Sensitive cell-based assay for determination of human immunodeficiency virus type 1 coreceptor tropism
Jazyk angličtina Země Spojené státy americké Médium print-electronic
Typ dokumentu hodnotící studie, časopisecké články, Research Support, N.I.H., Extramural, práce podpořená grantem
Grantová podpora
P30 AI036219
NIAID NIH HHS - United States
R01 AI049170
NIAID NIH HHS - United States
BB/H012419/1
Biotechnology and Biological Sciences Research Council - United Kingdom
PubMed
23486708
PubMed Central
PMC3647936
DOI
10.1128/jcm.00092-13
PII: JCM.00092-13
Knihovny.cz E-zdroje
- MeSH
- buněčné linie MeSH
- cyklohexany MeSH
- fúze buněk MeSH
- genom virový MeSH
- genotyp MeSH
- genové produkty env - virus lidské imunodeficience genetika MeSH
- HEK293 buňky MeSH
- HIV infekce farmakoterapie virologie MeSH
- HIV-1 fyziologie MeSH
- látky proti HIV farmakologie MeSH
- lidé MeSH
- maravirok MeSH
- pilotní projekty MeSH
- receptory CCR5 genetika MeSH
- receptory CXCR4 genetika MeSH
- receptory HIV antagonisté a inhibitory metabolismus MeSH
- RNA virová genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika MeSH
- senzitivita a specificita MeSH
- triazoly MeSH
- tropismus virů * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- CXCR4 protein, human MeSH Prohlížeč
- cyklohexany MeSH
- genové produkty env - virus lidské imunodeficience MeSH
- látky proti HIV MeSH
- maravirok MeSH
- receptory CCR5 MeSH
- receptory CXCR4 MeSH
- receptory HIV MeSH
- RNA virová MeSH
- Saccharomyces cerevisiae - proteiny MeSH
- triazoly MeSH
- URA3 protein, S cerevisiae MeSH Prohlížeč
CCR5 antagonists are a powerful new class of antiretroviral drugs that require a companion assay to evaluate the presence of CXCR4-tropic (non-R5) viruses prior to use in human immunodeficiency virus (HIV)-infected individuals. In this study, we have developed, characterized, verified, and prevalidated a novel phenotypic test to determine HIV-1 coreceptor tropism (VERITROP) based on a sensitive cell-to-cell fusion assay. A proprietary vector was constructed containing a near-full-length HIV-1 genome with the yeast uracil biosynthesis (URA3) gene replacing the HIV-1 env coding sequence. Patient-derived HIV-1 PCR products were introduced by homologous recombination using an innovative yeast-based cloning strategy. The env-expressing vectors were then used in a cell-to-cell fusion assay to determine the presence of R5 and/or non-R5 HIV-1 variants within the viral population. Results were compared with (i) the original version of Trofile (Monogram Biosciences, San Francisco, CA), (ii) population sequencing, and (iii) 454 pyrosequencing, with the genotypic data analyzed using several bioinformatics tools, i.e., the 11/24/25 rule, Geno2Pheno (2% to 5.75%, 3.5%, or 10% false-positive rate [FPR]), and webPSSM. VERITROP consistently detected minority non-R5 variants from clinical specimens, with an analytical sensitivity of 0.3%, with viral loads of ≥1,000 copies/ml, and from B and non-B subtypes. In a pilot study, a 73.7% (56/76) concordance was observed with the original Trofile assay, with 19 of the 20 discordant results corresponding to non-R5 variants detected using VERITROP and not by the original Trofile assay. The degree of concordance of VERITROP and Trofile with population and deep sequencing results depended on the algorithm used to determine HIV-1 coreceptor tropism. Overall, VERITROP showed better concordance with deep sequencing/Geno2Pheno at a 0.3% detection threshold (67%), whereas Trofile matched better with population sequencing (79%). However, 454 sequencing using Geno2Pheno at a 10% FPR and 0.3% threshold and VERITROP more accurately predicted the success of a maraviroc-based regimen. In conclusion, VERITROP may promote the development of new HIV coreceptor antagonists and aid in the treatment and management of HIV-infected individuals prior to and/or during treatment with this class of drugs.
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