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St. John E.P.,Roche Holding AG | Simen B.B.,Roche Holding AG | Simen B.B.,Blood Center Linz | Turenchalk G.S.,Roche Holding AG | And 50 more authors.
PLoS ONE | Year: 2016

Background. Ultra deep sequencing is of increasing use not only in research but also in diagnostics. For implementation of ultra deep sequencing assays in clinical laboratories for routine diagnostics, intra- and inter-laboratory testing are of the utmost importance. Methods. A multicenter study was conducted to validate an updated assay design for 454 Life Sciences' GS FLX Titanium system targeting protease/reverse transcriptase (RTP) and env (V3) regions to identify HIV-1 drug-resistance mutations and determine co-receptor use with high sensitivity. The study included 30 HIV-1 subtype B and 6 subtype non-B samples with viral titers (VT) of 3,940-447,400 copies/mL, two dilution series (52,129-1,340 and 25,130-734 copies/mL), and triplicate samples. Amplicons spanning PR codons 10-99, RT codons 1-251 and the entire V3 region were generated using barcoded primers. Analysis was performed using the GS Amplicon Variant Analyzer and geno2pheno for tropism. For comparison, population sequencing was performed using the ViroSeq HIV-1 genotyping system. Results The median sequencing depth across the 11 sites was 1,829 reads per position for RTP (IQR 592-3,488) and 2,410 for V3 (IQR 786-3,695). 10 preselected drug resistant variants were measured across sites and showed high inter-laboratory correlation across all sites with data (P<0.001). The triplicate samples of a plasmid mixture confirmed the high interlaboratory consistency (mean% ± stdev: 4.6 ±0.5, 4.8 ±0.4, 4.9 ±0.3) and revealed good intra-laboratory consistency (mean% range ± stdev range: 4.2-5.2 ± 0.04-0.65). In the two dilutions series, no variants >20% were missed, variants 2-10% were detected at most sites (even at low VT), and variants 1-2% were detected by some sites. All mutations detected by population sequencing were also detected by UDS. Conclusions This assay design results in an accurate and reproducible approach to analyze HIV-1 mutant spectra, even at variant frequencies well below those routinely detectable by population sequencing. Copyright © 2016 St. John et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Romero A.,CIBER ISCIII | Romero A.,Autonomous University of Barcelona | Sued O.,University of Barcelona | Puig T.,Institute Of Recerca Of La Sida Irsicaixa | And 37 more authors.
Enfermedades Infecciosas y Microbiologia Clinica | Year: 2011

Objectives: The objectives of this study were to assess the prevalence of transmitted HIV-1 drug resistances (TDR) and HIV-1 subtypes in recently infected patients in Catalonia between 2003 and 2005 and to describe the characteristics of these patients according to the presence or absence of TDR and HIV-1 subtype. Methods: After application of the Serological Testing Algorithm for Recent HIV Seroconversion (STARHS), residual aliquots of serum samples from recently infected antiretroviral-naïve individuals were genotyped. FASTA sequences were analyzed using the HIVDB Program. The World Health Organization 2009 List of Mutations for Surveillance of Transmitted HIV-1 Drug Resistant HIV Strains was used to estimate the prevalence of TDR. Results: Of 182 recently infected patients, 14 (7.7%) presented TDR. Seven (3.8%) had genotypic evidence of TDR against non-nucleoside reverse transcriptase inhibitors, 6 (3.3%) against nucleoside reverse transcriptase inhibitors, 3 (1.6%) against protease inhibitors (PIs), and only 2 individuals (1.1%) presented TDR against more than one class of drugs. Thirty-five (19.2%) patients were infected with a non-B HIV-1 subtype. Conclusion: This is the first study to estimate the prevalence of TDR in recently infected patients in Catalonia. The results are similar to those of studies performed in other Spanish regions. Correct monitoring of these parameters requires systematic epidemiologic surveillance of transmitted resistance. © 2010 Elsevier España, S.L. All rights reserved.


