Potential new anti-human immunodeficiency virus type 1 compounds depress virus replication in cultured human macrophages.
Ontology highlight
ABSTRACT:
SUBMITTER: Ewart GD
PROVIDER: S-EPMC415615 | biostudies-other | 2004 Jun
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Heterologous viruses may transactivate or suppress human immunodeficiency virus (HIV)-1 replication. An adenovirus type 5 gene transfer vector (Ad5) HIV-1 vaccine was recently evaluated in a clinical trial, without efficacy. In this context, it is relevant to ask what effect Ad vectors have on HIV-1 replication, particularly in cells that are part of the innate immune system. Infection of HIV-1-infected human alveolar macrophages (AMs) obtained from HIV-1(+) individuals with an Ad vector containing no transgene (AdNull) resulted in dose-responsive inhibition of endogenous HIV-1 replication. HIV-1 replication in normal AMs infected with HIV-1 in vitro was inhibited by AdNull with a similar dose response. Ad reduced AM HIV-1 replication up to 14 days after HIV-1 infection. Fully HIV-1-infected AMs were treated with 3'-azido-3'-deoxythymidine, after which Ad infection still inhibited HIV-1 replication, suggesting a postentry step was affected. Substantial HIV-1 DNA was still produced after Ad infection, as quantified by TaqMan real-time PCR, suggesting that the replication block occurred after reverse transcription. AdNull blocked HIV-1 long terminal repeat (LTR) transcription, as assessed by an vesicular stomatitis virus G protein pseudotyped HIV-1 LTR luciferase construct. The formation of HIV-1 DNA integrated into the host chromosome was not inhibited by Ad, as quantified by a two-step TaqMan real-time PCR assay, implying a postintegration block to HIV-1 replication. These data indicate that Ad vectors are inhibitory to HIV-1 replication in human AMs based, in part, on their ability to inhibit LTR-driven transcription.
| S-EPMC2937233 | biostudies-literature
Project description:Several steps of HIV-1 replication critically depend on cholesterol. HIV infection is associated with profound changes in lipid and lipoprotein metabolism and an increased risk of coronary artery disease. Whereas numerous studies have investigated the role of anti-HIV drugs in lipodystrophy and dyslipidemia, the effects of HIV infection on cellular cholesterol metabolism remain uncharacterized. Here, we demonstrate that HIV-1 impairs ATP-binding cassette transporter A1 (ABCA1)-dependent cholesterol efflux from human macrophages, a condition previously shown to be highly atherogenic. In HIV-1-infected cells, this effect was mediated by Nef. Transfection of murine macrophages with Nef impaired cholesterol efflux from these cells. At least two mechanisms were found to be responsible for this phenomenon: first, HIV infection and transfection with Nef induced post-transcriptional down-regulation of ABCA1; and second, Nef caused redistribution of ABCA1 to the plasma membrane and inhibited internalization of apolipoprotein A-I. Binding of Nef to ABCA1 was required for down-regulation and redistribution of ABCA1. HIV-infected and Nef-transfected macrophages accumulated substantial amounts of lipids, thus resembling foam cells. The contribution of HIV-infected macrophages to the pathogenesis of atherosclerosis was supported by the presence of HIV-positive foam cells in atherosclerotic plaques of HIV-infected patients. Stimulation of cholesterol efflux from macrophages significantly reduced infectivity of the virions produced by these cells, and this effect correlated with a decreased amount of virion-associated cholesterol, suggesting that impairment of cholesterol efflux is essential to ensure proper cholesterol content in nascent HIV particles. These results reveal a previously unrecognized dysregulation of intracellular lipid metabolism in HIV-infected macrophages and identify Nef and ABCA1 as the key players responsible for this effect. Our findings have implications for pathogenesis of both HIV disease and atherosclerosis, because they reveal the role of cholesterol efflux impairment in HIV infectivity and suggest a possible mechanism by which HIV infection of macrophages may contribute to increased risk of atherosclerosis in HIV-infected patients.
