scholarly journals Endoribonuclease-Prepared Short Interfering RNAs Induce Effective and Specific Inhibition of Human Immunodeficiency Virus Type 1 Replication

2007 ◽  
Vol 81 (19) ◽  
pp. 10680-10686 ◽  
Author(s):  
Mireia Gimenez-Barcons ◽  
Bonaventura Clotet ◽  
Miguel Angel Martinez
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Viral Escape ◽  
Viral Inhibition ◽  
Rnase Iii ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Short interfering RNAs (siRNAs) targeting viral or cellular genes can efficiently inhibit human immunodeficiency virus type 1 (HIV-1) replication. Nevertheless, optimal HIV-1 gene silencing by siRNA requires precise complementarity with most of the target sequence. The emergence of mutations in the targeted gene could lead to rapid viral escape from the siRNA. In the present study, Escherichia coli endoribonuclease III (RNase III) or mammalian Dicer was used to cleave double-stranded RNA into endoribonuclease-prepared siRNA (esiRNA). esiRNAs generate a variety of siRNAs which can efficiently and specifically target multiple sites in the cognate RNA. esiRNAs targeting the region encoding the HIV-1 reverse transcriptase (RT) reduced viral replication by 90%. The inhibition was dose dependent and sequence specific because several irrelevant esiRNAs did not inhibit HIV-1 replication. Importantly, esiRNAs obtained from the prototypic RT sequence of the HXB2 strain and from highly mutated RT sequences showed similar degrees of viral inhibition, suggesting that the heterogeneous population of esiRNAs could overcome individual mismatches in the RT sequence. Finally, esiRNAs generated by Dicer cleavage were five times more potent than those generated by bacterial RNase III digestion. These results show that esiRNAs are potent HIV-1 inhibitors. Moreover, sequence targets do not need to be highly conserved to reach a high level of viral replication inhibition.

scholarly journals Mutually Exclusive T-Cell Receptor Induction and Differential Susceptibility to Human Immunodeficiency Virus Type 1 Mutational Escape Associated with a Two-Amino-Acid Difference between HLA Class I Subtypes

2006 ◽  
Vol 81 (4) ◽  
pp. 1619-1631 ◽  
Author(s):  
Xu G. Yu ◽  
Mathias Lichterfeld ◽  
Senica Chetty ◽  
Katie L. Williams ◽  
Stanley K. Mui ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Hla Class I ◽  
Viral Escape ◽  
Class I ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The relative contributions of HLA alleles and T-cell receptors (TCRs) to the prevention of mutational viral escape are unclear. Here, we examined human immunodeficiency virus type 1 (HIV-1)-specific CD8+ T-cell responses restricted by two closely related HLA class I alleles, B*5701 and B*5703, that differ by two amino acids but are both associated with a dominant response to the same HIV-1 Gag epitope KF11 (KAFSPEVIPMF). When this epitope is presented by HLA-B*5701, it induces a TCR repertoire that is highly conserved among individuals, cross-recognizes viral epitope variants, and is rarely associated with mutational escape. In contrast, KF11 presented by HLA-B*5703 induces an entirely different, more heterogeneous TCR β-chain repertoire that fails to recognize specific KF11 escape variants which frequently arise in clade C-infected HLA-B*5703+ individuals. These data show the influence of HLA allele subtypes on TCR selection and indicate that extensive TCR diversity is not a prerequisite to prevention of allowable viral mutations.

scholarly journals Impact of Natural Polymorphism within the gp41 Cytoplasmic Tail of Human Immunodeficiency Virus Type 1 on the Intracellular Distribution of Envelope Glycoproteins and Viral Assembly

2006 ◽  
Vol 81 (1) ◽  
pp. 125-140 ◽  
Author(s):  
Marie Lambelé ◽  
Béatrice Labrosse ◽  
Emmanuelle Roch ◽  
Alain Moreau ◽  
Bernard Verrier ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Intracellular Trafficking ◽  
Intracellular Distribution ◽  
Immunodeficiency Virus ◽  
Natural Polymorphism ◽  
Hiv 1

