Reducing HIV-1 env gene CpG frequency increases the replication capacity of the HXB2 virus strain

ABSTRACT Human immunodeficiency virus type 1 (HIV-1)-infected individuals who develop drug-resistant virus during antiretroviral therapy may derive benefit from continued treatment for two reasons. First, drug-resistant viruses can retain partial susceptibility to the drug combination. Second, therapy selects for drug-resistant viruses that may have reduced replication capacities relative to archived, drug-sensitive viruses. We developed a novel single-cell-level phenotypic assay that allows these two effects to be distinguished and compared quantitatively. Patient-derived gag-pol sequences were cloned into an HIV-1 reporter virus that expresses an endoplasmic reticulum-retained Env-green fluorescent protein fusion. Flow cytometric analysis of single-round infections allowed a quantitative analysis of viral replication over a 4-log dynamic range. The assay faithfully reproduced known in vivo drug interactions occurring at the level of target cells. Simultaneous analysis of single-round infections by wild-type and resistant viruses in the presence and absence of the relevant drug combination divided the benefit of continued nonsuppressive treatment into two additive components, residual virus susceptibility to the drug combination and selection for drug-resistant variants with diminished replication capacities. In some patients with drug resistance, the dominant circulating viruses retained significant susceptibility to the combination. However, in other cases, the dominant drug-resistant viruses showed no residual susceptibility to the combination but had a reduced replication capacity relative to the wild-type virus. In this case, simplification of the regimen might still allow adequate suppression of the wild-type virus. In a third pattern, the resistant viruses had no residual susceptibility to the relevant drug regimen but nevertheless had a replication capacity equivalent to that of wild-type virus. In such cases, there is no benefit to continued treatment. Thus, the ability to simultaneously analyze residual susceptibility and reduced replication capacity of drug-resistant viruses may provide a basis for rational therapeutic decisions in the setting of treatment failure.

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Reverse transcriptase mutation K65N confers a decreased replication capacity to HIV-1 in comparison to K65R due to a decreased RT processivity

Virology ◽

10.1016/j.virol.2011.03.007 ◽

2011 ◽

Vol 414 (1) ◽

pp. 34-41 ◽

Cited By ~ 5

Author(s):

HimaBindu Chunduri ◽

Clyde Crumpacker ◽

Prem L. Sharma

Keyword(s):

Reverse Transcriptase ◽

Replication Capacity ◽

Hiv 1

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HIV-1 fitness and replication capacity: What are they and can they help in patient management?

Current Infectious Disease Reports ◽

10.1007/s11908-003-0068-9 ◽

2003 ◽

Vol 5 (1) ◽

pp. 77-84 ◽

Cited By ~ 5

Author(s):

Frank Maldarelli

Keyword(s):

Patient Management ◽

Replication Capacity ◽

Hiv 1

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Reduced Replication Capacity of NL4-3 Recombinant Viruses Encoding Reverse Transcriptase–Integrase Sequences From HIV-1 Elite Controllers

JAIDS Journal of Acquired Immune Deficiency Syndromes ◽

10.1097/qai.0b013e3181fe9450 ◽

2011 ◽

Vol 56 (2) ◽

pp. 100-108 ◽

Cited By ~ 51

Author(s):

Zabrina L Brumme ◽

Chun Li ◽

Toshiyuki Miura ◽

Jennifer Sela ◽

Pamela C Rosato ◽

...

Keyword(s):

Reverse Transcriptase ◽

Replication Capacity ◽

Elite Controllers ◽

Recombinant Viruses ◽

Hiv 1

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Viral Characteristics Associated with the Clinical Nonprogressor Phenotype Are Inherited by Viruses from a Cluster of HIV-1 Elite Controllers

mBio ◽

10.1128/mbio.02338-17 ◽

2018 ◽

Vol 9 (2) ◽

Cited By ~ 16

Author(s):

Concepción Casado ◽

Sara Marrero-Hernández ◽

Daniel Márquez-Arce ◽

María Pernas ◽

Sílvia Marfil ◽

...

