Coreceptor Tropism and Maraviroc Sensitivity of Clonally Derived Ethiopian HIV-1C Strains Using an in-house Phenotypic Assay and Commonly Used Genotypic Methods

Objectives:Genotypic Tropism Testing (GTT) tools are generally developed based on HIV-1 subtype B (HIV-1B) and used for HIV-1C as well but with a large discordance of prediction between different methods. We used an established phenotypic assay for comparison with GTT methods and for the determination of in vitro maraviroc sensitivity of pure R5-tropic and dual-tropic HIV-1C.Methods:Plasma was obtained from 58 HIV-1C infected Ethiopians. Envgp120 was cloned into a luciferase tagged NL4-3 plasmid. Phenotypic tropism was determined by in house method and the V3 sequences were analysed by five GTT methods. In vitro maraviroc sensitivity of R5-tropic and dual-tropic isolates were compared in the TZMbl cell-line.Results:The phenotypes were classified as R5 in 92.4% and dual tropic (R5X4) in 7.6% of 79 clones. The concordance between phenotype and genotype ranged from 64.7% to 84.3% depending on the GTT method. Only 46.9% of the R5 phenotypes were predicted as R5 by all GTT tools while R5X4 phenotypes were predicted as X4 by four methods, but not by Raymond’s method. All six tested phenotypic R5 clones, as well as five of six of dual tropic clones, showed a dose response to maraviroc.Conclusion:There is a high discordance between GTT methods, which underestimates the presence of R5 and overestimates X4 strains compared to a phenotypic assay. Currently available GTT algorithms should be further improved for tropism prediction in HIV-1C. Maraviroc has an in vitro activity against most HIV-1C viruses and could be considered as an alternative regimen in individuals infected with CCR5-tropic HIV-1C viruses.

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Mutations in HIV-1gagandpolCompensate for the Loss of Viral Fitness Caused by a Highly Mutated Protease

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00465-12 ◽

2012 ◽

Vol 56 (8) ◽

pp. 4320-4330 ◽

Cited By ~ 30

Author(s):

Milan Kožíšek ◽

Sandra Henke ◽

Klára Grantz Šašková ◽

Graeme Brendon Jacobs ◽

Anita Schuch ◽

...

Keyword(s):

Highly Active Antiretroviral Therapy ◽

Viral Fitness ◽

Drug Pressure ◽

Viral Loads ◽

Highly Active ◽

Subtype B ◽

Hiv 1

ABSTRACTDuring the last few decades, the treatment of HIV-infected patients by highly active antiretroviral therapy, including protease inhibitors (PIs), has become standard. Here, we present results of analysis of a patient-derived, multiresistant HIV-1 CRF02_AG recombinant strain with a highly mutated protease (PR) coding sequence, where up to 19 coding mutations have accumulated in the PR. The results of biochemical analysisin vitroshowed that the patient-derived PR is highly resistant to most of the currently used PIs and that it also exhibits very poor catalytic activity. Determination of the crystal structure revealed prominent changes in the flap elbow region and S1/S1′ active site subsites. While viral loads in the patient were found to be high, the insertion of the patient-derived PR into a HIV-1 subtype B backbone resulted in reduction of infectivity by 3 orders of magnitude. Fitness compensation was not achieved by elevated polymerase (Pol) expression, but the introduction of patient-derivedgagandpolsequences in a CRF02_AG backbone rescued viral infectivity to near wild-type (wt) levels. The mutations that accumulated in the vicinity of the processing sites spanning the p2/NC, NC/p1, and p6pol/PR proteins lead to much more efficient hydrolysis of corresponding peptides by patient-derived PR in comparison to the wt enzyme. This indicates a very efficient coevolution of enzyme and substrate maintaining high viral loadsin vivounder constant drug pressure.

