scholarly journals Treatment with the Fusion Inhibitor Enfuvirtide Influences the Appearance of Mutations in the Human Immunodeficiency Virus Type 1 Regulatory Protein Rev

2009 ◽  
Vol 53 (7) ◽  
pp. 2816-2823 ◽  
Author(s):  
Valentina Svicher ◽  
Claudia Alteri ◽  
Roberta D'Arrigo ◽  
Alessandro Laganà ◽  
Maria Trignetti ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Life Cycle ◽  
Cell Count ◽  
Regulatory Protein ◽  
Fusion Inhibitor ◽  
Cd4 Cell Count ◽  
Immunodeficiency Virus ◽  
Cd4 Cell ◽  
Hiv 1

ABSTRACT The gp41-encoding sequence of the env gene contains in two separate regions the Rev-responsive elements (RRE) and the alternative open reading frame of the second exon of the regulatory protein Rev. The binding of Rev to the RRE allows the transport of unspliced/singly spliced viral mRNAs out of the nucleus, an essential step in the life cycle of human immunodeficiency virus type 1 (HIV-1). In this study, we have investigated whether the fusion-inhibitor enfuvirtide (ENF) can induce mutations in Rev and if these mutations correlate with the classical ENF resistance gp41 mutations and with viremia and CD4 cell count. Specific Rev mutations were positively associated with ENF treatment and significantly correlated with classical ENF resistance gp41 mutations. In particular, a cluster was observed for the Rev mutations E57A (E57Arev) and N86Srev with the ENF resistance gp41 mutations Q40H (Q40Hgp41) and L45Mgp41. In addition, the presence at week 48 of the E57Arev correlates with a significant viremia increase from baseline to week 48 and with a CD4 cell count loss from baseline to week 48. By modeling the RRE structure, we found that the Q40gp41 and L45gp41 codons form complementary base pairs in a region of the RRE involved in Rev binding. The conformation of this Rev-binding site is disrupted when Q40Hgp41 and L45Mgp41 occur alone while it is restored when both mutations are present. In conclusion, our study shows that ENF pressure may also affect both Rev and RRE structures and can provide an excellent example of compensatory evolution. This highlights the multiple roles of ENF (and perhaps other entry inhibitors) in modulating the correct interplay between the different HIV-1 genes and proteins during the HIV-1 life cycle.

scholarly journals Human Immunodeficiency Virus Type 1 Disease Progression, CCR5 Genotype, and Specific Immune Responses

1998 ◽  
Vol 5 (4) ◽  
pp. 463-466 ◽  
Author(s):  
Ubaldo Visco-Comandini ◽  
Catharina Hultgren ◽  
Christina Broström ◽  
Markus Birk ◽  
Soo Kim ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Immune Responses ◽  
Cell Count ◽  
Disease Progression ◽  
Wild Type ◽  
Cd4 Cell Count ◽  
Immunodeficiency Virus ◽  
Cd4 Cell ◽  
Hiv 1

ABSTRACT The correlation among the presence of a 32-bp deletion in the CC-chemokine receptor 5 (CCR5) gene, disease progression, and human immunodeficiency virus type 1 (HIV-1)-specific immune responses was analyzed for a cohort of 79 Caucasian HIV-1-infected patients. The CCR5 genotype (CCR5/CCR5 = wild type/wild type or Δ32CCR5/CCR5 = 32-bp deletion/wild type) in peripheral blood mononuclear cells was determined by PCR, followed by sequencing of both wild-type and Δ32CCR5 gene fragments. HIV-1-specific humoral responses to gp41 and V3MN peptides were determined by enzyme immunoassays. The prevalence of the Δ32CCR5 allele was lower among 37 patients with rapid progression (progression to AIDS or to a CD4 cell count of <200 × 106/liter in less than 9 years; P < 0.01) compared to that for 42 patients with slow progression (no AIDS and CD4 cell count of >200 × 106/liter after at least 9 years from infection) or to that for 25 non-HIV-1-infected Swedish blood donors (P < 0.05). No differences were observed in the wild-type CCR5sequences between the different groups of patients. For three analyzed patients, the 32-bp Δ32CCR5 gene deletions were identical. The antibody titers against gp41 and a V3MNpeptide in patients with the Δ32CCR5/CCR5 genotype were not significantly different from those in pair-matchedCCR5/CCR5 controls. However, in 13 analyzed patients, a stronger serum neutralizing activity was associated with the Δ32CCR5/CCR5 genotype. Thus, a CCR5/CCR5genotype correlates with a shortened AIDS-free HIV-1 infection period and possibly with a worse neutralizing activity, without an evident influence on the antibody response to two major antigenic regions of HIV-1 envelope.