ABSTRACT The motifs involved in the various functions of the human immunodeficiency virus type 1 (HIV-1) gp41 cytoplasmic tail (CT), particularly those related to the intracellular trafficking and assembly of envelope glycoproteins (Env) onto core particles, have generally been assessed with a restricted panel of T-cell laboratory-adapted virus strains. Here, we investigated gp41 CT sequences derived from individuals infected with HIV-1 viruses of various subtypes. We identified four patients harboring HIV variants with a natural polymorphism in the membrane-proximal tyrosine-based signal Y712SPL or the Y802W803 diaromatic motif, which are two major determinants of Env intracellular trafficking. Confocal microscopy showed that the intracellular distribution of Env with a mutation in the tyrosine or diaromatic motif differed from that of Env with no mutation in these motifs. Surprisingly, the gp41 CTs of the primary viruses also had differential effects on the intracellular distribution of Env, independently of mutations in the tyrosine or diaromatic motifs, suggesting the involvement of additional determinants. Furthermore, analyses of virus replication kinetics indicated that the effects of mutations in the tyrosine or diaromatic motifs on viral replication depended on the gp41 CT context. These effects were at least partly due to differences in the efficiency of Env incorporation into virions. Thus, polymorphisms in primary HIV-1 gp41 CTs at the quasispecies or subtype level can influence the intracellular distribution of Env, its incorporation into virions, and viral replication capacity.

scholarly journals Cell-Free versus Cell-to-Cell Infection by Human Immunodeficiency Virus Type 1 and Human T-Lymphotropic Virus Type 1: Exploring the Link among Viral Source, Viral Trafficking, and Viral Replication

2016 ◽  
Vol 90 (17) ◽  
pp. 7607-7617 ◽  
Author(s):  
Hélène Dutartre ◽  
Mathieu Clavière ◽  
Chloé Journo ◽  
Renaud Mahieux
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Lymphocytes ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Viral Escape ◽  
Productive Infection ◽  
T Lymphotropic Virus ◽  
Immunodeficiency Virus ◽  
Hiv 1

Human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type 1 (HTLV-1) are complex retroviruses mainly infecting CD4+T lymphocytes. In addition, antigen-presenting cells such as dendritic cells (DCs) are targetedin vivoby both viruses, although to a lesser extent. Interaction of HIV-1 with DCs plays a key role in viral dissemination from the mucosa to CD4+T lymphocytes present in lymphoid organs. While similar mechanisms may occur for HTLV-1 as well, most HTLV-1 data were obtained from T-cell studies, and little is known regarding the trafficking of this virus in DCs. We first compared the efficiency of cell-free versus cell-associated viral sources of both retroviruses at infecting DCs. We showed that both HIV-1 and HTLV-1 cell-free particles are poorly efficient at productively infecting DCs, except when DC-SIGN has been engaged. Furthermore, while SAMHD-1 accounts for restriction of cell-free HIV-1 infection, it is not involved in HTLV-1 restriction. In addition, cell-free viruses lead mainly to a nonproductive DC infection, leading totrans-infection of T-cells, a process important for HIV-1 spread but not for that of HTLV-1. Finally, we show that T-DC cell-to-cell transfer implies viral trafficking in vesicles that may both increase productive infection of DCs (“cis-infection”) and allow viral escape from immune surveillance. Altogether, these observations allowed us to draw a model of HTLV-1 and HIV-1 trafficking in DCs.

scholarly journals Genetic and Stochastic Influences on the Interaction of Human Immunodeficiency Virus Type 1 and Cytotoxic T Lymphocytes in Identical Twins

2005 ◽  
Vol 79 (24) ◽  
pp. 15368-15375 ◽  
Author(s):  
Otto O. Yang ◽  
Joseph Church ◽  
Christina M. R. Kitchen ◽  
Ryan Kilpatrick ◽  
Ayub Ali ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Viral Evolution ◽  
Identical Twins ◽  
Viral Escape ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) evolves in vivo under selective pressure from CD8+ T-lymphocyte (CTL) responses, which are in turn determined by host and viral genetic factors, such as restricting major histocompatibility complex molecules and the available viral epitope sequences. However, CTL are derived stochastically through the random gene rearrangements to produce T-cell receptors (TCR), and the relative impact of genetic versus stochastic processes on CTL targeting of HIV and immune-driven viral evolution is unclear. Here we evaluate identical twins infected with HIV-1 as neonates from a common blood transfusion, with subsequently similar environmental exposures, thereby allowing controlled comparisons of CTL targeting and viral evolution. Seventeen years after infection, their CTL targeting of HIV-1 was remarkably similar. In contrast, their overall TCR profiles were highly dissimilar, and a dominant epitope was recognized by distinctly different TCR in each twin. Furthermore, their viral epitopes had diverged, and there was ongoing viral phylogenetic divergence between the twins between 12 and 17 years after infection. These results indicate that while CTL targeting is predominately genetically determined, stochastic influences render the interaction of HIV-1 and host immunity, and therefore viral escape and CTL efficacy, unpredictable.

