scholarly journals Sequencing-Based Detection of Low-Frequency Human Immunodeficiency Virus Type 1 Drug-Resistant Mutants by an RNA/DNA Heteroduplex Generator-Tracking Assay

2004 ◽  
Vol 78 (13) ◽  
pp. 7112-7123 ◽  
Author(s):  
Amit Kapoor ◽  
Morris Jones ◽  
R. W. Shafer ◽  
Soo-Yon Rhee ◽  
Powel Kazanjian ◽  
...  

ABSTRACT Drug-resistant viruses may be present as minority variants during early treatment failures or following discontinuation of failed antiretroviral regimens. A limitation of the traditional direct PCR population sequencing method is its inability to detect human immunodeficiency virus type 1 (HIV-1) variants present at frequencies lower than 20%. A drug resistance genotyping assay based on the isolation and DNA sequencing of minority HIV protease variants is presented here. A multiple-codon-specific heteroduplex generator probe was constructed to improve the separation of HIV protease genes varying in sequence at 12 codons associated with resistance to protease inhibitors. Using an RNA molecule as probe allowed the simple sequencing of protease variants isolated as RNA/DNA heteroduplexes with different electrophoretic mobilities. The protease gene RNA heteroduplex generator-tracking assay (RNA-HTA) was tested on plasma quasispecies from 21 HIV-1-infected persons in whom one or more protease resistance mutations emerged during therapy or following initiation of salvage regimens. In 11 of 21 cases, RNA-HTA testing of virus from the first episode of virologic failure identified protease resistance mutations not seen by population-based PCR sequencing. In 8 of these 11 cases, all of the low-frequency drug resistance mutations detected exclusively by RNA-HTA during the first episode became detectable by population-based PCR sequencing at the later time point. Distinct sets of protease mutations could be linked on different genomes in patients with high-frequency protease gene lineages. The enhanced detection of minority drug resistance variants using a sequencing-based assay may improve the efficacy of genotype-assisted salvage therapies.

2007 ◽  
Vol 14 (10) ◽  
pp. 1266-1273 ◽  
Author(s):  
Golo Ahlenstiel ◽  
Kirsten Roomp ◽  
Martin Däumer ◽  
Jacob Nattermann ◽  
Martin Vogel ◽  
...  

ABSTRACT The objective of this study was a comprehensive analysis of the immune-driven evolution of viruses of human immunodeficiency virus type 1 (HIV-1) clade B in a large patient cohort treated at a single hospital in Germany and its implications for antiretroviral therapy. We examined the association of the HLA-A, HLA-B, and HLA-DRB1 alleles with the emergence of mutations in the complete protease gene and the first 330 codons of the reverse transcriptase (RT) gene of HIV-1, studying their distribution and persistence and their impact on antiviral drug therapy. The clinical data for 179 HIV-infected patients, the results of HLA genotyping, and virus sequences were analyzed using a variety of statistical approaches. We describe new HLA-associated mutations in both viral protease and RT, several of which are associated with HLA-DRB1. The mutations reported are remarkably persistent within our cohort, developing more slowly in a minority of patients. Interestingly, several HLA-associated mutations occur at the same positions as drug resistance mutations in patient viruses, where the viral sequence was acquired before exposure to these drugs. The influence of HLA on thymidine analogue mutation pathways was not observed. We were able to confirm immune-driven selection pressure by major histocompatibility complex (MHC) class I and II alleles through the identification of HLA-associated mutations. HLA-B alleles were involved in more associations (68%) than either HLA-A (23%) or HLA-DRB1 (9%). As several of the HLA-associated mutations lie at positions associated with drug resistance, our results indicate possible negative effects of HLA genotypes on the development of HIV-1 drug resistance.


