scholarly journals Comparison of the antiviral activity of the microbicide candidate griffithsin and its tandemers derivatives against different modes of HIV-1 transmission

Virology ◽  
2020 ◽  
Vol 544 ◽  
pp. 12-20 ◽  
Author(s):  
Kabamba Alexandre ◽  
Kanyane Malatji ◽  
Takalani Mulaudzi
Keyword(s):  
Antiviral Activity ◽  
Hiv 1 ◽  
Microbicide Candidate

scholarly journals SUMOylation of SAMHD1 at Lysine 595 is required for HIV-1 restriction in non-cycling cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Charlotte Martinat ◽  
Arthur Cormier ◽  
Joëlle Tobaly-Tapiero ◽  
Noé Palmic ◽  
Nicoletta Casartelli ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Reverse Transcription ◽  
Immune Cells ◽  
Viral Restriction ◽  
Antiviral Function ◽  
Hiv 1 ◽  
Constitutively Active

AbstractSAMHD1 is a cellular triphosphohydrolase (dNTPase) proposed to inhibit HIV-1 reverse transcription in non-cycling immune cells by limiting the supply of the dNTP substrates. Yet, phosphorylation of T592 downregulates SAMHD1 antiviral activity, but not its dNTPase function, implying that additional mechanisms contribute to viral restriction. Here, we show that SAMHD1 is SUMOylated on residue K595, a modification that relies on the presence of a proximal SUMO-interacting motif (SIM). Loss of K595 SUMOylation suppresses the restriction activity of SAMHD1, even in the context of the constitutively active phospho-ablative T592A mutant but has no impact on dNTP depletion. Conversely, the artificial fusion of SUMO2 to a non-SUMOylatable inactive SAMHD1 variant restores its antiviral function, a phenotype that is reversed by the phosphomimetic T592E mutation. Collectively, our observations clearly establish that lack of T592 phosphorylation cannot fully account for the restriction activity of SAMHD1. We find that SUMOylation of K595 is required to stimulate a dNTPase-independent antiviral activity in non-cycling immune cells, an effect that is antagonized by cyclin/CDK-dependent phosphorylation of T592 in cycling cells.

scholarly journals Design, Synthesis, and antiviral activity of a series of CD4-mimetic small-molecule HIV-1 entry inhibitors

2021 ◽  
pp. 116000
Author(s):  
Francesca Curreli ◽  
Shahad Ahmed ◽  
Sofia M. Benedict Victor ◽  
Ildar R. Iusupov ◽  
Evgeny A. Spiridonov ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Small Molecule ◽  
Design Synthesis ◽  
Entry Inhibitors ◽  
Hiv 1

scholarly journals Flavonol 7-O-Glucoside Herbacitrin Inhibits HIV-1 Replication through Simultaneous Integrase and Reverse Transcriptase Inhibition

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Éva Áy ◽  
Attila Hunyadi ◽  
Mária Mezei ◽  
János Minárovits ◽  
Judit Hohmann
Keyword(s):  
Antiviral Activity ◽  
Reverse Transcriptase ◽  
Cell Cultures ◽  
Core Protein ◽  
Integrase Inhibitor ◽  
Host Cells ◽  
Cytotoxic Activities ◽  
Protein Levels ◽  
Hiv 1 ◽  
Antiretroviral Activity

Here we report the evaluation of the antiretroviral effect of two flavonoid 7-O-glucosides, herbacitrin (1) and gossypitrin (2), together with quercetin (3), a well-studied flavonol. Antiviral activity of the flavonoids was assessed by analyzing HIV-1 p24 core protein levels in the supernatants of HIV-1 infected MT-4 and MT-2 cell cultures. The compounds showed mild to weak cytotoxic activities on the host cells; herbacitrin was the strongest in this regard (CC50=27.8 and 63.64 μM on MT-4 and MT-2 cells, respectively). In nontoxic concentrations, herbacitrin and quercetin reduced HIV-1 replication, whereas gossypitrin was ineffective. Herbacitrin was found to inhibit reverse transcriptase at 21.5 μM, while it was a more potent integrase inhibitor already active at 2.15 μM. Therefore, our observations suggest that herbacitrin exerts antiretroviral activity through simultaneously acting on these two targets of HIV-1 and that integrase inhibition might play a major role in this activity.

scholarly journals Antiviral activity of derivatized dextrans on HIV-1 infection of primary macrophages and blood lymphocytes

1997 ◽  
Vol 1362 (1) ◽  
pp. 47-55 ◽  
Author(s):  
Nabila Seddiki ◽  
Elisabeth Mbemba ◽  
Didier Letourneur ◽  
Loyda Ylisastigui ◽  
Abdelaziz Benjouad ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Blood Lymphocytes ◽  
Hiv 1

scholarly journals Towards Inhibition of Vif-APOBEC3G Interaction: Which Protein to Target?

