scholarly journals HIV-1 Group O Integrase Displays Lower Enzymatic Efficiency and Higher Susceptibility to Raltegravir than HIV-1 Group M Subtype B Integrase

2014 ◽  
Vol 58 (12) ◽  
pp. 7141-7150 ◽  
Author(s):  
Agnès Depatureaux ◽  
Peter K. Quashie ◽  
Thibault Mesplède ◽  
Yingshan Han ◽  
Hannah Koubi ◽  
...  

ABSTRACTHIV-1 group O (HIV-O) is a rare HIV-1 variant characterized by a high number of polymorphisms, especially in the integrase coding region. As HIV-O integrase enzymes have not previously been studied, our aim was to assess the impact of HIV-O integrase polymorphisms on enzyme function and susceptibility to integrase inhibitors. Accordingly, we cloned and purified integrase proteins from each of HIV-1 group O clades A and B, an HIV-O divergent strain, and HIV-1 group M (HIV-M, subtype B), used as a reference. To assess enzymatic function of HIV-O integrase, we carried out strand transfer and 3′ processing assays with various concentrations of substrate (DNA target and long terminal repeats [LTR], respectively) and characterized these enzymes for susceptibility to integrase strand transfer inhibitors (INSTIs) in cell-free assays and in tissue culture, in the absence or presence of various concentrations of several INSTIs. The inhibition constant (Ki) and 50% effective concentration (EC50) values were calculated for HIV-O integrases and HIV-O viruses, respectively, and compared with those of HIV-M. The results showed that HIV-O integrase displayed lower activity in strand transfer assays than did HIV-M enzyme, whereas 3′ processing activities were similar to those of HIV-M. HIV-O integrases were more susceptible to raltegravir (RAL) in competitive inhibition assays and in tissue culture than were HIV-M enzymes and viruses, respectively. Molecular modeling suggests that two key polymorphic residues that are close to the integrase catalytic site, 74I and 153A, may play a role in these differences.

Acta Naturae ◽  
2015 ◽  
Vol 7 (1) ◽  
pp. 78-86 ◽  
Author(s):  
O. A. Shadrina ◽  
T. S. Zatsepin ◽  
Yu. Yu. Agapkina ◽  
M. G. Isaguliants ◽  
M. B. Gottikh

Integration of human immunodeficiency virus (HIV-1) DNA into the genome of an infected cell is one of the key steps in the viral replication cycle. The viral enzyme integrase (IN), which catalyzes the integration, is an attractive target for the development of new antiviral drugs. However, the HIV-1 therapy often results in the IN gene mutations inducing viral resistance to integration inhibitors. To assess the impact of drug resistance mutations on the activity of IN of HIV-1 subtype A strain FSU-A, which is dominant in Russia, variants of the consensus IN of this subtype containing the primary resistance mutations G118R and Q148K and secondary compensatory substitutions E138K and G140S were prepared and characterized. Comparative study of these enzymes with the corresponding mutants of IN of HIV-1 subtype B strains HXB-2 was performed. The mutation Q148K almost equally reduced the activity of integrases of both subtypes. Its negative effect was partially compensated by the secondary mutations E138K and G140S. Primary substitution G118R had different influence on the activity of proteins of the subtypes A and B, and the compensatory effect of the secondary substitution E138K also depended on the viral subtype. Comparison of the mutants resistance to the known strand transfer inhibitors raltegravir and elvitegravir, and a new inhibitor XZ-259 (a dihydro-1H-isoindol derivative), showed that integrases of both subtypes with the Q148K mutation were insensitive to raltegravir and elvitegravir but were effectively inhibited by XZ-259. The substitution G118R slightly reduced the efficiency of IN inhibition by raltegravir and elvitegravir and caused no resistance to XZ_259.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anna Prats ◽  
Ignacio Martínez-Zalacaín ◽  
Beatriz Mothe ◽  
Eugènia Negredo ◽  
Núria Pérez-Álvarez ◽  
...  

AbstractIntegrase strand transfer inhibitors (INSTI) are a main component of the current antiretroviral regimens recommended for treatment of HIV infection. However, little is known about the impact of INSTI on neurocognition and neuroimaging. We developed a prospective observational trial to evaluate the effects of INSTI-based antiretroviral therapy on comprehensive brain outcomes (cognitive, functional, and imaging) according to the time since HIV-1 acquisition. We recruited men living with HIV who initiated antiretroviral therapy with INSTI < 3 months since the estimated date of HIV-1 acquisition (n = 12) and > 6 months since estimated date of HIV-1 acquisition (n = 15). We also recruited a group of matched seronegative individuals (n = 15). Assessments were performed at baseline (before initiation of therapy in HIV arms) and at weeks 4 and 48. Baseline cognitive functioning was comparable between the arms. At week 48, we did not find cognitive differences between starting therapy with INSTI earlier than 3 months or later than 6 months after acquisition of HIV-1 infection. Functional status was poorer in individuals diagnosed earlier. This effect recovered 48 weeks after initiation of therapy. Regarding brain imaging, we found that men living with HIV initiating antiretroviral therapy later experienced a greater decrease in medial orbitofrontal cortex over time, with expected negative repercussions for decision-making tasks.


