Impact of suboptimal APOBEC3G neutralization on the emergence of HIV drug resistance in humanized mice

ABSTRACTHIV diversification facilitates immune escape and complicates antiretroviral therapy. In this study, we take advantage of a humanized mouse model to probe the contribution of APOBEC3 mutagenesis to viral evolution. Humanized mice were infected with isogenic HIV molecular clones (HIV-WT, HIV-45G, HIV-ΔSLQ) that differ only in their ability to counteract APOBEC3G (A3G). Infected mice remained naïve or were treated with the RT inhibitor lamivudine (3TC). Viremia, emergence of drug resistant variants and quasispecies diversification in the plasma compartment were determined throughout infection. While both HIV-WT and HIV-45G achieved robust infection, over time HIV-45G replication was significantly reduced compared to HIV-WT in the absence of 3TC treatment. In contrast, treatment response differed significantly between HIV-45G and HIV-WT infected mice. Antiretroviral treatment failed in 91% of HIV-45G infected mice while only 36% of HIV-WT infected mice displayed a similar negative outcome. Emergence of 3TC resistant variants and nucleotide diversity were determined by analyzing 155,462 single HIV reverse transcriptase (RT) and 6,985 vif sequences from 33 mice. Prior to treatment, variants with genotypic 3TC resistance (RT-M184I/V) were detected at low levels in over a third of all animals. Upon treatment, the composition of the plasma quasispecies rapidly changed leading to a majority of circulating viral variants encoding RT-184I. Interestingly, increased viral diversity prior to treatment initiation correlated with higher plasma viremia in HIV-45G but not in HIV-WT infected animals. Taken together, HIV variants with suboptimal anti-A3G activity were attenuated in the absence of selection but display a fitness advantage in the presence of antiretroviral treatment.IMPORTANCEBoth viral (e.g., reverse transcriptase, RT) and host factors (e.g., APOBEC3G (A3G)) can contribute to HIV sequence diversity. This study shows that suboptimal anti-A3G activity shapes viral fitness and drives viral evolution in the plasma compartment of humanized mice.

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Impact of Suboptimal APOBEC3G Neutralization on the Emergence of HIV Drug Resistance in Humanized Mice

Journal of Virology ◽

10.1128/jvi.01543-19 ◽

2019 ◽

Vol 94 (5) ◽

Cited By ~ 1

Author(s):

Matthew M. Hernandez ◽

Audrey Fahrny ◽

Anitha Jayaprakash ◽

Gustavo Gers-Huber ◽

Marsha Dillon-White ◽

...

Keyword(s):

Reverse Transcriptase ◽

Antiretroviral Treatment ◽

Immune Escape ◽

Viral Evolution ◽

Viral Fitness ◽

Humanized Mice ◽

Hiv Reverse Transcriptase ◽

Humanized Mouse Model ◽

Fitness Advantage ◽

Plasma Compartment

ABSTRACT HIV diversification facilitates immune escape and complicates antiretroviral therapy. In this study, we take advantage of a humanized-mouse model to probe the contribution of APOBEC3 mutagenesis to viral evolution. Humanized mice were infected with isogenic HIV molecular clones (HIV-WT, HIV-45G, and HIV-ΔSLQ) that differ in their abilities to counteract APOBEC3G (A3G). Infected mice remained naive or were treated with the reverse transcriptase (RT) inhibitor lamivudine (3TC). Viremia, emergence of drug-resistant variants, and quasispecies diversification in the plasma compartment were determined throughout infection. While both HIV-WT and HIV-45G achieved robust infection, over time, HIV-45G replication was significantly reduced compared to that of HIV-WT in the absence of 3TC treatment. In contrast, treatment responses differed significantly between HIV-45G- and HIV-WT-infected mice. Antiretroviral treatment failed in 91% of HIV-45G-infected mice, while only 36% of HIV-WT-infected mice displayed a similar negative outcome. Emergence of 3TC-resistant variants and nucleotide diversity were determined by analyzing 155,462 single HIV reverse transcriptase gene (RT) and 6,985 vif sequences from 33 mice. Prior to treatment, variants with genotypic 3TC resistance (RT-M184I/V) were detected at low levels in over a third of all the animals. Upon treatment, the composition of the plasma quasispecies rapidly changed, leading to a majority of circulating viral variants encoding RT-184I. Interestingly, increased viral diversity prior to treatment initiation correlated with higher plasma viremia in HIV-45G-infected animals, but not in HIV-WT-infected animals. Taken together, HIV variants with suboptimal anti-A3G activity were attenuated in the absence of selection but displayed a fitness advantage in the presence of antiretroviral treatment. IMPORTANCE Both viral (e.g., RT) and host (e.g., A3G) factors can contribute to HIV sequence diversity. This study shows that suboptimal anti-A3G activity shapes viral fitness and drives viral evolution in the plasma compartment in humanized mice.

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Faculty Opinions recommendation of Dynamic binding orientations direct activity of HIV reverse transcriptase.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1108800.564758 ◽

2008 ◽

Author(s):

Vincent Emery

Keyword(s):

Reverse Transcriptase ◽

Hiv Reverse Transcriptase ◽

Dynamic Binding ◽

Binding Orientations

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New Efavirenz Derivatives and 1,2,3-Triazolyl-phosphonates as Inhibitors of Reverse Transcriptase of HIV-1

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666181029150118 ◽

2018 ◽

Vol 18 (17) ◽

pp. 1494-1505 ◽

Cited By ~ 3

Author(s):

Carolina C.P. Costa ◽

Nubia Boechat ◽

Monica M. Bastos ◽

Fernando de C. da Silva ◽

Andressa Marttorelli ◽

...

