scholarly journals Variant Human Immunodeficiency Virus Type 1 Proteases and Response to Combination Therapy Including a Protease Inhibitor

2001 ◽  
Vol 45 (3) ◽  
pp. 893-900 ◽  
Author(s):  
Jean Servais ◽  
Christine Lambert ◽  
Elodie Fontaine ◽  
Jean-Marc Plesséria ◽  
Isabelle Robert ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Protease Inhibitor ◽  
Drug Regimen ◽  
Reference Sequence ◽  
Wild Type Virus ◽  
Protease Gene ◽  
Clade B ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The objective of this observational study was to assess the genetic variability in the human immunodeficiency virus (HIV) protease gene from HIV type 1 (HIV-1)-positive (clade B), protease inhibitor-naı̈ve patients and to evaluate its association with the subsequent effectiveness of a protease inhibitor-containing triple-drug regimen. The protease gene was sequenced from plasma-derived virus from 116 protease inhibitor-naı̈ve patients. The virological response to a triple-drug regimen containing indinavir, ritonavir, or saquinavir was evaluated every 3 months for as long as 2 years (n = 40). A total of 36 different amino acid substitutions compared to the reference sequence (HIV-1 HXB2) were detected. No substitutions at the active site similar to the primary resistance mutations were found. The most frequent substitutions (prevalence, >10%) at baseline were located at codons 15, 13, 12, 62, 36, 64, 41, 35, 3, 93, 77, 63, and 37 (in ascending order of frequency). The mean number of polymorphisms was 4.2. A relatively poorer response to therapy was associated with a high number of baseline polymorphisms and, to a lesser extent, with the presence of I93L at baseline in comparison with the wild-type virus. A71V/T was slightly associated with a poorer response to first-line ritonavir-based therapy. In summary, within clade B viruses, protease gene natural polymorphisms are common. There is evidence suggesting that treatment response is associated with this genetic background, but most of the specific contributors could not be firmly identified. I93L, occurring in about 30% of untreated patients, may play a role, as A71V/T possibly does in ritonavir-treated patients.

scholarly journals An Envelope Modification That Renders a Primary, Neutralization-Resistant Clade B Human Immunodeficiency Virus Type 1 Isolate Highly Susceptible to Neutralization by Sera from Other Clades

1998 ◽  
Vol 72 (10) ◽  
pp. 7840-7845 ◽  
Author(s):  
Leonidas Stamatatos ◽  
Cecilia Cheng-Mayer
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Mononuclear Cells ◽  
Mutant Virus ◽  
Wild Type Virus ◽  
Clade B ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT SF162 is a primary (PR), non-syncytium-inducing, macrophagetropic human immunodeficiency virus type 1 (HIV-1) clade B isolate which is resistant to antibody-mediated neutralization. Deletion of the first or second hypervariable envelope gp120 region (V1 or V2 loop, respectively) of this virus does not abrogate its ability to replicate in peripheral blood mononuclear cells and primary macrophages, nor does it alter its coreceptor usage profile. The mutant virus with the V1 loop deletion, SF162ΔV1, remains as resistant to antibody-mediated neutralization as the wild-type virus SF162. In contrast, the mutant virus with the V2 loop deletion, SF162ΔV2, exhibits enhanced susceptibility to neutralization by certain monoclonal antibodies whose epitopes are located within the CD4-binding site and conserved regions of gp120. More importantly, SF162ΔV2 is now up to 170-fold more susceptible to neutralization than SF162 by sera collected from patients infected with clade B HIV-1 isolates. In addition, it becomes susceptible to neutralization by sera collected from patients infected with clade A, C, D, E, and F HIV-1 isolates. These findings suggest that the V2, but not the V1, loop of SF162 shields an as yet unidentified region of the HIV envelope rich in neutralization epitopes and that the overall structure of this region appears to be conserved among clade B, C, D, E, and F HIV-1 PR isolates.

scholarly journals Polymorphism of the Human Immunodeficiency Virus Type 1 (HIV-1) Protease Gene and Response of HIV-1-Infected Patients to a Protease Inhibitor

1999 ◽  
Vol 37 (9) ◽  
pp. 2910-2912 ◽  
Author(s):  
Philippe Bossi ◽  
Mireille Mouroux ◽  
Anne Yvon ◽  
François Bricaire ◽  
Henri Agut ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Protease Inhibitor ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Protease Gene ◽  
Subtype B ◽  
Immunodeficiency Virus ◽  
The Impact ◽  
Hiv 1