2014 ◽  
Vol 58 (8) ◽  
pp. 4515-4526 ◽  
Author(s):  
Hong-Tao Xu ◽  
Susan P. Colby-Germinario ◽  
Maureen Oliveira ◽  
Daniel Rajotte ◽  
Richard Bethell ◽  
...  

ABSTRACTA W153L substitution in HIV-1 reverse transcriptase (RT) was recently identified by selection with a novel nucleotide-competing RT inhibitor (NcRTI) termed compound A that is a member of the benzo[4,5]furo[3,2,d]pyrimidin-2-one NcRTI family of drugs. To investigate the impact of W153L, alone or in combination with the clinically relevant RT resistance substitutions K65R (change of Lys to Arg at position 65), M184I, K101E, K103N, E138K, and Y181C, on HIV-1 phenotypic susceptibility, viral replication, and RT enzymatic function, we generated recombinant RT enzymes and viruses containing each of these substitutions or various combinations of them. We found that W153L-containing viruses were impaired in viral replicative capacity and were hypersusceptible to tenofovir (TFV) while retaining susceptibility to most nonnucleoside RT inhibitors. The nucleoside 3TC retained potency against W153L-containing viruses but not when the M184I substitution was also present. W153L was also able to reverse the effects of the K65R substitution on resistance to TFV, and K65R conferred hypersusceptibility to compound A. Biochemical assays demonstrated that W153L alone or in combination with K65R, M184I, K101E, K103N, E138K, and Y181C impaired enzyme processivity and polymerization efficiency but did not diminish RNase H activity, providing mechanistic insights into the low replicative fitness associated with these substitutions. We show that the mechanism of the TFV hypersusceptibility conferred by W153L is mainly due to increased efficiency of TFV-diphosphate incorporation. These results demonstrate that compound A and/or derivatives thereof have the potential to be important antiretroviral agents that may be combined with tenofovir to achieve synergistic results.


Author(s):  
Young-Keol Cho ◽  
Jung-eun Kim ◽  
Brian Foley

The objective of this study is to investigate whether the sequence length of HIV-1 increases over time. A longitudinal analysis of full-length coding region sequences (FLs) in an outbreak of HIV-1 infection among patients with hemophilia and local controls identified as infected with the Korean subclade B of HIV-1 (KSB). Genes amplified by overlapping RT-PCR or nested PCR were subjected to direct sequencing. In total, 141 FLs were sequentially determined over 30 years in 62 KSB-infected patients. Non-KSB sequences were retrieved from the Los Alamos National Laboratory HIV Database. Phylogenetic analysis indicated that within KSB, 2 FLs from plasma donors O and P comprised two clusters together with 8 and 12 patients with hemophilia, respectively. Signature pattern analysis for the KSB of HIV-1 revealed signature nucleotide residues at 1.05%, compared with local controls. Additionally, in-depth FLs sequence analysis over 30 years in KSB indicates that the KSB FL significantly increases over time before combined antiretroviral therapy (cART) and decreases on cART. Furthermore, the increase in FLs over time significantly occurred in the subtypes B, C and G, but, there was no increase in the subtypes D, A, and F1. Consequently, subtypes F1 and D had the shortest sequence length. Our analysis was extended to compare HIV-1 with HIV-2 and SIVs. Essentially, the longer the sequence length (SIVsm &gt; HIV-2 &gt; SIVcpz &gt; HIV-1), the longer the survival period. The increase in the length of the HIV-1 sequence over time suggests that it might be an evolutionary direction toward attenuated pathogenicity.


2020 ◽  
Vol 76 (1) ◽  
pp. 124-129
Author(s):  
Benjamin M Wenk ◽  
Herbert A Mbunkah ◽  
Ndi N Nsanwe ◽  
Eyongetah T Mbu ◽  
Lydia M Besong ◽  
...  

