Characterization of an in vitro-selected RNA ligand to the HIV-1 rev protein

ABSTRACT A novel fibronectin-based protein (Adnectin) HIV-1 inhibitor was generated using in vitro selection. This inhibitor binds to human CD4 with a high affinity (3.9 nM) and inhibits viral entry at a step after CD4 engagement and preceding membrane fusion. The progenitor sequence of this novel inhibitor was selected from a library of trillions of Adnectin variants using mRNA display and then further optimized for improved antiviral and physical properties. The final optimized inhibitor exhibited full potency against a panel of 124 envelope (gp160) proteins spanning 11 subtypes, indicating broad-spectrum activity. Resistance profiling studies showed that this inhibitor required 30 passages (151 days) in culture to acquire sufficient resistance to result in viral titer breakthrough. Resistance mapped to the loss of multiple potential N-linked glycosylation sites in gp120, suggesting that inhibition is due to steric hindrance of CD4-binding-induced conformational changes.

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In Vitro Evolution of Functional Nucleic Acids: High-Affinity RNA Ligands of the HIV-1 rev Protein

The Polymerase Chain Reaction ◽

10.1007/978-1-4612-0257-8_20 ◽

1994 ◽

pp. 233-243 ◽

Cited By ~ 1

Author(s):

Craig Tuerk ◽

Sheela MacDougal-Waugh ◽

Gerald Z. Hertz ◽

Larry Gold

Keyword(s):

Nucleic Acids ◽

In Vitro Evolution ◽

High Affinity ◽

Rna Ligands ◽

Functional Nucleic Acids ◽

Hiv 1 ◽

Rev Protein

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Biochemical characterization of HIV-1 Rev as a potent activator of casein kinase II in vitro

FEBS Letters ◽

10.1016/s0014-5793(98)00538-9 ◽

1998 ◽

Vol 428 (3) ◽

pp. 235-240 ◽

Cited By ~ 26

Author(s):

Kenzo Ohtsuki ◽

Toshiro Maekawa ◽

Shigeyoshi Harada ◽

Atsushi Karino ◽

Yuko Morikawa ◽

...

Keyword(s):

Biochemical Characterization ◽

Casein Kinase Ii ◽

Casein Kinase ◽

Hiv 1

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Characterization of a Mutant HIV-1 Reverse Transcriptase Resistant to (+)-(5S)-4,5,6,7-tetrahydro-5-methyl-6-(3-methyl-2-butenyl)-imidazo[4,5,1-jk][1,4]benzodiazepin-2(1H)-thione (TIBO R82150)

Antiviral Chemistry and Chemotherapy ◽

10.1177/095632029400500410 ◽

1994 ◽

Vol 5 (4) ◽

pp. 278-281

Author(s):

H. Samanta ◽

R. Rose ◽

A. K. Patick ◽

C. M. Bechtold ◽

J. Trimble ◽

...

Keyword(s):

Reverse Transcriptase ◽

Nucleoside Reverse Transcriptase Inhibitor ◽

Serial Passage ◽

Transcriptase Inhibitor ◽

Viral Resistance ◽

Resistant Virus ◽

Reverse Transcriptase Inhibitor ◽

Hiv 1

A virus strain resistant to R82150, a non-nucleoside reverse transcriptase (NNRT) inhibitor (tetrahydro-imidazo [4,5, 1- jk] [1,4] benzodiazepine-2(1 H)-thione), was isolated following serial passage of HIV-1 RF in CEM-SS cells. The virus is cross-resistant to another non-nucleoside reverse transcriptase inhibitor, TGG-II-23A [1,4-dimethyl-1-[5,5-dimethyl-2-oxazoionyl]-naphthalen-2-one), but remains susceptible to AZT, DDI, D4T and phosphonoformate (PFA). DNA sequencing of reverse transcriptase genes from resistant virus indicated that R82150 selects for amino acid alterations Y181C and V108I. In vitro mutagenized reverse transcriptase and recombinant HIV-1 (pNL4-3) carrying either of the mutations have been generated. Genotypic and phenotypic analyses identified V108I as an unreported R82150-associated mutation. Both reverse transcriptase and viral resistance assays indicated that the resistance conferred by the V108I mutation is 7-fold less than that conferred by Y181C.

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Novel Acylguanidine-Based Inhibitor of HIV-1

Journal of Virology ◽

10.1128/jvi.01107-16 ◽

2016 ◽

Vol 90 (20) ◽

pp. 9495-9508 ◽

Cited By ~ 9

Author(s):

Philip Mwimanzi ◽

Ian Tietjen ◽

Scott C. Miller ◽

Aniqa Shahid ◽

Kyle Cobarrubias ◽

...

