: J
authors.lastname: Böni
authors.forename: Matthew
authors.initials: M
authors.lastname: Cotten
authors.forename: Vitor
authors.initials: V
authors.lastname: Duque
authors.forename: Bridget
authors.initials: B
authors.lastname: Ferns
authors.forename: Jeremy
authors.initials: J
authors.lastname: Garson
authors.forename: Perpetua
authors.initials: P
authors.lastname: Gomes
authors.forename: Fátima
authors.initials: F
authors.lastname: Gonçalves
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Gottlieb
authors.forename: Bernd
authors.initials: B
authors.lastname: Kupfer
authors.forename: Jean
authors.initials: J
authors.lastname: Ruelle
authors.forename: Berta
authors.initials: B
authors.lastname: Rodes
authors.forename: Vicente
authors.initials: V
authors.lastname: Soriano
authors.forename: Mark
authors.initials: M
authors.lastname: Wainberg
authors.forename: Audrey
authors.initials: A
authors.lastname: Taieb
authors.forename: Sophie
authors.initials: S
authors.lastname: Matheron
authors.forename: Genevieve
authors.initials: G
authors.lastname: Chene
authors.forename: Francoise
authors.initials: F
authors.lastname: Brun-Vezinet
mesh_terms: D015658:HIV Infections / Q000821:virology*; D015498:HIV-2 / Q000302:isolation & purification*; D006801:Humans; D007391:International Cooperation; D015588:Observer Variation; D010949:Plasma / Q000821:virology; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D019562:Viral Load / Q000379:methods* / Q000592:standards