Frentz D.,Rotterdam University | Boucher C.A.B.,Rotterdam University | Boucher C.A.B.,University Utrecht | Assel M.,University of Stuttgart | And 18 more authors.
PLoS ONE | Year: 2010

Background: Several decision support systems have been developed to interpret HIV-1 drug resistance genotyping results. This study compares the ability of the most commonly used systems (ANRS, Rega, and Stanford's HIVdb) to predict virological outcome at 12, 24, and 48 weeks. Methodology/Principal Findings: Included were 3763 treatment-change episodes (TCEs) for which a HIV-1 genotype was available at the time of changing treatment with at least one follow-up viral load measurement. Genotypic susceptibility scores for the active regimens were calculated using scores defined by each interpretation system. Using logistic regression, we determined the association between the genotypic susceptibility score and proportion of TCEs having an undetectable viral load (<50 copies/ml) at 12 (8-16) weeks (2152 TCEs), 24 (16-32) weeks (2570 TCEs), and 48 (44-52) weeks (1083 TCEs). The Area under the ROC curve was calculated using a 10-fold cross-validation to compare the different interpretation systems regarding the sensitivity and specificity for predicting undetectable viral load. The mean genotypic susceptibility score of the systems was slightly smaller for HIVdb, with 1.92±1.17, compared to Rega and ANRS, with 2.22±1.09 and 2.23±1.05, respectively. However, similar odds ratio's were found for the association between each-unit increase in genotypic susceptibility score and undetectable viral load at week 12; 1.6 [95% confidence interval 1.5-1.7] for HIVdb, 1.7 [1.5-1.8] for ANRS, and 1.7 [1.9-1.6] for Rega. Odds ratio's increased over time, but remained comparable (odds ratio's ranging between 1.9-2.1 at 24 weeks and 1.9-2.2 at 48 weeks). The Area under the curve of the ROC did not differ between the systems at all time points; p = 0.60 at week 12, p = 0.71 at week 24, and p = 0.97 at week 48. Conclusions/Significance: Three commonly used HIV drug resistance interpretation systems ANRS, Rega and HIVdb predict virological response at 12, 24, and 48 weeks, after change of treatment to the same extent. © 2010 Frentz et al.


Beliakova-Bethell N.,University of California at San Diego | Massanella M.,Institute Of Recerca Of La Sida Irsicaixa | Massanella M.,University of California at San Diego | White C.,University of California at San Diego | And 9 more authors.
Cytometry Part A | Year: 2014

Multiple scientific disciplines require the isolation of specific subsets of blood cells from patient samples for gene expression analysis by microarray or RNA-sequencing, preserving disease- or treatment-related signatures. However, little is known with respect to the impact of different cell isolation methods on gene expression and the effects of positive selection, negative selection, and fluorescence activated cell sorting (FACS) have not previously been assessed in parallel. To address this knowledge gap, CD4+ T cells, CD8+ T cells, B cells, and monocytes were isolated from blood samples from five independent donors using positive immunomagnetic selection, negative immunomagnetic selection, and FACS. We hypothesized that positive selection and FACS would yield higher purity but may have an impact on gene expression since both methods utilize antibodies that bind surface receptors of the cell type of interest. Moreover, FACS might upregulate stress response genes due to passage of the cells through the sorter. Microarray gene expression data were generated and subjected to unsupervised clustering and differential gene expression analysis. Surprisingly, these analyses revealed that gene expression signatures were more similar between cells isolated by negative selection and FACS compared to cells isolated by positive selection. Moreover, genes that are involved in the response to stress generally had the highest expression in cells isolated by negative or positive selection and not FACS. Thus, FACS is the recommended method for isolation of leukocyte subsets for gene expression studies since this method results in the purest subset populations and does not appear to induce a stress response. © 2013 International Society for Advancement of Cytometry.

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