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Iris Cadima-Couto ◽  
Joao Goncalves
Keyword(s):  
Antiviral Activity ◽  
Protein Binding ◽  
Mechanism Of Action ◽  
Cellular Immunity ◽  
Viral Infectivity ◽  
Binding Partners ◽  
Viral Infectivity Factor ◽  
Vif Protein ◽  
Hiv 1 ◽  
Antiretroviral Activity

APOBEC proteins appeared in the cellular battle against HIV-1 as part of intrinsic cellular immunity. The antiretroviral activity of some of these proteins is overtaken by the action of HIV-1 Viral Infectivity Factor (Vif) protein. Since the discovery of APOBEC3G (A3G) as an antiviral factor, many advances have been made to understand its mechanism of action in the cell and how Vif acts in order to counteract its activity. The mainstream concept is that Vif overcomes the innate antiviral activity of A3G by direct protein binding and promoting its degradation via the cellular ubiquitin/proteasomal pathway. Vif may also inhibit A3G through mechanisms independent of proteasomal degradation. Binding of Vif to A3G is essential for its degradation since disruption of this interaction is predicted to stimulate intracellular antiviral immunity. In this paper we will discuss the different binding partners between both proteins as one of the major challenges for the development of new antiviral drugs.

scholarly journals In Vitro Antiviral Activity and Cross-Resistance Profile of PL-100, a Novel Protease Inhibitor of Human Immunodeficiency Virus Type 1

2007 ◽  
Vol 51 (11) ◽  
pp. 4036-4043 ◽  
Author(s):  
Serge Dandache ◽  
Guy Sévigny ◽  
Jocelyn Yelle ◽  
Brent R. Stranix ◽  
Neil Parkin ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Antiviral Activity ◽  
Highly Active Antiretroviral Therapy ◽  
Cross Resistance ◽  
Drug Resistant ◽  
Resistance Profile ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Despite the success of highly active antiretroviral therapy, the current emergence and spread of drug-resistant variants of human immunodeficiency virus (HIV) stress the need for new inhibitors with distinct properties. We designed, produced, and screened a library of compounds based on an original l-lysine scaffold for their potentials as HIV type 1 (HIV-1) protease inhibitors (PI). One candidate compound, PL-100, emerged as a specific and noncytotoxic PI that exhibited potent inhibition of HIV-1 protease and viral replication in vitro (Ki , ∼36 pM, and 50% effective concentration [EC50], ∼16 nM, respectively). To confirm that PL-100 possessed a favorable resistance profile, we performed a cross-resistance study using a panel of 63 viral strains from PI-experienced patients selected for the presence of primary PI mutations known to confer resistance to multiple PIs now in clinical use. The results showed that PL-100 retained excellent antiviral activity against almost all of these PI-resistant viruses and that its performance in this regard was superior to those of atazanavir, amprenavir, indinavir, lopinavir, nelfinavir, and saquinavir. In almost every case, the increase in the EC50 for PL-100 observed with viruses containing multiple mutations in protease was far less than that obtained with the other drugs tested. These data underscore the potential for PL-100 to be used in the treatment of drug-resistant HIV disease and argue for its further development.

scholarly journals Safety, pharmacokinetics and antiviral activity of PGT121, a broadly neutralizing monoclonal antibody against HIV-1: a randomized, placebo-controlled, phase 1 clinical trial

2021 ◽  
Author(s):  
Kathryn E. Stephenson ◽  
Boris Julg ◽  
C. Sabrina Tan ◽  
Rebecca Zash ◽  
Stephen R. Walsh ◽  
...  
Keyword(s):  
Viral Load ◽  
T Cell ◽  
Adverse Events ◽  
Antiviral Activity ◽  
Controlled Trial ◽  
Phase 1 ◽  
Serious Adverse Events ◽  
Double Blind ◽  
Cell Counts ◽  
Hiv 1

AbstractHuman immunodeficiency virus (HIV)-1-specific broadly neutralizing monoclonal antibodies are currently under development to treat and prevent HIV-1 infection. We performed a single-center, randomized, double-blind, dose-escalation, placebo-controlled trial of a single administration of the HIV-1 V3-glycan-specific antibody PGT121 at 3, 10 and 30 mg kg–1 in HIV-uninfected adults and HIV-infected adults on antiretroviral therapy (ART), as well as a multicenter, open-label trial of one infusion of PGT121 at 30 mg kg–1 in viremic HIV-infected adults not on ART (no. NCT02960581). The primary endpoints were safety and tolerability, pharmacokinetics (PK) and antiviral activity in viremic HIV-infected adults not on ART. The secondary endpoints were changes in anti-PGT121 antibody titers and CD4+ T-cell count, and development of HIV-1 sequence variations associated with PGT121 resistance. Among 48 participants enrolled, no treatment-related serious adverse events, potential immune-mediated diseases or Grade 3 or higher adverse events were reported. The most common reactions among PGT121 recipients were intravenous/injection site tenderness, pain and headache. Absolute and relative CD4+ T-cell counts did not change following PGT121 infusion in HIV-infected participants. Neutralizing anti-drug antibodies were not elicited. PGT121 reduced plasma HIV RNA levels by a median of 1.77 log in viremic participants, with a viral load nadir at a median of 8.5 days. Two individuals with low baseline viral loads experienced ART-free viral suppression for ≥168 days following antibody infusion, and rebound viruses in these individuals demonstrated full or partial PGT121 sensitivity. The trial met the prespecified endpoints. These data suggest that further investigation of the potential of antibody-based therapeutic strategies for long-term suppression of HIV is warranted, including in individuals off ART and with low viral load.