2021 ◽  
Vol 1 (1) ◽  
pp. 113-123
Author(s):  
Ahmad A. Hachem ◽  
Essa H. Hariri ◽  
Anthony Mansour ◽  
Jacques Mokhbat

Background: Antiretroviral drug resistance remains a significant problem in the clinical management of patients infected with the Human Immunodeficiency Virus type-1. Aim: This study investigates and reports data on the molecular characterization of HIV-1 isolates from patients who are in a state of therapy failure. Methods: This is a retrospective study conducted on 65 patients in therapy failure. Inclusion criteria included patients diagnosed as being in therapy failure between the years 2009 and 2013. We defined ART failure as either a failure to achieve viral suppression or a failure to detect viral loads below 500 copies/mL after virological suppression in at least two plasma samples.  We used the published WHO list for surveillance of transmitted resistance and the Stanford HIV Drug Resistance Database to identify drug resistance mutations. Results: 65% of the participants had at least one drug resistance mutation (DRM). 12% of the population sampled had resistance to only one ART class, 32% presented with resistance to two classes of antiretroviral drugs, and 20% had resistance to all three classes of drugs. The prevalence of nucleoside transcriptase inhibitor (NRTI) mutations was 55%, the most common DRM being M184V. The prevalence of non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations was 58%, with the most common mutation being the K103N mutation. The prevalence of protease inhibitors drug resistance mutations was 23%, with mutations V82A and I47V being present in 10% of the study population. Conclusion: Our study is the first molecular characterization of DRM emergence in HIV-1 strains from patients failing antiretroviral therapy in Lebanon. Continuous monitoring of resistance patterns for HIV in the country is necessary to tackle the emergent drug resistance.


2002 ◽  
Vol 76 (18) ◽  
pp. 9253-9259 ◽  
Author(s):  
Louis M. Mansky ◽  
Dennis K. Pearl ◽  
Lisa C. Gajary

ABSTRACT Replication of drug-resistant human immunodeficiency virus type 1 (HIV-1) in the presence of drug can lead to the failure of antiretroviral drug treatment. Drug failure is associated with the accumulation of drug resistance mutations. Previous studies have shown that 3′-azido-3′-deoxythymidine (AZT), (−)2′,3′-dideoxy-3′-thiacytidine (3TC), and AZT-resistant HIV-1 reverse transcriptase (RT) can increase the virus in vivo mutation rate. In this study, the combined effects of drug-resistant RT and antiretroviral drugs on the HIV-1 mutant frequency were determined. In most cases, a multiplicative effect was observed with AZT-resistant or AZT/3TC dually resistant RT and several drugs (i.e., AZT, 3TC, hydroxyurea, and thymidine) and led to increases in the odds of recovering virus mutants to over 20 times that of the HIV-1 mutant frequency in the absence of drug or drug-resistance mutations. This observation indicates that HIV-1 can mutate at a significantly higher rate when drug-resistant virus replicates in the presence of drug. These increased mutant frequencies could have important implications for HIV-1 population dynamics and drug therapy regimens.


2007 ◽  
Vol 81 (6) ◽  
pp. 2887-2898 ◽  
Author(s):  
Sandra M. Mueller ◽  
Birgit Schaetz ◽  
Kathrin Eismann ◽  
Silke Bergmann ◽  
Michael Bauerle ◽  
...  

ABSTRACT To determine the influence of human immunodeficiency virus type 1 (HIV-1)-specific CD8+ T cells on the development of drug resistance mutations in the HIV-1 protease, we analyzed protease sequences from viruses from a human leukocyte antigen class I (HLA class I)-typed cohort of 94 HIV-1-positive individuals. In univariate statistical analyses (Fisher's exact test), minor and major drug resistance mutations as well as drug-associated polymorphisms showed associations with HLA class I alleles. All correlations with P values of 0.05 or less were considered to be relevant without corrections for multiple tests. A subset of these observed correlations was experimentally validated by enzyme-linked immunospot assays, allowing the definition of 10 new epitopes recognized by CD8+ T cells from patients with the appropriate HLA class I type. Several drug resistance-associated mutations in the protease acted as escape mutations; however, cells from many patients were still able to generate CD8+ T cells targeting the escape mutants. This result presumably indicates the usage of different T-cell receptors by CD8+ T cells targeting these epitopes in these patients. Our results support a fundamental role for HLA class I-restricted immune responses in shaping the sequence of the HIV-1 protease in vivo. This role may have important clinical implications both for the understanding of drug resistance pathways and for the design of therapeutic vaccines targeting drug-resistant HIV-1.


2004 ◽  
Vol 48 (5) ◽  
pp. 1570-1580 ◽  
Author(s):  
Giada A. Locatelli ◽  
Giuseppe Campiani ◽  
Reynel Cancio ◽  
Elena Morelli ◽  
Anna Ramunno ◽  
...  