scholarly journals Frequency of Cytomegalovirus Viral Load in Iranian Human Immunodeficiency Virus-1-Infected Patients with CD4+ Counts <100 Cells/mm3

Intervirology ◽  
2021 ◽  
pp. 1-5
Author(s):  
Mohammad Reza Jabbari ◽  
Hoorieh Soleimanjahi ◽  
Somayeh Shatizadeh Malekshahi ◽  
Mohammad Gholami ◽  
Leila Sadeghi ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Load ◽  
Cell Count ◽  
Previous History ◽  
Cd4 Count ◽  
Cd4 Cell Count ◽  
Cell Counts ◽  
Immunodeficiency Virus ◽  
Cd4 Cell ◽  
Hiv 1

<b><i>Objectives:</i></b> The aim of present work was to assess cytomegalovirus (CMV) viremia in Iranian human immunodeficiency virus (HIV)-1-infected patients with a CD4+ count &#x3c;100 cells/mm<sup>3</sup> and to explore whether CMV DNA loads correlate with CD4+ cell counts or associated retinitis. <b><i>Methods:</i></b> This study was conducted at the AIDS research center in Iran on HIV-1-infected patients with CD4+ count &#x3c;100 cells/mm<sup>3</sup>, antiretroviral therapy-naive, aged ≥18 years with no previous history of CMV end-organ disease (CMV-EOD). <b><i>Results:</i></b> Thirty-nine of 82 patients (47.56%) had detectable CMV viral load ranging from 66 to 485,500 IU/mL. CMV viral load in patients with retinitis ranges from 352 to 2,720 IU/mL, and it was undetectable in 2 patients. No significant associations between CMV viremia and CD4+ cell count was found (<i>p</i> value = 0.31), whereas significant association of CMV viremia in HIV-infected patients with retinitis was found (<i>p</i> &#x3c; 0.02). <b><i>Conclusions:</i></b> We estimated the frequency of CMV viral load infection in Iranian HIV-1-infected patients with a CD4+ cell count &#x3c;100 mm<sup>3</sup>/mL in the largest national referral center for HIV-1 infection in Iran. Further research is required on the relevance of CMV viral load in diagnostic and prognostic value of CMV-EOD.

scholarly journals Neutralizing Antibodies against Autologous Human Immunodeficiency Virus Type 1 Isolates in Patients with Increasing CD4 Cell Counts despite Incomplete Virus Suppression during Antiretroviral Treatment

2001 ◽  
Vol 8 (4) ◽  
pp. 822-824 ◽  
Author(s):  
Loredana Sarmati ◽  
Gabriella d'Ettorre ◽  
Emanuele Nicastri ◽  
Lucia Ercoli ◽  
Ilaria Uccella ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Load ◽  
Cell Count ◽  
Neutralizing Antibodies ◽  
Antiretroviral Treatment ◽  
Cd4 Cell Count ◽  
Cell Counts ◽  
Immunodeficiency Virus ◽  
Cd4 Cell

ABSTRACT Antiretroviral-treated human immunodeficiency virus (HIV) type 1-seropositive individuals can remain clinically stable for a long period of time with an increasing CD4 cell count irrespective of incomplete viral suppression. We evaluated the role of neutralizing antibody (NtAb) activity in the etiopathogenesis of this viro-immunological disconnection (defined as an increasing CD4+-cell count despite a persistent, detectable viral load during antiretroviral therapy) in 33 patients failing therapy with two analogue nucleoside reverse transcriptase inhibitors. An HIV NtAb titer of ≥1:25 was detected in specimens from 16 out of 33 (48%) patients. A significant correlation was found between NtAb titers and CD4+-cell counts (P = 0.001;r = 0.546) but not with HIV RNA levels in plasma. Five patients with a viro-immunological disconnection had an NtAb titer of >1:125, statistically higher than the NtAb titers for the remaining 28 patients with both virologic and immunologic failure (P < 0.0001). The HIV-specific humoral immune response could play a role during antiretroviral treatment to improve immunological function despite an incomplete suppression of viral load.