In order to analyze the impact of protease gene polymorphism on response to regimens containing a protease inhibitor, the entire protease coding domain from 58 human immunodeficiency virus type 1 (HIV-1)-infected patients who were protease inhibitor naive was sequenced before therapy was started. Plasma HIV-1 RNA levels were measured at baseline and at month 3 and month 6 after treatment. All patients were treated with a combination of two reverse transcriptase inhibitors and a protease inhibitor (saquinavir EOF [n = 28], ritonavir [n = 16], or indinavir [n = 14]). Before treatment, 30 different positions whose codons differed from the subtype B consensus sequence were observed. Major mutations associated with protease inhibitor resistance were not observed. No statistical correlation between the number of amino acid differences and the treatment efficacy at month 3 (−2.4 log) or month 6 (−2.7 log) was observed. At baseline, genotypic analysis of the HIV-1 protease gene of patients who have never received a protease inhibitor does not allow prediction of the efficacy of regimens containing a protease inhibitor.

scholarly journals In Vitro Selection and Characterization of Human Immunodeficiency Virus Type 1 Variants with Increased Resistance to ABT-378, a Novel Protease Inhibitor

1998 ◽  
Vol 72 (9) ◽  
pp. 7532-7541 ◽  
Author(s):  
Alejandro Carrillo ◽  
Kent D. Stewart ◽  
Hing L. Sham ◽  
Daniel W. Norbeck ◽  
William E. Kohlbrenner ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Protease Inhibitor ◽  
Selection Process ◽  
Protease Gene ◽  
Wild Type ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
Type Sequence

ABSTRACT ABT-378, a new human immunodeficiency virus type 1 (HIV-1) protease inhibitor which is significantly more active than ritonavir in cell culture, is currently under investigation for the treatment of AIDS. Development of viral resistance to ABT-378 in vitro was studied by serial passage of HIV-1 (pNL4-3) in MT-4 cells. Selection of viral variants with increasing concentrations of ABT-378 revealed a sequential appearance of mutations in the protease gene: I84V-L10F-M46I-T91S-V32I-I47V. Further selection at a 3.0 μM inhibitor concentration resulted in an additional change at residue 47 (V47A), as well as reversion at residue 32 back to the wild-type sequence. The 50% effective concentration of ABT-378 against passaged virus containing these additional changes was 338-fold higher than that against wild-type virus. In addition to changes in the protease gene, sequence analysis of passaged virus revealed mutations in the p1/p6 (P1′ residue Leu to Phe) and p7/p1 (P2 residue Ala to Val) gag proteolytic processing sites. The p1/p6 mutation appeared in several clones derived from early passages and was present in all clones obtained from passage P11 (0.42 μM ABT-378) onward. The p7/p1 mutation appeared very late during the selection process and was strongly associated with the emergence of the additional change at residue 47 (V47A) and the reversion at residue 32 back to the wild-type sequence. Furthermore, this p7/p1 mutation was present in all clones obtained from passage P17 (3.0 μM ABT-378) onward and always occurred in conjunction with the p1/p6 mutation. Full-length molecular clones containing protease mutations observed very late during the selection process were constructed and found to be viable only in the presence of both the p7/p1 and p1/p6 cleavage-site mutations. This suggests that mutation of these gagproteolytic cleavage sites is required for the growth of highly resistant HIV-1 selected by ABT-378 and supports recent work demonstrating that mutations in the p7/p1/p6 region play an important role in conferring resistance to protease inhibitors (L. Doyon et al., J. Virol. 70:3763–3769, 1996; Y. M. Zhang et al., J. Virol. 71:6662–6670, 1997).

scholarly journals Novel bis-Tetrahydrofuranylurethane-Containing Nonpeptidic Protease Inhibitor (PI) UIC-94017 (TMC114) with Potent Activity against Multi-PI-Resistant Human Immunodeficiency Virus In Vitro