Keyword(s):

Viral Replication ◽

Clinical Phenotype ◽

Functional Characterization ◽

Viral Fitness ◽

Elite Controller ◽

Replication Capacity ◽

Viral Fusion ◽

Elite Controllers ◽

Hiv 1

ABSTRACTA small group of HIV-1-infected individuals, called long-term nonprogressors (LTNPs), and in particular a subgroup of LTNPs, elite controllers (LTNP-ECs), display permanent control of viral replication and lack of clinical progression. This control is the result of a complex interaction of host, immune, and viral factors. We identified, by phylogenetic analysis, a cluster of LTNP-ECs infected with very similar low-replication HIV-1 viruses, suggesting the contribution of common viral features to the clinical LTNP-EC phenotype. HIV-1 envelope (Env) glycoprotein mediates signaling and promotes HIV-1 fusion, entry, and infection, being a key factor of viral fitnessin vitro, cytopathicity, and infection progressionin vivo. Therefore, we isolated full-lengthenvgenes from viruses of these patients and from chronically infected control individuals. Functional characterization of the initial events of the viral infection showed that Envs from the LTNP-ECs were ineffective in the binding to CD4 and in the key triggering of actin/tubulin-cytoskeleton modifications compared to Envs from chronic patients. The viral properties of the cluster viruses result in a defective viral fusion, entry, and infection, and these properties were inherited by every virus of the cluster. Therefore, inefficient HIV-1 Env functions and signaling defects may contribute to the low viral replication capacity and transmissibility of the cluster viruses, suggesting a direct role in the LTNP-EC phenotype of these individuals. These results highlight the important role of viral characteristics in the LTNP-EC clinical phenotype. These Env viral properties were common to all the cluster viruses and thus support the heritability of the viral characteristics.IMPORTANCEHIV-1 long-term nonprogressor elite controller patients, due to their permanent control of viral replication, have been the object of numerous studies to identify the factors responsible for this clinical phenotype. In this work, we analyzed the viral characteristics of the envelopes of viruses from a phylogenetic cluster of LTNP-EC patients. These envelopes showed ineffective binding to CD4 and the subsequent signaling activity to modify actin/tubulin cytoskeletons, which result in low fusion and deficient entry and infection capacities. These Env viral characteristics could explain the nonprogressor clinical phenotype of these patients. In addition, these inefficientenvviral properties were present in all viruses of the cluster, supporting the heritability of the viral phenotype.

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Drug susceptibility and replication capacity of a rare HIV-1 subtype C protease hinge region variant

Antiviral Therapy ◽

10.3851/imp3308 ◽

2019 ◽

Vol 24 (5) ◽

pp. 333-342

Author(s):

Jake Zondagh ◽

Adriaan E Basson ◽

Ikechukwu Achilonu ◽

Lynn Morris ◽

Heini W Dirr ◽

...

Keyword(s):

Drug Susceptibility ◽

Hinge Region ◽

Replication Capacity ◽

Subtype C ◽

Hiv 1

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A Novel MVA-Based HIV Vaccine Candidate (MVA-gp145-GPN) Co-Expressing Clade C Membrane-Bound Trimeric gp145 Env and Gag-Induced Virus-Like Particles (VLPs) Triggered Broad and Multifunctional HIV-1-Specific T Cell and Antibody Responses

Viruses ◽

10.3390/v11020160 ◽

2019 ◽

Vol 11 (2) ◽

pp. 160 ◽

Cited By ~ 4

Author(s):

Beatriz Perdiguero ◽

Cristina Sánchez-Corzo ◽

Carlos Sorzano ◽

Lidia Saiz ◽

Pilar Mediavilla ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Candidate ◽