Abstract Objectives In Cameroon, the integrase (IN) strand transfer inhibitor (INSTI) dolutegravir was recently introduced for the treatment of HIV-1 infection. Since pretreatment HIV-1 drug resistance can jeopardize the success of ART, and considering the high heterogeneity of circulating HIV-1 subtypes in Cameroon, we investigated the prevalence of pretreatment HIV-1 resistance to INSTIs. Methods Fingerprick dried blood spot samples were collected from 339 newly diagnosed HIV-1-infected individuals between 2015 and 2016 in four hospitals in Cameroon. Universal primers were designed to amplify the HIV-1 IN region from amino acid 1 to 276. Amplicons were sequenced with Illumina next-generation sequencing and analysed with the Polymorphism Analysis Sequencing (PASeq) platform, using the Stanford HIV Drug Resistance Database to interpret HIV-1 drug resistance mutations (DRMs). Results The amplification/sequencing success rate was 75.2% with 255/339 sequences obtained. Applying a cut-off of 1%, major DRMs to INSTIs were detected in 13 (5.1%) individuals, but only 1 individual harboured an INSTI DRM (E92G) at a nucleotide frequency ≥15%. However, 140/255 (54.9%) individuals harboured polymorphic accessory INSTI DRMs, mainly at high frequencies. In line with that observation, HIV-1 subtype diversity among individuals was high. Conclusions Pretreatment HIV-1 resistance to INSTIs was low in the study sites, which supports the use of INSTIs in Cameroon. Nevertheless, further studies are necessary to assess the impact of polymorphic accessory INSTI DRMs on INSTI-based ART regimens.


2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S390-S390
Author(s):  
Melanie Stecher ◽  
Martin Hoenigl ◽  
Anna-Maria Eis-Huebinger ◽  
Clara Lehmann ◽  
Gerd Fätkenheuer ◽  
...  

Abstract Background Geographical targeting of interventions of hotspots of HIV transmission increases the impact of HIV intervention. We combined molecular epidemiology and geospatial analyses to provide insights into the drivers of HIV transmission and the contribution of geographical hot spots to the rapidly evolving local HIV epidemic of Cologne-Bonn. Methods We included 714 HIV-1-infected ART naïve individuals, followed at the University Hospitals Cologne and Bonn between 2001 and 2016. Phylogenetic and network analyses were performed to infer putative relationships. Assortativity index (AI, i.e., shared attributes) and characteristics of genetically linked individuals were analyzed. The geospatial diffusion of the local epidemic (i.e., viral gene flow) was evaluated using a Slatkin-Maddison approach. Geospatial dispersal of local HIV transmission was determined by calculating the average distance between genetically linked individuals (centroids of 3-digit zip code of residency, ArcGIS®). Results Of 714 sequences, 217 (30.4%) had a putative linkage with at least one other sequence, forming 77 clusters (size range: 2–8). Genetically linked individuals were significantly more likely to live in suburban areas (P = 0.035), &lt;30 years of age (P = 0.013), infected with HIV-1 subtype B (P = 0.002). AI for concurrent area of residency showed that individuals were nonassortative in the network (−0.0026, P = 0.046), indicating that clustering individuals tended to cluster with individuals living in a different zip code. Geospatial analyses revealed that the median distance between genetically linked individuals was 23.4 km, significantly lower than expected (median 39.68 km; P &lt; 0.001) (Figure 1A). Slatkin Maddison analyses revealed increased gene flow originating from Central Cologne toward the surrounding areas (P &lt; 0.001, Figure 1B). Conclusion Phylogeographic analysis suggests that central Cologne may be a significant driver of the regional epidemic. While clustering individuals lived closer than unlinked individuals, they were less likely to be linked to others from their same zip code. This may reflect individuals reaching out of their neighborhoods and social circles to meet new partners. Disclosures All authors: No reported disclosures.


2012 ◽  
Vol 93 (12) ◽  
pp. 2625-2634 ◽  
Author(s):  
Elena Capel ◽  
Glòria Martrus ◽  
Mariona Parera ◽  
Bonaventura Clotet ◽  
Miguel Angel Martínez

The rapid spread of human immunodeficiency virus type 1 (HIV-1) in humans has been accompanied by continuous extensive genetic diversification of the virus. The aim of this study was to investigate the impact of HIV-1 diversification on HIV-1 replication capacity (RC) and mutational robustness. Thirty-three HIV-1 protease sequences were amplified from three groups of viruses: two naïve sample groups isolated 15 years apart plus a third group of protease inhibitor-(PI) resistant samples. The amplified proteases were recombined with an HXB2 infectious clone and RC was determined in MT-4 cells. RC was also measured in these three groups after random mutagenesis in vitro using error-prone PCR. No significant RC differences were observed between recombinant viruses from either early or recent naïve isolates (P = 0.5729), even though the proteases from the recent isolates had significantly lower sequence conservation scores compared with a subtype B ancestral sequence (P<0.0001). Randomly mutated recombinant viruses from the three groups exhibited significantly lower RC values than the corresponding wild-type viruses (P<0.0001). There was no significant difference regarding viral infectivity reduction between viruses carrying randomly mutated naïve proteases from early or recent sample isolates (P = 0.8035). Interestingly, a significantly greater loss of RC was observed in the PI-resistant protease group (P = 0.0400). These results demonstrate that protease sequence diversification has not affected HIV-1 RC or protease robustness and indicate that proteases carrying PI resistance substitutions are less robust than naïve proteases.