2003 ◽  
Vol 47 (10) ◽  
pp. 3123-3129 ◽  
Author(s):  
Yasuhiro Koh ◽  
Hirotomo Nakata ◽  
Kenji Maeda ◽  
Hiromi Ogata ◽  
Geoffrey Bilcer ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Protease Inhibitor ◽  
Therapeutic Agent ◽  
Close Contact ◽  
Wide Spectrum ◽  
Antiviral Agents ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT We designed, synthesized, and identified UIC-94017 (TMC114), a novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI) containing a 3(R),3a(S),6a(R)-bis-tetrahydrofuranylurethane (bis-THF) and a sulfonamide isostere which is extremely potent against laboratory HIV-1 strains and primary clinical isolates (50% inhibitory concentration [IC50], ∼0.003 μM; IC90, ∼0.009 μM) with minimal cytotoxicity (50% cytotoxic concentration for CD4+ MT-2 cells, 74 μM). UIC-94017 blocked the infectivity and replication of each of HIV-1NL4-3 variants exposed to and selected for resistance to saquinavir, indinavir, nelfinavir, or ritonavir at concentrations up to 5 μM (IC50s, 0.003 to 0.029 μM), although it was less active against HIV-1NL4-3 variants selected for resistance to amprenavir (IC50, 0.22 μM). UIC-94017 was also potent against multi-PI-resistant clinical HIV-1 variants isolated from patients who had no response to existing antiviral regimens after having received a variety of antiviral agents. Structural analyses revealed that the close contact of UIC-94017 with the main chains of the protease active-site amino acids (Asp-29 and Asp-30) is important for its potency and wide spectrum of activity against multi-PI-resistant HIV-1 variants. Considering the favorable pharmacokinetics of UIC-94017 when administered with ritonavir, the present data warrant that UIC-94017 be further developed as a potential therapeutic agent for the treatment of primary and multi-PI-resistant HIV-1 infections.

scholarly journals The Thiocarboxanilide Nonnucleoside Inhibitor UC781 Restores Antiviral Activity of 3′-Azido-3′-Deoxythymidine (AZT) against AZT-Resistant Human Immunodeficiency Virus Type 1

1999 ◽  
Vol 43 (2) ◽  
pp. 259-263 ◽  
Author(s):  
Gadi Borkow ◽  
Dominique Arion ◽  
Mark A. Wainberg ◽  
Michael A. Parniak
Keyword(s):  
Human Immunodeficiency Virus ◽  
Antiviral Activity ◽  
Reverse Transcriptase ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Wild Type Virus ◽  
Wild Type ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT N-[4-Chloro-3-(3-methyl-2-butenyloxy)phenyl]-2-methyl-3-furancarbothioamide (UC781) is an exceptionally potent nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. We found that a 1:1 molar combination of UC781 and 3′-azido-3′-deoxythymidine (AZT) showed high-level synergy in inhibiting the replication of AZT-resistant virus, implying that UC781 can restore antiviral activity to AZT against AZT-resistant HIV-1. Neither the nevirapine plus AZT nor the 2′,5′-bis-O-(t-butyldimethylsilyl)-3′-spiro-5"-(4"-amino-1",2"-oxathiole-2",2"-dioxide plus AZT combinations had this effect. Studies with purified HIV-1 reverse transcriptase (from a wild type and an AZT-resistant mutant) showed that UC781 was a potent inhibitor of the pyrophosphorolytic cleavage of nucleotides from the 3′ end of the DNA polymerization primer, a process that we have proposed to be critical for the phenotypic expression of AZT resistance. Combinations of UC781 plus AZT did not act in synergy to inhibit the replication of either wild-type virus or UC781-resistant HIV-1. Importantly, the time to the development of viral resistance to combinations of UC781 plus AZT is significantly delayed compared to the time to the development of resistance to either drug alone.

scholarly journals Multiple human immunodeficiency virus type 1 Nef functions contribute to efficient replication in primary human macrophages

2004 ◽  
Vol 85 (6) ◽  
pp. 1463-1469 ◽  
Author(s):  
Amanda Brown ◽  
Shaghayegh Moghaddam ◽  
Thomas Kawano ◽  
Cecilia Cheng-Mayer
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Single Point ◽  
Wild Type Virus ◽  
Wild Type ◽  
Immunodeficiency Virus ◽  
Efficient Replication ◽  
Hiv 1