ABSTRACT We have previously described a novel class of nonnucleoside reverse transcriptase (RT) inhibitors, the pyrrolobenzoxazepinone (PBO) and the pyridopyrrolooxazepinone (PPO) derivatives, which were effective inhibitors of human immunodeficiency virus type 1 (HIV-1) RT, either wild type or carrying known drug resistance mutations (G. Campiani et al., J. Med. Chem. 42:4462-4470, 1999). The lead compound of the PPO class, (R)-(−)-PPO464, was shown to selectively target the ternary complex formed by the viral RT with its substrates nucleic acid and nucleotide (G. Maga et al., J. Biol. Chem. 276:44653-44662, 2001). In order to better understand the structural basis for this selectivity, we exploited some PBO analogs characterized by various substituents at C-3 and by different inhibition potencies and drug resistance profiles, and we studied their interaction with HIV-1 RT wild type or carrying the drug resistance mutations L100I and V106A. Our kinetic and thermodynamic analyses showed that the formation of the complex between the enzyme and the nucleotide increased the inhibition potency of the compound PBO354 and shifted the free energy (energy of activation, ΔG#) for inhibitor binding toward more negative values. The V106A mutation conferred resistance to PBO 354 by increasing its dissociation rate from the enzyme, whereas the L100I mutation mainly decreased the association rate. This latter mutation also caused a severe reduction in the catalytic efficiency of the RT. These results provide a correlation between the efficiency of nucleotide utilization by RT and its resistance to PBO inhibition.


2000 ◽  
Vol 38 (11) ◽  
pp. 3919-3925 ◽  
Author(s):  
Laurence Vergne ◽  
Martine Peeters ◽  
Eitel Mpoudi-Ngole ◽  
Anke Bourgeois ◽  
Florian Liegeois ◽  
...  

Most human immunodeficiency virus (HIV) drug susceptibility studies have involved subtype B strains. Little information on the impact of viral diversity on natural susceptibility to antiretroviral drugs has been reported. However, the prevalence of non-subtype-B (non-B) HIV type 1 (HIV-1) strains continues to increase in industrialized countries, and antiretroviral treatments have recently become available in certain developing countries where non-B subtypes predominate. We sequenced the protease and reverse transcriptase (RT) genes of 142 HIV-1 isolates from antiretroviral-naive patients: 4 belonged to group O and 138 belonged to group M (9 subtype A, 13 subtype B, 2 subtype C, 5 subtype D, 2 subtype F1, 9 subtype F2, 4 subtype G, 5 subtype J, 2 subtype K, 3 subtype CRF01-AE, 67 subtype CRF02-AG, and 17 unclassified isolates). No major mutations associated with resistance to nucleoside reverse transcriptase inhibitors (NRTIs) or protease inhibitors were detected. Major mutations linked to resistance to non-NRTI agents were detected in all group O isolates (A98G and Y181C) and in one subtype J virus (V108I). In contrast, many accessory mutations were found, especially in the protease gene. Only 5.6% of the 142 strains, all belonging to subtype B or D, had no mutations in the protease gene. Sixty percent had one mutation, 22.5% had two mutations, 9.8% had three mutations, and 2.1% (all group O strains) had four mutations. In order of decreasing frequency, the following mutations were identified in the protease gene: M36I (86.6%), L10I/V (26%), L63P (12.6%), K20M/R (11.2%), V77I (5.6%), A71V (2.8%), L33F (0.7%), and M46I (0.7%). R211K, an accessory mutation associated with NRTI resistance, was also observed in 43.6% of the samples. Phenotypic and clinical studies are now required to determine whether multidrug-resistant viruses emerge more rapidly during antiretroviral therapy when minor resistance-conferring mutations are present before treatment initiation.


2020 ◽  
Vol 17 ◽  
Author(s):  
Behzad Dehghani ◽  
Zahra Hasanshahi ◽  
Tayebeh Hashempour ◽  
Parvin Afsar Kazerooni

Background: The rate of Human Immunodeficiency Virus type 1 (HIV-1) infection in Iran has increased dramatically in the last few years. Objective: The aim of this study was to investigate the HIV subtype amongst all Iranian HIV sequences, using 8 online websites. Methods: In this study, 637 sequences of polymerase, and gag genes of HIV-1 were obtained from NCBI. HIV-1 subtyping was done, using 8 reliable software. Results: The final results of the 8 online tools indicated that the majority of sequences were HIV-1 subtype CRF35 AD. However, it appeared that in some genes a few programs could not determine specific subtypes and in some cases they described different subtypes. Conclusion: Considering the CRF35 AD diagram, it was clear that integrase was not an appropriate region to define this subtype. Also the full length of gag gene should be used for subtyping. For CRF1, AE envelop gene is a reliable region to define this subtype. Stanford software was used to determine the drug resistance prevalence and in 5.7% of the sequences, drug resistance mutations were found.