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Use of Coreceptors Other Than CCR5 by Non-Syncytium-Inducing Adult and Pediatric Isolates of Human Immunodeficiency Virus Type 1 Is Rare In Vitro

Journal of Virology ◽

10.1128/jvi.72.11.9337-9344.1998 ◽

1998 ◽

Vol 72 (11) ◽

pp. 9337-9344 ◽

Cited By ~ 106

Author(s):

Yi-jun Zhang ◽

Tatjana Dragic ◽

Yunzhen Cao ◽

Leondios Kostrikis ◽

Douglas S. Kwon ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Viral Entry ◽

Infected Infant ◽

Subtype B ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT We have tested a panel of pediatric and adult human immunodeficiency virus type 1 (HIV-1) primary isolates for the ability to employ the following proteins as coreceptors during viral entry: CCR1, CCR2b, CCR3, CCR4, CCR5, CCR8, CXCR4, Bonzo, BOB, GPR1, V28, US28, and APJ. Most non-syncytium-inducing isolates could utilize only CCR5. All syncytium-inducing viruses used CXCR4, some also employed V28, and one (DH123) used CCR8 and APJ as well. A longitudinal series of HIV-1 subtype B isolates from an infected infant and its mother utilized Bonzo efficiently, as well as CCR5. The maternal isolates, which were syncytium inducing, also used CXCR4, CCR8, V28, and APJ.

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Determination of HIV-1 Chemokine Coreceptor Tropism Using Transduced Human Osteosarcoma (HOS) Cells

HIV Protocols ◽

10.1385/0-89603-369-4:29 ◽

2003 ◽

pp. 29-34

Author(s):

Mark K. Louder ◽

John R. Mascola

Keyword(s):

Coreceptor Tropism ◽

Human Osteosarcoma ◽

Hiv 1

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Synthesis and in vitro activity of novel N-3 acylated TSAO-T compounds against HIV-1 and HCV

European Journal of Medicinal Chemistry ◽

10.1016/j.ejmech.2011.08.017 ◽

2011 ◽

Vol 46 (10) ◽

pp. 5046-5056 ◽

Cited By ~ 7

Author(s):

Marina Moura ◽

Solen Josse ◽

Albert Nguyen Van Nhien ◽

Carole Fournier ◽

Gilles Duverlie ◽

...

Keyword(s):

Vitro Activity ◽

In Vitro Activity ◽

Hiv 1

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Molecular modeling and in vitro activity of an HIV-1-encoded glutathione peroxidase

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.97.12.6356 ◽

2000 ◽

Vol 97 (12) ◽

pp. 6356-6361 ◽

Cited By ~ 58

Author(s):

L. Zhao ◽

A. G. Cox ◽

J. A. Ruzicka ◽

A. A. Bhat ◽

W. Zhang ◽

...

Keyword(s):

Molecular Modeling ◽

Glutathione Peroxidase ◽

Vitro Activity ◽

In Vitro Activity ◽

Hiv 1

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Reanalysis of Coreceptor Tropism in HIV-1-Infected Adults Using a Phenotypic Assay with Enhanced Sensitivity

Clinical Infectious Diseases ◽

10.1093/cid/cir072 ◽

2011 ◽

Vol 52 (7) ◽

pp. 925-928 ◽

Cited By ~ 34

Author(s):

T. J. Wilkin ◽

M. B. Goetz ◽

R. Leduc ◽

G. Skowron ◽

Z. Su ◽

...

Keyword(s):

Coreceptor Tropism ◽

Phenotypic Assay ◽

Enhanced Sensitivity ◽

Hiv 1

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Identification and Characterization of BMS-955176, a Second-Generation HIV-1 Maturation Inhibitor with Improved Potency, Antiviral Spectrum, and Gag Polymorphic Coverage

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02560-15 ◽

2016 ◽

Vol 60 (7) ◽

pp. 3956-3969 ◽

Cited By ~ 37

Author(s):

Beata Nowicka-Sans ◽

Tricia Protack ◽

Zeyu Lin ◽

Zhufang Li ◽

Sharon Zhang ◽

...