scholarly journals Hepatitis C treatment uptake and response among human immunodeficiency virus/hepatitis C virus-coinfected patients in a large integrated healthcare system

2019 ◽  
Vol 30 (7) ◽  
pp. 689-695 ◽  
Author(s):  
Jennifer O Lam ◽  
Leo B Hurley ◽  
Scott Chamberland ◽  
Jamila H Champsi ◽  
Laura C Gittleman ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Drug Abuse ◽  
Cell Count ◽  
Hcv Treatment ◽  
Cd4 Cell Count ◽  
Treatment Uptake ◽  
Immunodeficiency Virus ◽  
Cd4 Cell

U.S. guidelines recommend that patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) be prioritized for HCV treatment with direct-acting antiviral agents (DAAs), but the high cost of DAAs may contribute to disparities in treatment uptake and outcomes. We evaluated DAA initiation and effectiveness in HIV/HCV-coinfected patients in a U.S.-based healthcare system during October 2014–December 2017. Of 462 HIV/HCV-coinfected patients, 276 initiated DAAs (70% cumulative proportion treated over three years). Lower likelihood of DAA initiation was observed among patients with Medicare (government-sponsored insurance) versus commercial insurance (adjusted rate ratio [aRR] = 0.62, 95% CI = 0.46–0.84), patients with drug abuse diagnoses (aRR = 0.72, 95% CI = 0.54–0.97), patients with CD4 cell count <200 cells/µl versus ≥500 (aRR = 0.45, 95% CI = 0.23–0.91), and patients without prior HCV treatment (aRR = 0.68, 95% CI = 0.48–0.97). There were no significant differences in DAA initiation by age, gender, race/ethnicity, socioeconomic status, HIV transmission risk, alcohol use, smoking, fibrosis level, HIV RNA levels, antiretroviral therapy use, hepatitis B infection, or number of outpatient visits. Ninety-five percent of patients achieved sustained virologic response (SVR). We found little evidence of sociodemographic disparities in DAA initiation among HIV/HCV-coinfected patients, and SVR rates were high. Efforts are needed to increase DAA uptake among coinfected Medicare enrollees, patients with drug abuse diagnoses, patients with low CD4 cell count, and patients receiving first-time HCV treatment.

scholarly journals Impact of Human Immunodeficiency Virus Type 1 gp41 Amino Acid Substitutions Selected during Enfuvirtide Treatment on gp41 Binding and Antiviral Potency of Enfuvirtide In Vitro

2005 ◽  
Vol 79 (19) ◽  
pp. 12447-12454 ◽  
Author(s):  
M. Mink ◽  
S. M. Mosier ◽  
S. Janumpalli ◽  
D. Davison ◽  
L. Jin ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Amino Acid ◽  
Binding Affinity ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Fusion Inhibitor ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Enfuvirtide (ENF), a novel human immunodeficiency virus type 1 (HIV-1) fusion inhibitor, has potent antiviral activity against HIV-1 both in vitro and in vivo. Resistance to ENF observed after in vitro passaging was associated with changes in a three-amino-acid (aa) motif, GIV, at positions 36 to 38 of gp41. Patients with ongoing viral replication while receiving ENF during clinical trials acquired substitutions within gp41 aa 36 to 45 in the first heptad repeat (HR-1) of gp41 in both population-based plasma virus sequences and proviral DNA sequences from isolates showing reduced susceptibilities to ENF. To investigate their impact on ENF susceptibility, substitutions were introduced into a modified pNL4-3 strain by site-directed mutagenesis, and the susceptibilities of mutant viruses and patient-derived isolates to ENF were tested. In general, susceptibility decreases for single substitutions were lower than those for double substitutions, and the levels of ENF resistance seen for clinical isolates were higher than those observed for the site-directed mutant viruses. The mechanism of ENF resistance was explored for a subset of the substitutions by expressing them in the context of a maltose binding protein chimera containing a portion of the gp41 ectodomain and measuring their binding affinity to fluorescein-labeled ENF. Changes in binding affinity for the mutant gp41 fusion proteins correlated with the ENF susceptibilities of viruses containing the same substitutions. The combined results support the key role of gp41 aa 36 to 45 in the development of resistance to ENF and illustrate that additional envelope regions contribute to the ENF susceptibility of fusion inhibitor-naïve viruses and resistance to ENF.