scholarly journals Identification of Sequential Viral Escape Mutants Associated with Altered T-Cell Responses in a Human Immunodeficiency Virus Type 1-Infected Individual

2003 ◽  
Vol 77 (23) ◽  
pp. 12430-12440 ◽  
Author(s):  
Mark J. Geels ◽  
Marion Cornelissen ◽  
Hanneke Schuitemaker ◽  
Kiersten Anderson ◽  
David Kwa ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Load ◽  
T Cell ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Viral Escape ◽  
Ctl Epitopes ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Control of viremia in natural human immunodeficiency virus type 1 (HIV-1) infection in humans is associated with a virus-specific T-cell response. However, still much is unknown with regard to the extent of CD8+ cytotoxic T-lymphocyte (CTL) responses required to successfully control HIV-1 infection and to what extent CTL epitope escape can account for rises in viral load and ultimate progression to disease. In this study, we chose to monitor through full-length genome sequence of replication-competent biological clones the modifications that occurred within predicted CTL epitopes and to identify whether the alterations resulted in epitope escape from CTL recognition. From an extensive analysis of 59 biological HIV-1 clones generated over a period of 4 years from a single individual in whom the viral load was observed to rise, we identified the locations in the genome of five CD8+ CTL epitopes. Fixed mutations were identified within the p17, gp120, gp41, Nef, and reverse transcriptase genes. Using a gamma interferon ELIspot assay, we identified for four of the five epitopes with fixed mutations a complete loss of T-cell reactivity against the wild-type epitope and a partial loss of reactivity against the mutant epitope. These results demonstrate the sequential accumulation of CTL escape in a patient during disease progression, indicating that multiple combinations of T-cell epitopes are required to control viremia.

scholarly journals Unique Acquisition of Cytotoxic T-Lymphocyte Escape Mutants in Infant Human Immunodeficiency Virus Type 1 Infection

2005 ◽  
Vol 79 (18) ◽  
pp. 12100-12105 ◽  
Author(s):  
Thillagavathie Pillay ◽  
Hua-Tang Zhang ◽  
Jan W. Drijfhout ◽  
Nicola Robinson ◽  
Helen Brown ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
T Lymphocyte ◽  
Cytotoxic T Lymphocyte ◽  
Viral Escape ◽  
Immunodeficiency Virus ◽  
Ctl Escape ◽  
Hiv 1

ABSTRACT The role of cytotoxic T-lymphocyte (CTL) escape in rapidly progressive infant human immunodeficiency virus type 1 (HIV-1) infection is undefined. The data presented here demonstrate that infant HIV-1-specific CTL can select for viral escape variants very early in life. These variants, furthermore, may be selected specifically in the infant, despite the same CTL specificity being present in the mother. Additionally, pediatric CTL activity may be compromised both by the transmission of maternal escape variants and by mother-to-child transmission of escape variants that originally arose in the father. The unique acquisition of these CTL escape forms may help to explain the severe nature of some pediatric HIV infections.

scholarly journals Human Immunodeficiency Virus Type 1 Pathogenesis in SCID-hu Mice Correlates with Syncytium-Inducing Phenotype and Viral Replication

2000 ◽  
Vol 74 (7) ◽  
pp. 3196-3204 ◽  
Author(s):  
David Camerini ◽  
Hua-Poo Su ◽  
Graciela Gamez-Torre ◽  
Michael L. Johnson ◽  
Jerome A. Zack ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Threshold Level ◽  
Cytopathic Effects ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
Entry Efficiency