Keyword(s):

Protein Interactions ◽

Antiretroviral Drugs ◽

Virion Release ◽

Viral Egress ◽

Pharmacological Studies ◽

Infected Cells ◽

New Treatments ◽

Hiv 1

ABSTRACTThe emergence of transmissible HIV-1 strains with resistance to antiretroviral drugs highlights a continual need for new therapies. Here we describe a novel acylguanidine-containing compound, 1-(2-(azepan-1-yl)nicotinoyl)guanidine (or SM111), that inhibitsin vitroreplication of HIV-1, including strains resistant to licensed protease, reverse transcriptase, and integrase inhibitors, without major cellular toxicity. At inhibitory concentrations, intracellular p24Gagproduction was unaffected, but virion release (measured as extracellular p24Gag) was reduced and virion infectivity was substantially impaired, suggesting that SM111 acts at a late stage of viral replication. SM111-mediated inhibition of HIV-1 was partially overcome by a Vpu I17R mutation alone or a Vpu W22* truncation in combination with Env N136Y. These mutations enhanced virion infectivity and Env expression on the surface of infected cells in the absence and presence of SM111 but also impaired Vpu's ability to downregulate CD4 and BST2/tetherin. Taken together, our results support acylguanidines as a class of HIV-1 inhibitors with a distinct mechanism of action compared to that of licensed antiretrovirals. Further research on SM111 and similar compounds may help to elucidate knowledge gaps related to Vpu's role in promoting viral egress and infectivity.IMPORTANCENew inhibitors of HIV-1 replication may be useful as therapeutics to counteract drug resistance and as reagents to perform more detailed studies of viral pathogenesis. SM111 is a small molecule that blocks the replication of wild-type and drug-resistant HIV-1 strains by impairing viral release and substantially reducing virion infectivity, most likely through its ability to prevent Env expression at the infected cell surface. Partial resistance to SM111 is mediated by mutations in Vpu and/or Env, suggesting that the compound affects host/viral protein interactions that are important during viral egress. Further characterization of SM111 and similar compounds may allow more detailed pharmacological studies of HIV-1 egress and provide opportunities to develop new treatments for HIV-1.

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Characterization of the defective interaction between a subset of natural killer cells and dendritic cells in HIV-1 infection

Journal of Experimental Medicine ◽

10.1084/jem.20060894 ◽

2006 ◽

Vol 203 (10) ◽

pp. 2339-2350 ◽

Cited By ~ 129

Author(s):

Domenico Mavilio ◽

Gabriella Lombardo ◽

Audrey Kinter ◽

Manuela Fogli ◽

Andrea La Sala ◽

...

Keyword(s):

Dendritic Cells ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Cell Subset ◽

Interferon Γ ◽

And Function ◽

Hiv 1

In this study, we demonstrate that the in vitro interactions between a CD56neg/CD16pos (CD56neg) subset of natural killer (NK) cells and autologous dendritic cells (DCs) from HIV-1–infected viremic but not aviremic individuals are markedly impaired and likely interfere with the development of an effective immune response. Among the defective interactions are abnormalities in the process of reciprocal NK–DC activation and maturation as well as a defect in the NK cell–mediated editing or elimination of immature DCs (iDCs). Notably, the lysis of mature DCs (mDCs) by autologous NK cells was highly impaired even after the complete masking of major histocompatibility complex I molecules, suggesting that the defective elimination of autologous iDCs is at the level of activating NK cell receptors. In this regard, the markedly impaired expression/secretion and function of NKp30 and TNF-related apoptosis-inducing ligand, particularly among the CD56neg NK cell subset, largely accounts for the highly defective NK cell–mediated lysis of autologous iDCs. Moreover, mDCs generated from HIV-1 viremic but not aviremic patients are substantially impaired in their ability to secrete interleukin (IL)-10 and -12 and to prime the proliferation of neighboring autologous NK cells, which, in turn, fail to secrete adequate amounts of interferon-γ.

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Enhancing and shaping the immunogenicity of native-like HIV-1 envelope trimers with a two-component protein nanoparticle

Nature Communications ◽

10.1038/s41467-019-12080-1 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 35

Author(s):

Philip J. M. Brouwer ◽

Aleksandar Antanasijevic ◽

Zachary Berndsen ◽

Anila Yasmeen ◽

Brooke Fiala ◽

...

Keyword(s):

Animal Models ◽

High Efficiency ◽

Neutralizing Antibody ◽

Two Component ◽

Nanoparticle System ◽

Hiv 1 ◽

Component Protein

Abstract The development of native-like HIV-1 envelope (Env) trimer antigens has enabled the induction of neutralizing antibody (NAb) responses against neutralization-resistant HIV-1 strains in animal models. However, NAb responses are relatively weak and narrow in specificity. Displaying antigens in a multivalent fashion on nanoparticles (NPs) is an established strategy to increase their immunogenicity. Here we present the design and characterization of two-component protein NPs displaying 20 stabilized SOSIP trimers from various HIV-1 strains. The two-component nature permits the incorporation of exclusively well-folded, native-like Env trimers into NPs that self-assemble in vitro with high efficiency. Immunization studies show that the NPs are particularly efficacious as priming immunogens, improve the quality of the Ab response over a conventional one-component nanoparticle system, and are most effective when SOSIP trimers with an apex-proximate neutralizing epitope are displayed. Their ability to enhance and shape the immunogenicity of SOSIP trimers make these NPs a promising immunogen platform.

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