The human immunodeficiency virus type 1 (HIV-1) Nef protein has been shown to accelerate viral growth kinetics in primary human T-lymphocytes and macrophages; however, the specific function(s) of Nef responsible for this phenotype in macrophages is unknown. To address this issue, mutants of a molecularly cloned macrophage-tropic isolate, HIV-1SF162, were generated expressing single point mutations that abrogate the ability of Nef to interact with cellular kinases or mediate CD4 down-regulation. Infection of primary monocyte-derived macrophages (MDM) with these mutant viruses revealed that residues in the PXXP motif contribute to efficient replication. Interestingly, viruses expressing alleles of Nef defective in CD4 down-modulation activity retain wild-type levels of infectivity in single-round assays but exhibited delayed replication kinetics and grew to lower titres compared to the wild-type virus in MDM. These data suggest that efficient HIV-1 replication is dependent on the ability of Nef to interact with cellular kinases and remove CD4 from the surface of infected macrophages.

scholarly journals Viral Phenotypes and Antibody Responses in Long-Term Survivors Infected with Attenuated Human Immunodeficiency Virus Type 1 Containing Deletions in the nef and Long Terminal Repeat Regions

2007 ◽  
Vol 81 (17) ◽  
pp. 9268-9278 ◽  
Author(s):  
Erin E. Verity ◽  
Dimitra Zotos ◽  
Kim Wilson ◽  
Catherine Chatfield ◽  
Victoria A. Lawson ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Wild Type Virus ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The Sydney Blood Bank Cohort (SBBC) consists of eight blood transfusion recipients infected with nef-attenuated human immunodeficiency virus type 1 (HIV-1) acquired from a single donor. Here, we show that viral phenotypes and antibody responses differ considerably between individual cohort members, despite the single source of infection. Replication of isolated virus varied from barely detectable to similar to that of the wild-type virus, and virus isolated from five SBBC members showed coreceptor usage signatures unique to each individual. Higher viral loads and stronger neutralizing antibody responses were associated with better-replicating viral strains, and detectable viral replication was essential for the development of strong and sustained humoral immune responses. Despite the presence of strong neutralizing antibodies in a number of SBBC members, disease progression was not prevented, and each cohort member studied displayed a unique outcome of infection with nef-attenuated HIV-1.

scholarly journals TMC310911, a Novel Human Immunodeficiency Virus Type 1 Protease Inhibitor, ShowsIn Vitroan Improved Resistance Profile and Higher Genetic Barrier to Resistance Compared with Current Protease Inhibitors

2011 ◽  
Vol 55 (12) ◽  
pp. 5723-5731 ◽  
Author(s):  
Inge Dierynck ◽  
Herwig Van Marck ◽  
Marcia Van Ginderen ◽  
Tim H. M. Jonckers ◽  
Madhavi N. L. Nalam ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Protease Inhibitor ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Clinical Isolates ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
Selection Of

ABSTRACTTMC310911 is a novel human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI) structurally closely related to darunavir (DRV) but with improved virological characteristics. TMC310911 has potent activity against wild-type (WT) HIV-1 (median 50% effective concentration [EC50], 14 nM) and a wide spectrum of recombinant HIV-1 clinical isolates, including multiple-PI-resistant strains with decreased susceptibility to currently approved PIs (fold change [FC] in EC50, >10). For a panel of 2,011 recombinant clinical isolates with decreased susceptibility to at least one of the currently approved PIs, the FC in TMC310911 EC50was ≤4 for 82% of isolates and ≤10 for 96% of isolates. The FC in TMC310911 EC50was ≤4 and ≤10 for 72% and 94% of isolates with decreased susceptibility to DRV, respectively.In vitroresistance selection (IVRS) experiments with WT virus and TMC310911 selected for mutations R41G or R41E, but selection of resistant virus required a longer time than IVRS performed with WT virus and DRV. IVRS performed with r13025, a multiple-PI-resistant recombinant clinical isolate, and TMC310911 selected for mutations L10F, I47V, and L90M (FC in TMC310911 EC50= 16). IVRS performed with r13025 in the presence of DRV required less time and resulted in more PI resistance-associated mutations (V32I, I50V, G73S, L76V, and V82I; FC in DRV EC50= 258). The activity against a comprehensive panel of PI-resistant mutants and the limitedin vitroselection of resistant viruses under drug pressure suggest that TMC310911 represents a potential drug candidate for the management of HIV-1 infection for a broad range of patients, including those with multiple PI resistance.

scholarly journals In Vitro Antiviral Activity of the Novel, Tyrosyl-Based Human Immunodeficiency Virus (HIV) Type 1 Protease Inhibitor Brecanavir (GW640385) in Combination with Other Antiretrovirals and against a Panel of Protease Inhibitor-Resistant HIV