2009 ◽  
Vol 53 (7) ◽  
pp. 2965-2973 ◽  
Author(s):  
Andrea Hauser ◽  
Kizito Mugenyi ◽  
Rose Kabasinguzi ◽  
Kerstin Bluethgen ◽  
Claudia Kuecherer ◽  
...  

ABSTRACTNevirapine (single dose), commonly used to prevent the mother-to-child transmission of human immunodeficiency virus (HIV) in developing countries, frequently induces viral resistance. Even mutations which occur only in a minor population of the HIV quasispecies (<20%) are associated with subsequent treatment failure but cannot be detected by population-based sequencing. We developed sensitive allele-specific real-time PCR (ASPCR) assays for two key resistance mutations of nevirapine. The assays were specifically designed to analyze HIV-1 subtype A and D isolates accounting for the majority of HIV infections in Uganda. Assays were evaluated using DNA standards and clinical samples of Ugandan women having preventively taken single-dose nevirapine. Lower detection limits of drug-resistant HIV type 1 (HIV-1) variants carrying reverse transcriptase mutations were 0.019% (K103N [AAC]), 0.013% (K103N [AAT]), and 0.29% (Y181C [TGT]), respectively. Accuracy and precision were high, with coefficients of variation (the standard ratio divided by the mean) of 0.02 to 0.15 for intra-assay variability and those of 0.07 to 0.15 (K103N) and 0.28 to 0.52 (Y181C) for inter-assay variability. ASPCR assays enabled the additional identification of 12 (20%) minor drug-resistant HIV variants in the 20 clinical Ugandan samples (3 mutation analyses per patient; 60 analyses in total) which were not detectable by population-based sequencing. The individual patient cutoff derived from the clinical baseline sample was more appropriate than the standard-based cutoff from cloned DNA. The latter is a suitable alternative since the presence/absence of drug-resistant HIV-1 strains was concordantly identified in 92% (55/60) of the analyses. These assays are useful to monitor the emergence and persistence of drug-resistant HIV-1 variants in subjects infected with HIV-1 subtypes A and D.


1999 ◽  
Vol 37 (7) ◽  
pp. 2291-2296 ◽  
Author(s):  
Rob Schuurman ◽  
Lisa Demeter ◽  
Patricia Reichelderfer ◽  
Jolanda Tijnagel ◽  
Tom de Groot ◽  
...  

A panel (ENVA-1) of well-defined blinded samples containing wild-type and mutant human immunodeficiency virus type 1 (HIV-1) reverse transcriptase was analyzed by automated DNA sequencing in 23 laboratories worldwide. Drug resistance mutations at codons 41, 215, and 184 were present in the panel samples at different ratios to the wild type. The presence of mutant genotypes was determined qualitatively and quantitatively. All laboratories reported the presence of sequence heterogeneities at codons 41, 215, and 184 in one or more of the panel samples, though not all reported the correct codon genotypes. Two laboratories reported a mutant genotype in samples containing only the wild type, whereas two and three laboratories failed to detect the mutant genotypes at codons 41 and 215, respectively, in a completely mutant DNA population. Mutations present at relative concentrations of 25% of the total DNA population were successfully identified by 13 of 23, 10 of 23, and 16 of 23 labs for codons 41, 215, and 184Val, respectively. For more than 80% of those laboratories that qualitatively detected the presence of a mutation correctly, the estimated wild type/mutant ratio was less than 25% different from the input ratio in those samples containing 25 to 50% or 75% mutant input. This first multicenter study on the quality of DNA sequencing approaches for identifying HIV-1 drug resistance mutations revealed large interlaboratory differences in the quality of the results. The application of these procedures in their current state would in several cases lead to inaccurate or even incorrect diagnostic results. Therefore, proper quality control and standardization are urgently needed.


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