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) patient isolates and molecular clones were used to analyze the determinants responsible for human CD4+ thymocyte depletion in SCID-hu mice. Non-syncytium-inducing, R5 or R3R5 HIV-1 isolates from asymptomatic infected people showed little or no human CD4+ thymocyte depletion in SCID-hu mice, while syncytium-inducing (SI), R5X4 or R3R5X4 HIV-1 isolates from the same individuals, isolated just prior to the onset of AIDS, rapidly and efficiently eliminated CD4-bearing human thymocytes. We have mapped the ability of one SI HIV-1 isolate to eliminate CD4+ human cells in SCID-hu mice to a region of the env gene including the three most amino-terminal variable regions (V1 to V3). We find that for all of the HIV-1 isolates that we studied, a nonlinear relationship exists between viral replication and the depletion of CD4+ cells. This relationship can best be described mathematically with a Hill-type plot indicating that a threshold level of viral replication, at which cytopathic effects begin to be seen, exists for HIV-1 infection of thymus/liver grafts in SCID-hu mice. This threshold level is 1 copy of viral DNA for every 11 cells (95% confidence interval = 1 copy of HIV-1 per 67 cells to 1 copy per 4 cells). Furthermore, while SI viruses more frequently achieve this level of replication, replication above this threshold level correlates best with cytopathic effects in this model system. We used GHOST cells to map the coreceptor specificity and relative entry efficiency of these early- and late-stage patient isolates of HIV-1. Our studies show that coreceptor specificity and entry efficiency are critical determinants of HIV-1 pathogenesis in vivo.

scholarly journals Human Immunodeficiency Virus Type 1-Induced Macrophage Gene Expression Includes the p21 Gene, a Target for Viral Regulation

2005 ◽  
Vol 79 (7) ◽  
pp. 4479-4491 ◽  
Author(s):  
Nancy Vázquez ◽  
Teresa Greenwell-Wild ◽  
Nancy J. Marinos ◽  
William D. Swaim ◽  
Salvador Nares ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Kinase Inhibitor ◽  
Peroxisome Proliferator ◽  
Small Interfering Rnas ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT In contrast to CD4+ T cells, human immunodeficiency virus type 1 (HIV-1)-infected macrophages typically resist cell death, support viral replication, and consequently, may facilitate HIV-1 transmission. To elucidate how the virus commandeers the macrophage's intracellular machinery for its benefit, we analyzed HIV-1-infected human macrophages for virus-induced gene transcription by using multiple parameters, including cDNA expression arrays. HIV-1 infection induced the transcriptional regulation of genes associated with host defense, signal transduction, apoptosis, and the cell cycle, among which the cyclin-dependent kinase inhibitor 1A (CDKN1A/p21) gene was the most prominent. p21 mRNA and protein expression followed a bimodal pattern which was initially evident during the early stages of infection, and maximum levels occurred concomitant with active HIV-1 replication. Mechanistically, viral protein R (Vpr) independently regulates p21 expression, consistent with the reduced viral replication and lack of p21 upregulation by a Vpr-negative virus. Moreover, the treatment of macrophages with p21 antisense oligonucleotides or small interfering RNAs reduced HIV-1 infection. In addition, the synthetic triterpenoid and peroxisome proliferator-activated receptor γ ligand, 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO), which is known to influence p21 expression, suppressed viral replication. These data implicate p21 as a pivotal macrophage facilitator of the viral life cycle. Moreover, regulators of p21, such as CDDO, may provide an interventional approach to modulate HIV-1 replication.

scholarly journals Effective Downregulation of HLA-A*2 and HLA-B*57 by Primary Human Immunodeficiency Virus Type 1 Isolates Cultured from Elite Suppressors

2009 ◽  
Vol 83 (13) ◽  
pp. 6941-6946 ◽  
Author(s):  
Eric Nou ◽  
Yan Zhou ◽  
Damaris D. Nou ◽  
Joel N. Blankson
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Hla Class I ◽  
Elite Controllers ◽  
Hla Class I Molecules ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Elite controllers or suppressors (ES) are human immunodeficiency virus type 1 (HIV-1)-infected patients who control viral replication to <50 copies/ml without antiretroviral therapy. Downregulation of HLA class I molecules is an important mechanism used by HIV-1 to evade the immune system. In this study, we showed that primary isolates from ES are as effective as isolates obtained from patients with progressive HIV-1 disease at downregulating HLA-A*2 and HLA-B*57 molecules on primary CD4+ T cells. Thus, a diminished ability of viral isolates from ES to evade HIV-specific immune responses probably does not contribute to the control of viral replication in these patients.

Sign in / Sign up

Export Citation Format

Share Document