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Abstract: Background: Clinical trials of CCR5 antagonists have relied on the phenotypic determination of HIV-1 coreceptor usage. Few phenotypic assays are available, with few data on their concordance, and none has been designed to determine tropism from cell-associated HIV-1 DNA. Objectives: To assess the performance of the new Toulouse Tropism Test (TTT) phenotypic assay to characterize HIV-1 tropism using blood plasma and peripheral blood mononuclear cells (PBMC). Study design: 434 plasma and 168 PBMC samples were tested with the TTT assay. We determined the correlation between our assay results on plasma samples and those of the commercial Trofile™ assay. Results: The TTT assay determined the tropism of 97% of samples after successful amplification of the env gene. It performed well on both cell samples and plasma samples with various HIV-1 loads and subtypes. It detected 0.5% of minor CXCR4-using variants in the virus population. The TTT and the Trofile™ assays were >90% concordant for predicting HIV-1 tropism. Conclusion: We have validated a new recombinant virus phenotypic assay for determining HIV-1 tropism using both plasma and cell samples from patients who are candidates for treatment with CCR5 antagonists. [Copyright &y& Elsevier]

Persistent infection with high-risk human papillomavirus (HPV-HR) is a recognized cause of cervical cancer. The aimof this studywas to compare analytical and clinical performances of the Cobas®HPV and Anyplex™ II HPV28 assays for HPV detection and genotyping. A total of 94 cervical samples were tested. For HPV-HR, the results agreed very well (94.68%),with 100% agreement when detecting CIN2+. The Anyplex™ II HPV28 assay detected more genotypes than the Cobas® HPV Test, but their clinical performances were similar. [ABSTRACT FROM AUTHOR]

• Efficient testing is required to control the rapid spread of the SARS-CoV-2 virus. • We conducted a prospective study assessing individual and pooled saliva sensitivity. • Saliva-based tests are sensitive and may increase patient adherence with screening. • Mass screening of pools of five specimens is a strategy worth considering. Control of the rapid spread of the SARS-CoV-2 virus requires efficient testing. We collected paired nasopharyngeal swab (NPs) and saliva samples from 303 subjects (52.8% symptomatic) at a drive-through testing center; 18% of whom tested positive. The NPs, salivas and five saliva pools were tested for SARS-CoV-2 RNA using the Aptima™ assay and a laboratory-developed test (LDT) on the Panther-Fusion™ Hologic® platform. The saliva sensitivity was 80% (LDT) and 87.5% (Aptima™) whereas that of NPs was 96.4% in both assays. The pooled saliva sensitivity of 72.7% (LDT) and 75% (Aptima™) was not significantly different of that of individual saliva testing. Saliva specimens appear to be suitable for sensitive non-invasive assays to detect SARS-CoV-2 nucleic acid; pooling them for a single test will improve laboratory throughput. [ABSTRACT FROM AUTHOR]

Quantification of HBV DNA is used for initiating and monitoring antiviral treatment. We have evaluated the Xpert HBV Viral Load (VL) assay on the GeneXpert instrument. We estimated its limit of detection to be 7.5 IU/mL. Reproducibility was 1.1–12.7% as assessed by the coefficients of variation for 3 different samples. The assay was linear from 2 to 8 log 10 IU/mL for HBV genotypes A to F. Its clinical performance was evaluated by testing prospectively 100 HBV DNA-positive samples with the Xpert HBV VL and Aptima Quant HBV assays. The results from the 2 assays were correlated, with a modest bias (−0.10 log 10 IU/mL) between them by Bland–Altman analysis. Patient monitoring with 80 samples performed with both assays gave similar patient profiles with trends in the same direction. The Xpert HBV Viral load assay is reliable enough for quantifying HBV DNA in clinical practice. [ABSTRACT FROM AUTHOR]