External quality assessment of HIV-1 DNA quantification assays used in the clinical setting in Italy

I. Vicenti, F. Dragoni, A. Giannini, A. Casabianca, F. Lombardi, L. Di Sante, O. Turriziani, S. Racca, S. Paolucci, A. Lai, I. Bon, I. Abbate, G. Rozera, S. Belmonti, R. Scutari, C. Alteri, F. Saladini, M. Zazzi, C. Orlandi, M. MagnaniS. Di Giambenedetto, R. Longo, S. Menzo, D. Di Carlo, L. Mazzuti, A. Ardemagni, M. Clementi, F. Baldanti, F. Giardina, A. Bergna, C. Balotta, A. Bertoldi, M.R. Capobianchi, F. Ceccherini-Silberstein, M. Antonello, C.F. Perno, M. Andreoni, Italian HIV DNA Network

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Total cell-associated HIV-1 DNA is a surrogate marker of the HIV-1 reservoir, however, certified systems for its quantification are not available. The Italian HIV DNA Network was launched to validate HIV-1 DNA quantification methods in use at University and Hospital labs. A quality control panel including HIV-1 DNA standards, reconstructed blood samples (RBSs) and DNA from different HIV-1 subtypes was blindly tested by 12 participating labs by quantitative real-time PCR (n = 6), droplet digital PCR (n = 3) or both (n = 3). The median 95% hit rate was 4.6 (3.7–5.5) copies per test and linearity in the tested range was excellent (R2 = 1.000 [1.000–1.000]). The median values obtained across labs were 3,370 (2,287–4,245), 445 (299–498), 59 (40–81) and 7 (6–11) HIV-1 DNA copies, for the 3,584, 448, 56 and 7-copy standards, respectively. With RBSs, measured values were within twofold with respect to the median in two thirds of cases. HIV-1 subtypes were missed (CRF01_AE by 3 labs) or underestimated by > 1 log (subtypes A, C, D, F by one lab; CRF01_AE by one lab; CRF02_AG by one lab). The overall performance was excellent with HIV-1 DNA standards, however detection of different HIV-1 subtypes must be improved.

Original languageItalian
Pages (from-to)1-11
Number of pages11
JournalScientific Reports
Issue number1
Publication statusPublished - 2022

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