scholarly journals Study on Suitable Analysis Method for HIV-1 Non-catalytic Integrase Inhibitor

2020 ◽  
Author(s):  
Ki Hoon Park ◽  
Minjee Kim ◽  
Seoung Eun Bae ◽  
Hee Jung Lee ◽  
Kyung-Chang Kim ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Integrase Inhibitor ◽  
Treatment Method ◽  
Strand Transfer ◽  
Inhibition Assay ◽  
Analysis Method ◽  
Catalytic Core ◽  
Host Chromosome ◽  
Inconsistent Result ◽  
Hiv 1

Abstract Background: Integrase (IN) is an essential protein for HIV replication that catalyzes insertion of the reverse-transcribed viral genome into the host chromosome during the early steps of viral infection. Highly active anti-retroviral therapy (HAART) is a HIV/AIDS treatment method that combines three or more antiviral drugs often formulated from compounds that inhibit the activities of viral reverse transcriptase and protease enzymes. Early IN inhibitors (INIs) mainly serve as integrase strand transfer inhibitors (INSTI) that disrupt strand transfer by binding the catalytic core domain (CCD) of IN. However, mutations of IN can confer resistance to INSTI. Therefore, non-catalytic integrase inhibitors (NCINI) have been developed as next-generation INIs. Methods: In this study, we evaluated and compared the activity of INSTI and NCINI according to the analysis method. Antiviral activity was compared using p24 ELISA with MT2 cell and TZM-bl luciferase system with TZM-bl cell. Each drug was serially diluted and treated to MT2 and TZM-b1 cells, infected with HIV-1 AD8 strain and incubated for 5 and 2 days, respectively. Additionally, to analyze properties of INSTI and NCINI, transfer inhibition assay and 3'-processing inhibition assay were performed. Results: During screening of INIs using the p24 ELISA and TZM-bl luciferase systems, we found an inconsistent result with INSTI and NCINI drugs. Following infection of MT2 and TZM-bl cells with T-tropic HIV-1 strain, both INSTI and NCINI treatments induced significant p24 reduction in MT2 cells. However, NCINI showed no antiviral activity in the TZM-bl luciferase system, indicating that this widely used and convenient antiretroviral assay is not suitable for screening of NCINI compounds that target the second round of HIV-1 replication. Conclusion: Accordingly, we recommend application of other assay procedures, such as p24 ELISA or reverse transcription activity, in lieu of the TZM-bl luciferase system for preliminary NCINI drug screening. Utilization of appropriate analytical methods based on underlying mechanisms is necessary for accurate assessment of drug efficacy.

scholarly journals Trimeric heptad repeat synthetic peptides HR1 and HR2 efficiently inhibit HIV-1 entry

2019 ◽  
Vol 39 (9) ◽  
Author(s):  
Olfa Mzoughi ◽  
Meritxell Teixido ◽  
Rémi Planès ◽  
Manutea Serrero ◽  
Ibtissem Hamimed ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Heptad Repeat ◽  
Fusion Activity ◽  
Helical Structures ◽  
Fusion Inhibitors ◽  
Immunodeficiency Virus ◽  
Antiviral Activities ◽  
Physical Interactions ◽  
Kinetics Of ◽  
Hiv 1

Abstract The trimeric heptad repeat domains HR1 and HR2 of the human immunodeficiency virus 1 (HIV-1) gp41 play a key role in HIV-1-entry by membrane fusion. To develop efficient inhibitors against this step, the corresponding trimeric-N36 and C34 peptides were designed and synthesized. Analysis by circular dichroism of monomeric and trimeric N36 and C34 peptides showed their capacities to adopt α-helical structures and to establish physical interactions. At the virological level, while trimeric-C34 conserves the same high anti-fusion activity as monomeric-C34, trimerization of N36-peptide induced a significant increase, reaching 500-times higher in anti-fusion activity, against R5-tropic virus-mediated fusion. This result was associated with increased stability of the N36 trimer peptide with respect to the monomeric form, as demonstrated by the comparative kinetics of their antiviral activities during 6-day incubation in a physiological medium. Collectively, our findings demonstrate that while the trimerization of C34 peptide had no beneficial effect on its stability and antiviral activity, the trimerization of N36 peptide strengthened both stability and antiviral activity. This approach, promotes trimers as new promising HIV-1 inhibitors and point to future development aimed toward innovative peptide fusion inhibitors, microbicides or as immunogens.

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