| S-EPMC1629034 | biostudies-literature
Project description:Heteropolyoxotungstates of the Keggin class containing different heteroatoms were tested for inhibition of two strains of human immunodeficiency virus 1 (HIV-1); they exhibited varying antiviral activity. Compounds containing boron were inactive, only one of those containing phosphorus showed selective anti-viral activity, whereas all silicon-containing compounds exhibited significant anti-viral activity in C8166 cells infected with the IIIB strain. Their effectiveness was some 10-fold higher in JM cells with selectivity indices of about 2000. The silicotungstates were effective inhibitors of HIV reverse transcriptase, showing greater inhibition with RNA/DNA template primers than with DNA/DNA template.primer. Kinetic analysis demonstrated that they inhibit the enzyme by different mechanisms, as, of the four compounds examined, two competed with template.primer and two competed with deoxynucleoside triphosphate. Inhibition of DNA polymerase activity by these compounds was compared using polymerases from different sources, including human; although not necessarily most specific for HIV-1 reverse transcriptase, they did not inhibit all DNA polymerases to a similar degree.
| S-EPMC1136754 | biostudies-other
Project description:Human immunodeficiency virus (HIV) replication in the major natural target cells, CD4+ T lymphocytes and macrophages, is parallel in many aspects of the virus life cycle. However, it differs as to viral assembly and budding, which take place on plasma membranes in T cells and on endosomal membranes in macrophages. It has been postulated that cell type-specific host factors may aid in directing viral assembly to distinct destinations. In this study we defined annexin 2 (Anx2) as a novel HIV Gag binding partner in macrophages. Anx2-Gag binding was confined to productively infected macrophages and was not detected in quiescently infected monocyte-derived macrophages (MDM) in which an HIV replication block was mapped to the late stages of the viral life cycle (A. V. Albright, R. M. Vos, and F. Gonzalez-Scarano, Virology 325:328-339, 2004). We demonstrate that the Anx2-Gag interaction likely occurs at the limiting membranes of late endosomes/multivesicular bodies and that Anx2 depletion is associated with a significant decline in the infectivity of released virions; this coincided with incomplete Gag processing and inefficient incorporation of CD63. Cumulatively, our data suggest that Anx2 is essential for the proper assembly of HIV in MDM.
| S-EPMC1395445 | biostudies-literature
Project description:Triterpene derivatives were analyzed for anti-HIV-1 activity and for cellular toxicity. Betulinic aldehyde, betulinic nitrile, and morolic acid derivatives were identified to have anti-HIV-1 activity. These derivatives inhibit a late step in virus replication, likely virus maturation.
| S-EPMC3053071 | biostudies-literature
Project description:Zika virus infections exhibit recurrent outbreaks and can be responsible for disease complications such as congenital Zika virus syndrome. Effective therapeutic interventions are still a challenge. Antibodies can provide significant protection, although the antibody response may fail due to antibody-dependent enhancement reactions. The choice of the target antigen is a crucial part of the process to generate effective neutralizing antibodies. Human anti-Zika virus antibodies were selected by phage display technology. The antibodies were selected against a mimetic peptide based on the fusion loop region in the protein E of Zika virus, which is highly conserved among different flaviviruses. Four rounds of selection were performed using the synthetic peptide in two strategies: the first was using the acidic elution of bound phages, and the second was by applying a competing procedure. After panning, the selected VH and VL domains were determined by combining NGS and bioinformatic approaches. Three different human monoclonal antibodies were expressed as scFvs and further characterized. All showed a binding capacity to Zika (ZIKV) and showed cross-recognition with yellow fever (YFV) and dengue (DENV) viruses. Two of these antibodies, AZ1p and AZ6m, could neutralize the ZIKV infection in vitro. Due to the conservation of the fusion loop region, these new antibodies can potentially be used in therapeutic intervention against Zika virus and other flavivirus illnesses.
| S-EPMC9321016 | biostudies-literature
Project description:The lentiviral accessory protein Vpx is thought to facilitate the infection of macrophages and dendritic cells by counteracting an unidentified host restriction factor. Although human immunodeficiency virus type 1 (HIV-1) does not encode Vpx, the accessory protein can be provided to monocyte-derived macrophages (MDM) and monocyte-derived dendritic cells (MDDC) in virus-like particles, dramatically enhancing their susceptibility to HIV-1. Vpx and the related accessory protein Vpr are packaged into virions through a virus-specific interaction with the p6 carboxy-terminal domain of Gag. We localized the minimal Vpx packaging motif of simian immunodeficiency virus SIVmac(239) p6 to a 10-amino-acid motif and introduced this sequence into an infectious HIV-1 provirus. The chimeric virus packaged Vpx that was provided in trans and was substantially more infectious on MDDC and MDM than the wild-type virus. We further modified the virus by introducing the Vpx coding sequence in place of nef. The resulting virus produced Vpx and replicated efficiently in MDDC and MDM. The virus also induced a potent type I interferon response in MDDC. In a coculture system, the Vpx-containing HIV-1 was more efficiently transmitted from MDDC to T cells. These findings suggest that in vivo, Vpx may facilitate transmission of the virus from dendritic cells to T cells. In addition, the chimeric virus could be used to design dendritic cell vaccines that induce an enhanced innate immune response. This approach could also be useful in the design of lentiviral vectors that transduce these relatively resistant cells.