scholarly journals LFA-1 Antagonists as Agents Limiting Human Immunodeficiency Virus Type 1 Infection and Transmission and Potentiating the Effect of the Fusion Inhibitor T-20

2009 ◽  
Vol 53 (11) ◽  
pp. 4656-4666 ◽  
Author(s):  
Mélanie R. Tardif ◽  
Caroline Gilbert ◽  
Sandra Thibault ◽  
Jean-François Fortin ◽  
Michel J. Tremblay
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Combined Therapy ◽  
Fusion Inhibitor ◽  
Lymphocyte Function ◽  
Virus Propagation ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Adhesion molecules are known to play major roles in the initiation and stabilization of cell-to-cell contacts during the immunological response. Human immunodeficiency virus type 1 (HIV-1) exploits those interactions to facilitate infection and propagation processes. The primary objective of the present study was to investigate the ability of antagonists specific for lymphocyte function-associated antigen 1 (LFA-1) to diminish HIV-1 infection and transmission. We demonstrate here that LFA-1 antagonists can significantly reduce HIV-1 replication in primary human cells and virus propagation by affecting cell-to-cell interactions. Moreover, the inhibition of LFA-1-mediated adhesion events also potentiates the antiviral efficacy of the peptide fusion inhibitor T-20. Altogether, our data suggest that LFA-1 antagonists represent promising antiviral agents. Antiadhesion therapy could be considered a complementary strategy targeting cellular functions essential for HIV-1 spreading and against which the combined therapy currently used displays a limited efficacy.

scholarly journals Interaction between Reverse Transcriptase and Integrase Is Required for Reverse Transcription during HIV-1 Replication

2015 ◽  
Vol 89 (23) ◽  
pp. 12058-12069 ◽  
Author(s):  
Shewit S. Tekeste ◽  
Thomas A. Wilkinson ◽  
Ethan M. Weiner ◽  
Xiaowen Xu ◽  
Jennifer T. Miller ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Life Cycle ◽  
Reverse Transcriptase ◽  
Host Cell ◽  
Reverse Transcription ◽  
Biological Significance ◽  
Binding Surface ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACTHuman immunodeficiency virus type 1 (HIV-1) replication requires reverse transcription of its RNA genome into a double-stranded cDNA copy, which is then integrated into the host cell chromosome. The essential steps of reverse transcription and integration are catalyzed by the viral enzymes reverse transcriptase (RT) and integrase (IN), respectively.In vitro, HIV-1 RT can bind with IN, and the C-terminal domain (CTD) of IN is necessary and sufficient for this binding. To better define the RT-IN interaction, we performed nuclear magnetic resonance (NMR) spectroscopy experiments to map a binding surface on the IN CTD in the presence of RT prebound to a duplex DNA construct that mimics the primer-binding site in the HIV-1 genome. To determine the biological significance of the RT-IN interaction during viral replication, we used the NMR chemical shift mapping information as a guide to introduce single amino acid substitutions of nine different residues on the putative RT-binding surface in the IN CTD. We found that six viral clones bearing such IN substitutions (R231E, W243E, G247E, A248E, V250E, and I251E) were noninfectious. Further analyses of the replication-defective IN mutants indicated that the block in replication took place specifically during early reverse transcription. The recombinant INs purified from these mutants, though retaining enzymatic activities, had diminished ability to bind RT in a cosedimentation assay. The results indicate that the RT-IN interaction is functionally relevant during the reverse transcription step of the HIV-1 life cycle.IMPORTANCETo establish a productive infection, human immunodeficiency virus type 1 (HIV-1) needs to reverse transcribe its RNA genome to create a double-stranded DNA copy and then integrate this viral DNA genome into the chromosome of the host cell. These two essential steps are catalyzed by the HIV-1 enzymes reverse transcriptase (RT) and integrase (IN), respectively. We have shown previously that IN physically interacts with RT, but the importance of this interaction during HIV-1 replication has not been fully characterized. In this study, we have established the biological significance of the HIV-1 RT-IN interaction during the viral life cycle by demonstrating that altering the RT-binding surface on IN disrupts both reverse transcription and viral replication. These findings contribute to our understanding of the RT-IN binding mechanism, as well as indicate that the RT-IN interaction can be exploited as a new antiviral drug target.

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