Abstract

Total HIV-1 DNA has been shown to reflect reservoir size in HIV-1 infected individuals and correlate with viral rebound time after therapy interruption. Quantification of total HIV-1 DNA level may be used to study and evaluate reservoir elimination therapies. There is currently no FDA approved HIV- 1 DNA quantification assay available. The performance of a research uses only kit, Ultrabio HIV DNA quantification kit, was compared to a commonly used laboratory qPCR method targeting the gag region (GAG PCR). The limit of detection (LOD) and precision was evaluated with serially diluted 8E5/LAV DNA. LOD of Ultrabio Kit and GAG PCR was determined to be 4 and 25 copies/reaction, respectively. The Ultrabio Kit showed less variation when HIV-1 DNA concentration was lower than 20 copies/reaction. Twentysix HIV-1 infected patients’ PBMCs samples were quantified by both methods and the Ultrabio kit showed higher sensitivity. GAG PCR was unable to detect 2 of the samples while Ultrabio Kit was able to detect all. Both 2 samples had undetectable viral load. The quantified HIV DNA copies/million cells of the 24 detected samples by both methods showed good correlation, r=0.91. The difference was within one log.

Keywords: HIV-1 total DNA; real-time PCR; HIV-1 DNA reservoir; GAG real-time PCR; Quantification