| S-EPMC3126535 | biostudies-literature
Project description:Toll-like receptor 3 (TLR3) recognizes double-stranded RNA and induces multiple intracellular events responsible for innate antiviral immunity against viral infections. Here we demonstrate that TLR3 signaling of monocyte-derived macrophages (MDM) from rhesus monkeys by poly I:C inhibited simian immunodeficiency virus (SIV) infection and replication. Investigation of the mechanisms showed that TLR3 activation resulted in the induction of type I and type III interferons (IFNs) and IFN-inducible antiviral factors, including APOBEC3G (A3G), tetherin and SAMHD1. In addition, poly I:C-treated macaque macrophages expressed increased levels of CC chemokines including CCL3, CCL4 and CCL5, the ligands for HIV or SIV coreceptor CCR5. Furthermore, TLR3 signaling of macaque macrophages induced the expression of cellular microRNAs (miR-29a, -29b, -146a and -9), the newly identified intracellular SIV restriction factors. TLR3 activation-mediated anti-SIV effect could be compromised by the knockdown of IRF3 and IRF7. These findings indicate that TLR3-mediated induction of multiple viral restriction factors contribute to the inhibition of SIV infection in macaque macrophages, which support future preclinical studies using rhesus macaques to determine whether in vivo TLR3 activation is safe and beneficial for treating people infected with HIV.
| S-EPMC4258448 | biostudies-literature
Project description:Although rapidly becoming a valuable tool for gene silencing, regulation or editing in vitro, the direct transfer of small interfering ribonucleic acids (siRNAs) into cells is still an unsolved problem for in vivo applications. For the first time, we show that specific modifications of antisense oligomers allow autonomous passage into cell lines and primary cells without further adjuvant or coupling to a cell-penetrating peptide. For this reason, we termed the specifically modified oligonucleotides "cell membrane-crossing oligomers" (CMCOs). CMCOs targeted to various conserved regions of human immunodeficiency virus (HIV)-1 were tested and compared with nontargeting CMCOs. Analyses of uninfected and infected cells incubated with labeled CMCOs revealed that the compounds were enriched in infected cells and some of the tested CMCOs exhibited a potent antiviral effect. Finally, the CMCOs did not exert any cytotoxicity and did not inhibit proliferation of the cells. In vitro, our CMCOs are promising candidates as biologically active anti-HIV reagents for future in vivo applications.
| S-EPMC3276398 | biostudies-literature
Project description:Human immunodeficiency virus type 2 (HIV-2) and simian immunodeficiency virus isolated from a macaque monkey (SIVmac) are assumed to have originated from simian immunodeficiency virus isolated from sooty mangabey (SIVsm). Despite their close similarity in genome structure, HIV-2 and SIVmac show different sensitivities to TRIM5?, a host restriction factor against retroviruses. The replication of HIV-2 strains is potently restricted by rhesus (Rh) monkey TRIM5?, while that of SIVmac strain 239 (SIVmac239) is not. Viral capsid protein is the determinant of this differential sensitivity to TRIM5?, as the HIV-2 mutant carrying SIVmac239 capsid protein evaded Rh TRIM5?-mediated restriction. However, the molecular determinants of this restriction mechanism are unknown. Electrostatic potential on the protein-binding site is one of the properties regulating protein-protein interactions. In this study, we investigated the electrostatic potential on the interaction surface of capsid protein of HIV-2 strain GH123 and SIVmac239. Although HIV-2 GH123 and SIVmac239 capsid proteins share more than 87% amino acid identity, we observed a large difference between the two molecules with the HIV-2 GH123 molecule having predominantly positive and SIVmac239 predominantly negative electrostatic potential on the surface of the loop between ?-helices 4 and 5 (L4/5). As L4/5 is one of the major determinants of Rh TRIM5? sensitivity of these viruses, the present results suggest that the binding site of the Rh TRIM5? may show complementarity to the HIV-2 GH123 capsid surface charge distribution.
| S-EPMC3367459 | biostudies-literature