Hiv Vaccine ◽

Replication Capacity ◽

Virus Like Particles ◽

Modified Vaccinia Virus Ankara ◽

Clade C ◽

Membrane Bound ◽

Hiv 1

The development of an effective Human Immunodeficiency Virus (HIV) vaccine that is able to stimulate both the humoral and cellular HIV-1-specific immune responses remains a major priority challenge. In this study, we described the generation and preclinical evaluation of single and double modified vaccinia virus Ankara (MVA)-based candidates expressing the HIV-1 clade C membrane-bound gp145(ZM96) trimeric protein and/or the Gag(ZM96)-Pol-Nef(CN54) (GPN) polyprotein that was processed to form Gag-induced virus-like particles (VLPs). In vitro characterization of MVA recombinants revealed the stable integration of HIV-1 genes without affecting its replication capacity. In cells that were infected with Env-expressing viruses, the gp145 protein was inserted into the plasma membrane exposing critical epitopes that were recognized by broadly neutralizing antibodies (bNAbs), whereas Gag-induced VLPs were released from cells that were infected with GPN-expressing viruses. VLP particles as well as purified MVA virions contain Env and Gag visualized by immunoelectron microscopy and western-blot of fractions that were obtained after detergent treatments of purified virus particles. In BALB/c mice, homologous MVA-gp145-GPN prime/boost regimen induced broad and polyfunctional Env- and Gag-specific CD4 T cells and antigen-specific T follicular helper (Tfh) and Germinal Center (GC) B cells, which correlated with robust HIV-1-specific humoral responses. Overall, these results support the consideration of MVA-gp145-GPN vector as a potential vaccine candidate against HIV-1.

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HIV-1 virulence, fitness and replication capacity

Therapy ◽

10.2217/14750708.2.1.131 ◽

2005 ◽

Vol 2 (1) ◽

pp. 131-140 ◽

Cited By ~ 1

Author(s):

Eric S Daar

Keyword(s):

Replication Capacity ◽

Hiv 1

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The Human Immunodeficiency Virus Type 1 Nonnucleoside Reverse Transcriptase Inhibitor Resistance Mutation I132M Confers Hypersensitivity to Nucleoside Analogs

Journal of Virology ◽

10.1128/jvi.01968-08 ◽

2009 ◽

Vol 83 (8) ◽

pp. 3826-3833 ◽

Cited By ~ 11

Author(s):

Zandrea Ambrose ◽

Brian D. Herman ◽

Chih-Wei Sheen ◽

Shannon Zelina ◽

Katie L. Moore ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Reverse Transcriptase ◽

Human Immunodeficiency Virus Type ◽

Nucleoside Analogs ◽

Replication Capacity ◽

Immunodeficiency Virus ◽

Viral Replication Capacity ◽

Rt Inhibitors ◽

Hiv 1

ABSTRACT We previously identified a rare mutation in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT), I132M, which confers high-level resistance to the nonnucleoside RT inhibitors (NNRTIs) nevirapine and delavirdine. In this study, we have further characterized the role of this mutation in viral replication capacity and in resistance to other RT inhibitors. Surprisingly, our data show that I132M confers marked hypersusceptibility to the nucleoside analogs lamivudine (3TC) and tenofovir at both the virus and enzyme levels. Subunit-selective mutagenesis studies revealed that the mutation in the p51 subunit of RT was responsible for the increased sensitivity to the drugs, and transient kinetic analyses showed that this hypersusceptibility was due to I132M decreasing the enzyme's affinity for the natural dCTP substrate but increasing its affinity for 3TC-triphosphate. Furthermore, the replication capacity of HIV-1 containing I132M is severely impaired. This decrease in viral replication capacity could be partially or completely compensated for by the A62V or L214I mutation, respectively. Taken together, these results help to explain the infrequent selection of I132M in patients for whom NNRTI regimens are failing and furthermore demonstrate that a single mutation outside of the polymerase active site and inside of the p51 subunit of RT can significantly influence nucleotide selectivity.

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