2007 ◽  
Vol 51 (9) ◽  
pp. 3147-3154 ◽  
Author(s):  
Richard Hazen ◽  
Robert Harvey ◽  
Robert Ferris ◽  
Charles Craig ◽  
Phillip Yates ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Antiviral Activity ◽  
Protease Inhibitor ◽  
Reverse Transcriptase ◽  
In Vitro Assays ◽  
Immunodeficiency Virus ◽  
Anti Hiv ◽  
Hiv 1

ABSTRACT Brecanavir, a novel tyrosyl-based arylsulfonamide, high-affinity, human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI), has been evaluated for anti-HIV activity in several in vitro assays. Preclinical assessment of brecanavir indicated that this compound potently inhibited HIV-1 in cell culture assays with 50% effective concentrations (EC50s) of 0.2 to 0.53 nM and was equally active against HIV strains utilizing either the CXCR4 or CCR5 coreceptor, as was found with other PIs. The presence of up to 40% human serum decreased the anti-HIV-1 activity of brecanavir by 5.2-fold, but under these conditions the compound retained single-digit nanomolar EC50s. When brecanavir was tested in combination with nucleoside reverse transcriptase inhibitors, the antiviral activity of brecanavir was synergistic with the effects of stavudine and additive to the effects of zidovudine, tenofovir, dideoxycytidine, didanosine, adefovir, abacavir, lamivudine, and emtricitabine. Brecanavir was synergistic with the nonnucleoside reverse transcriptase inhibitor nevirapine or delavirdine and was additive to the effects of efavirenz. In combination with other PIs, brecanavir was additive to the activities of indinavir, lopinavir, nelfinavir, ritonavir, amprenavir, saquinavir, and atazanavir. Clinical HIV isolates from PI-experienced patients were evaluated for sensitivity to brecanavir and other PIs in a recombinant virus assay. Brecanavir had a <5-fold increase in EC50s against 80% of patient isolates tested and had a greater mean in vitro potency than amprenavir, indinavir, lopinavir, atazanavir, tipranavir, and darunavir. Brecanavir is by a substantial margin the most potent and broadly active antiviral agent among the PIs tested in vitro.

scholarly journals Effects of Tat proteins and Tat mutants of different human immunodeficiency virus type 1 clades on glial JC virus early and late gene transcription

2013 ◽  
Vol 94 (3) ◽  
pp. 514-523 ◽  
Author(s):  
Clayton A. Wright ◽  
Jonas A. Nance ◽  
Edward M. Johnson
Keyword(s):  
Human Immunodeficiency Virus ◽  
Dna Replication ◽  
Gene Transcription ◽  
Cellular Proteins ◽  
Late Gene ◽  
Clade B ◽  
Immunodeficiency Virus ◽  
The Brain ◽  
Hiv 1

Polyomavirus JC (JCV) is the aetiological agent of progressive multifocal leukoencephalopathy (PML), a frequently fatal infection of the brain afflicting nearly 4 % of AIDS patients in the USA. Human immunodeficiency virus type 1 (HIV-1) Tat, acting together with cellular proteins at the JCV non-coding control region (NCCR), can stimulate JCV DNA transcription and replication. Tat in the brain is secreted by HIV-1-infected cells and incorporated by oligodendroglia, cells capable of infection by JCV. Thus far the effects of Tat on JCV have been studied primarily with protein encoded by the HIV-1 B clade most common in North America. Here, we determine the abilities of Tat from different HIV-1 clades to alter JCV early and late gene transcription and DNA replication initiated at the JCV origin. Tat from all clades tested stimulates both JCV early and late gene promoters, with clade B Tat being significantly most effective. Tat proteins from the HIV-1 clades display parallel patterns of differences in their effects on HIV-1 and JCV transcription, suggesting that Tat effects in both cases are mediated by the same cellular proteins. Clade B Tat is most effective at directing Smad mediators of tumour growth factor beta and cellular partner Purα to the NCCR. Tat proteins from all non-B clades inhibit initiation of JCV DNA replication. The effectiveness of HIV-1 clade B Tat at promoting JCV transcriptional and replicative processes highlights a need for further investigation to determine which molecular aspects of Tat from distinct HIV-1 substrains can contribute to the course of PML development in neuroAIDS.

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