Keyword(s):

Reverse Transcriptase ◽

Triazole Ring ◽

Biological Evaluation ◽

World Health ◽

Hiv Reverse Transcriptase ◽

Ic50 Values ◽

Health Organization ◽

Hiv Drugs ◽

Immunodeficiency Syndrome ◽

New Compounds

Background: According to the World Health Organization (WHO), the fight against Acquired Immunodeficiency Syndrome (AIDS) is still one of the most significant challenges facing humanity. Worldwide, it is estimated that 36.7 million people are infected by the Human Immunodeficiency Virus (HIV). Despite the variety of available drugs, the search for new enzymatic inhibitors of HIV is still important due to the presence of adverse effects and the development of resistant strains. Therefore, the present study aimed to design, synthesize, and biologically evaluate novel inhibitors of HIV Reverse Transcriptase (RT). Materials and Methods: These compounds were obtained in two series, and compounds in both series contain a 1,2,3-triazole ring in their structures. The compounds in the first series are Efavirenz (EFV) analogues with the N-1 position substituted by another important fragment as described in the medicinal chemistry literature on anti-HIV drugs. The second series has a phosphonate chain similar to that in the structure of Tenofovir Disoproxil Fumarate (TDF). Results and Conclusion: The results of the biological evaluation showed that all compounds presented high RT inhibition values and lower or comparable inhibitory concentrations (the concentration needed to reduce the enzymatic activity by 50%, IC50 values, 0.8-1.9 µM). Among the compounds in the first series, the three with the lowest IC50 values had values between 0.8-0.9 µM, and of those in the second series, the most potent had an IC50 value of 1.1 µM; compounds in both series were equipotent to TDF (1.2 µM). Thus, the new compounds could be considered lead compounds for the development of new antiretroviral compounds.

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Preclinical platform for long-term evaluation of immuno-oncology drugs using hCD34+ humanized mouse model

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-001513 ◽

2020 ◽

Vol 8 (2) ◽

pp. e001513

Author(s):

Nahee Park ◽

Kamal Pandey ◽

Sei Kyung Chang ◽

Ah-Young Kwon ◽

Young Bin Cho ◽

...

Keyword(s):

Mouse Model ◽

Humanized Mice ◽

Preclinical Models ◽

Humanized Mouse ◽

Humanized Mouse Model ◽

Durable Response ◽

Term Efficacy ◽

Nsg Mice ◽

Oncology Research

BackgroundWell-characterized preclinical models are essential for immune-oncology research. We investigated the feasibility of our humanized mouse model for evaluating the long-term efficacy of immunotherapy and biomarkers.MethodsHumanized mice were generated by injecting human fetal cord blood-derived CD34+ hematopoietic stem cells to NOD-scid IL2rγnull (NSG) mice myeloablated with irradiation or busulfan. The humanization success was defined as a 25% or higher ratio of human CD45+ cells to mice peripheral blood mononuclear cells.ResultsBusulfan was ultimately selected as the appropriate myeloablative method because it provided a higher success rate of humanization (approximately 80%) and longer survival time (45 weeks). We proved the development of functional T cells by demonstrating the anticancer effect of the programmed cell death-1 (PD-1) inhibitor in our humanized mice but not in non-humanized NSG mice. After confirming the long-lasting humanization state (45 weeks), we further investigated the response durability of the PD-1 inhibitor and biomarkers in our humanized mice. Early increase in serum tumor necrosis factor α levels, late increase in serum interleukin 6 levels and increase in tumor-infiltrating CD8+ T lymphocytes correlated more with a durable response over 60 days than with a non-durable response.ConclusionsOur CD34+ humanized mouse model is the first in vivo platform for testing the long-term efficacy of anticancer immunotherapies and biomarkers, given that none of the preclinical models has ever been evaluated for such a long duration.

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Colonization of dermal arterioles by Neisseria meningitidis provides a safe haven from neutrophils

Nature Communications ◽

10.1038/s41467-021-24797-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Valeria Manriquez ◽

Pierre Nivoit ◽

Tomas Urbina ◽

Hebert Echenique-Rivera ◽

Keira Melican ◽

...

Keyword(s):

Neisseria Meningitidis ◽

Inflammatory Infiltrate ◽

Immune Escape ◽

Systemic Disease ◽

Neutrophil Recruitment ◽

Vascular Damage ◽

Bacterial Burden ◽

Human Pathogen ◽

Humanized Mouse ◽

Humanized Mouse Model

AbstractThe human pathogen Neisseria meningitidis can cause meningitis and fatal systemic disease. The bacteria colonize blood vessels and rapidly cause vascular damage, despite a neutrophil-rich inflammatory infiltrate. Here, we use a humanized mouse model to show that vascular colonization leads to the recruitment of neutrophils, which partially reduce bacterial burden and vascular damage. This partial effect is due to the ability of bacteria to colonize capillaries, venules and arterioles, as observed in human samples. In venules, potent neutrophil recruitment allows efficient bacterial phagocytosis. In contrast, in infected capillaries and arterioles, adhesion molecules such as E-Selectin are not expressed on the endothelium, and intravascular neutrophil recruitment is minimal. Our results indicate that the colonization of capillaries and arterioles by N. meningitidis creates an intravascular niche that precludes the action of neutrophils, resulting in immune escape and progression of the infection.

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