BACKGROUND: In France, HIV infection diagnosis was modified by a decree, published in 2010, that requires the use of HIV Ag/Ab assays able to detect at least 2 IU/ml of p24Ag. This measure raises the concern of the capacity of these assays to equally detect all HIV variants. OBJECTIVES: To assess the performance of HIV Ag/Ab assays for the detection of p24Ag from diverse HIV isolates. STUDY DESIGN: Ten HIV Ag/Ab assays were compared using two p24Ag reference standards, 297 samples from 99 HIV-1 and HIV-2 cell-culture derived isolates including various subtypes and groups, and 9 native specimens from subjects with primary HIV infection. RESULTS: The p24Ag limit of detection (LOD) ranged from 0.505 IU/ml to 1.90 1 IU/ml and, from 11.9 pg/ml to 33.5 pg/ml when using WHO and French national standards, respectively. The overall percentage of positive samples ranged from 26.8% to 74.5%. Five assays failed to detect all dilutions of at least one group M subtype, three missed all group O and six all the group P samples. Three assays were able to detect 2-10 of the 30 HIV-2 samples. The distribution of LODs for each group M isolate showed a wide dispersion between the assays. Percentage of isolates detected at a p24Ag level less than 2 IU/ml varied from 22% to 98.7%. CONCLUSION: This study demonstrated that, even though their analytical sensitivity fulfills the requirements, many of HIV Ag/Ab assays could fail to detect HIV primary infection due to HIV-1 non-B, non-M and HIV-2 strains.
BACKGROUND: In France, HIV infection diagnosis was modified by a decree, published in 2010, that requires the use of HIV Ag/Ab assays able to detect at least 2 IU/ml of p24Ag. This measure raises the concern of the capacity of these assays to equally detect all HIV variants. OBJECTIVES: To assess the performance of HIV Ag/Ab assays for the detection of p24Ag from diverse HIV isolates. STUDY DESIGN: Ten HIV Ag/Ab assays were compared using two p24Ag reference standards, 297 samples from 99 HIV-1 and HIV-2 cell-culture derived isolates including various subtypes and groups, and 9 native specimens from subjects with primary HIV infection. RESULTS: The p24Ag limit of detection (LOD) ranged from 0.505 IU/ml to 1.90 1 IU/ml and, from 11.9 pg/ml to 33.5 pg/ml when using WHO and French national standards, respectively. The overall percentage of positive samples ranged from 26.8% to 74.5%. Five assays failed to detect all dilutions of at least one group M subtype, three missed all group O and six all the group P samples. Three assays were able to detect 2-10 of the 30 HIV-2 samples. The distribution of LODs for each group M isolate showed a wide dispersion between the assays. Percentage of isolates detected at a p24Ag level less than 2 IU/ml varied from 22% to 98.7%. CONCLUSION: This study demonstrated that, even though their analytical sensitivity fulfills the requirements, many of HIV Ag/Ab assays could fail to detect HIV primary infection due to HIV-1 non-B, non-M and HIV-2 strains.
Authors: Ana M Sanchez; C Todd DeMarco; Bhavna Hora; Sarah Keinonen; Yue Chen; Christie Brinkley; Mars Stone; Leslie Tobler; Sheila Keating; Marco Schito; Michael P Busch; Feng Gao; Thomas N Denny Journal: J Immunol Methods Date: 2014-01-19 Impact factor: 2.303
Authors: Eleanor R Gray; Robert Bain; Olivia Varsaneux; Rosanna W Peeling; Molly M Stevens; Rachel A McKendry Journal: AIDS Date: 2018-09-24 Impact factor: 4.177