2019 ◽  
Vol 63 (8) ◽  
Author(s):  
Kristof Theys ◽  
Pieter J. K. Libin ◽  
Kristel Van Laethem ◽  
Ana B. Abecasis

ABSTRACT Viral pathogens causing global disease burdens are often characterized by high rates of evolutionary changes. The extensive viral diversity at baseline can shorten the time to escape from therapeutic or immune selective pressure and alter mutational pathways. The impact of genotypic background on the barrier to resistance can be difficult to capture, particularly for agents in experimental stages or that are recently approved or expanded into new patient populations. We developed an evolutionary model-based counting method to quickly quantify the population genetic potential to resistance and assess population differences. We demonstrate its applicability to HIV-1 integrase inhibitors, as their increasing use globally contrasts with limited availability of non-B subtype resistant sequence data and corresponding knowledge gap. A large sequence data set encompassing most prevailing HIV-1 subtypes and resistance-associated mutations of currently approved integrase inhibitors was investigated. A complex interplay between codon predominance, polymorphisms, and associated evolutionary costs resulted in a subtype-dependent varied genetic potential for 15 resistance mutations against integrase inhibitors. While we confirm the lower genetic barrier of subtype B for G140S, we convincingly discard a similar effect previously suggested for G140C. A supplementary analysis for HIV-1 reverse transcriptase inhibitors identified a lower genetic barrier for K65R in subtype C through differential codon usage not reported before. To aid evolutionary interpretations of genomic differences for antiviral strategies, we advanced existing counting methods with increased sensitivity to identify subtype dependencies of resistance emergence. Future applications include novel HIV-1 drug classes or vaccines, as well as other viral pathogens.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Chenjie Wan ◽  
◽  
Nadine Bachmann ◽  
Venelin Mitov ◽  
François Blanquart ◽  
...  

Abstract The HIV-1 reservoir is the major hurdle to curing HIV-1. However, the impact of the viral genome on the HIV-1 reservoir, i.e. its heritability, remains unknown. We investigate the heritability of the HIV-1 reservoir size and its long-term decay by analyzing the distribution of those traits on viral phylogenies from both partial-pol and viral near full-length genome sequences. We use a unique nationwide cohort of 610 well-characterized HIV-1 subtype-B infected individuals on suppressive ART for a median of 5.4 years. We find that a moderate but significant fraction of the HIV-1 reservoir size 1.5 years after the initiation of ART is explained by genetic factors. At the same time, we find more tentative evidence for the heritability of the long-term HIV-1 reservoir decay. Our findings indicate that viral genetic factors contribute to the HIV-1 reservoir size and hence the infecting HIV-1 strain may affect individual patients’ hurdle towards a cure.


2005 ◽  
Vol 16 (2) ◽  
pp. 103-115 ◽  
Author(s):  
Hermann Bussmann ◽  
Vladimir Novitsky ◽  
William Wester ◽  
Trevor Peter ◽  
Kereng Masupu ◽  
...  

Current HIV-1 antiretroviral (ARV) drug resistance knowledge is limited to HIV-1 subtype B (HIV-1B). We addressed whether unique genetic and phenotypic properties of HIV-1 subtype C (HIV-1C), southern Africa's most prevalent subtype, may foment earlier and/or distinct resistance mutations. Population-level HIV-1C genotypes were evaluated with respect to drug resistance prevalence before Botswana's public ARV treatment programme began. Viruses were genotyped from 11 representative districts of northern and southern Botswana, and consensus sequences from these 71 individuals and 51 previously reported sequences from HIV-positive blood donors were constructed. Phylogenetic analysis classified all 71 sequences but one, which exhibited pol gene mosaicism, as HIV-1C. The protease and reverse transcriptase coding region had no detectable known primary mutations associated with HIV-1B protease inhibitor (PI) drug resistance. Secondary mutations associated with PI drug resistance were found in all sequences. Several HIV-1C—specific polymorphic sites were found across the pol gene. Northern and southern Botswana viral sequences showed no significant differences from each other. Population genotyping shows that, without countrywide ARV treatment, HIV-1C—infected Batswana harbour virtually no primary mutations known to confer resistance to the three major HIV-1B ARV drug classes. Some secondary PI mutations and polymorphic sites in the protease enzyme necessitate continuous population monitoring, particularly after introduction of countrywide ARV treatment in Botswana. Although its PI resistance development rate and kinetics are not known, our data may suggest increased susceptibility and readiness of HIV-1C to develop resistance under drug pressure when the PI class of drugs is used.


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