Keyword(s):

Human Serum ◽

Second Generation ◽

Mononuclear Cells ◽

Integrase Inhibitor ◽

Wild Type Virus ◽

Peripheral Blood Mononuclear ◽

Subtype B ◽

Maturation Inhibitor ◽

Hiv 1

ABSTRACTBMS-955176 is a second-generation human immunodeficiency virus type 1 (HIV-1) maturation inhibitor (MI). A first-generation MI, bevirimat, showed clinical efficacy in early-phase studies, but ∼50% of subjects had viruses with reduced susceptibility associated with naturally occurring polymorphisms in Gag near the site of MI action. MI potency was optimized using a panel of engineered reporter viruses containing site-directed polymorphic changes in Gag that reduce susceptibility to bevirimat (including V362I, V370A/M/Δ, and T371A/Δ), leading incrementally to the identification of BMS-955176. BMS-955176 exhibits potent activity (50% effective concentration [EC50], 3.9 ± 3.4 nM [mean ± standard deviation]) toward a library (n= 87) ofgag/prrecombinant viruses representing 96.5% of subtype B polymorphic Gag diversity near the CA/SP1 cleavage site. BMS-955176 exhibited a median EC50of 21 nM toward a library of subtype B clinical isolates assayed in peripheral blood mononuclear cells (PBMCs). Potent activity was maintained against a panel of reverse transcriptase, protease, and integrase inhibitor-resistant viruses, with EC50s similar to those for the wild-type virus. A 5.4-fold reduction in EC50occurred in the presence of 40% human serum plus 27 mg/ml of human serum albumin (HSA), which corresponded well to anin vitromeasurement of 86% human serum binding. Time-of-addition and pseudotype reporter virus studies confirm a mechanism of action for the compound that occurs late in the virus replication cycle. BMS-955176 inhibits HIV-1 protease cleavage at the CA/SP1 junction within Gag in virus-like particles (VLPs) and in HIV-1-infected cells, and it binds reversibly and with high affinity to assembled Gag in purified HIV-1 VLPs. Finally,in vitrocombination studies showed no antagonistic interactions with representative antiretrovirals (ARVs) of other mechanistic classes. In conclusion, BMS-955176 is a second-generation MI with potentin vitroanti-HIV-1 activity and a greatly improved preclinical profile compared to that of bevirimat.

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Screening Test Method for the Determination of the in vitro Activity of Topical Antimycotics

Mycoses ◽

10.1111/j.1439-0507.1984.tb02041.x ◽

2009 ◽

Vol 27 (7) ◽

pp. 348-354 ◽

Cited By ~ 3

Author(s):

L. Gip ◽

Ch. Gip

Keyword(s):

Screening Test ◽

Test Method ◽

Vitro Activity ◽

In Vitro Activity

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Influence of several drugs on the in vivo and in vitro activity of mammalian hepatic azo-reductase

Canadian Journal of Biochemistry ◽

10.1139/o68-054 ◽

1968 ◽

Vol 46 (4) ◽

pp. 367-371 ◽

Cited By ~ 4

Author(s):

John V. Burba

Keyword(s):

Guinea Pigs ◽

Marked Decrease ◽

Reductase Activity ◽

Sulfanilic Acid ◽

In Vitro Activity ◽

Appreciable Increase ◽

Azo Reductase

The ability of a variety of drugs to influence liver azo-reductase activity of rabbits, rats, and guinea pigs in vitro was determined. Only nitrofurantoin showed a marked stimulatory activity in the three species. There was no appreciable inhibitory activity with any of the drugs tested. Determination of azo-reductase activity in vivo after pretreatment of the animals with phenobarbital and nitrofurantoin showed that there was an appreciable increase only in the azo-reductase activity of rats with phenobarbital, and only rabbits showed a marked decrease in azo-reductase activity with nitrofurantoin. Under the same conditions there was an appreciable increase in the excretion of N-acetylated sulfanilic acid by phenobarbital-pretreated rats and guinea pigs, while with nitrofurantoin rabbits showed an increase and rats a large decrease in the excretion of N-acetylated sulfanilic acid.

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