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Chenine AL, Wieczorek L, Sanders-Buell E, Wesberry M, Towle T, Pillis DM, Molnar S, McLinden R, Edmonds T, Hirsch I, O’Connell R, McCutchan FE, Montefiori DC, Ochsenbauer C, Kappes JC, Kim JH, Polonis VR, Tovanabutra S. Impact of HIV-1 backbone on neutralization sensitivity: neutralization profiles of heterologous envelope glycoproteins expressed in native subtype C and CRF01_AE backbone. PLoS One 2013; 8:e76104. [PMID: 24312165 PMCID: PMC3843658 DOI: 10.1371/journal.pone.0076104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/20/2013] [Indexed: 01/24/2023] Open
Abstract
Standardized assays to assess vaccine and antiviral drug efficacy are critical for the development of protective HIV-1 vaccines and drugs. These immune assays will be advanced by the development of standardized viral stocks, such as HIV-1 infectious molecular clones (IMC), that i) express a reporter gene, ii) are representative of globally diverse subtypes and iii) are engineered to easily exchange envelope (env) genes for expression of sequences of interest. Thus far, a subtype B IMC backbone expressing Renilla luciferase (LucR), and into which the ectodomain of heterologous env coding sequences can be expressed has been successfully developed but as execution of HIV-1 vaccine efficacy trials shifts increasingly to non-subtype B epidemics (Southern African and Southeast Asia), non-subtype B HIV-1 reagents are needed to support vaccine development. Here we describe two IMCs derived from subtypes C and CRF01_AE HIV-1 primary isolates expressing LucR (IMC.LucR) that were engineered to express heterologous gp160 Envs. 18 constructs expressing various subtypes C and CRF01_AE Envs, mostly acute, in subtype-matched and -unmatched HIV backbones were tested for functionality and neutralization sensitivity. Our results suggest a possible effect of non-env HIV-1 genes on the interaction of Env and neutralizing antibodies and highlight the need to generate a library of IMCs representative of the HIV-1 subtype spectrum to be used as standardized neutralization assay reagents for assessing HIV-1 vaccine efficacy.
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Zona L, Lupberger J, Sidahmed-Adrar N, Thumann C, Harris HJ, Barnes A, Florentin J, Tawar RG, Xiao F, Turek M, Durand SC, Duong FHT, Heim MH, Cosset FL, Hirsch I, Samuel D, Brino L, Zeisel MB, Le Naour F, McKeating JA, Baumert TF. HRas signal transduction promotes hepatitis C virus cell entry by triggering assembly of the host tetraspanin receptor complex. Cell Host Microbe 2013; 13:302-13. [PMID: 23498955 DOI: 10.1016/j.chom.2013.02.006] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 01/03/2013] [Accepted: 02/11/2013] [Indexed: 02/07/2023]
Abstract
Hepatitis C virus (HCV) entry is dependent on coreceptor complex formation between the tetraspanin superfamily member CD81 and the tight junction protein claudin-1 (CLDN1) on the host cell membrane. The receptor tyrosine kinase EGFR acts as a cofactor for HCV entry by promoting CD81-CLDN1 complex formation via unknown mechanisms. We identify the GTPase HRas, activated downstream of EGFR signaling, as a key host signal transducer for EGFR-mediated HCV entry. Proteomic analysis revealed that HRas associates with tetraspanin CD81, CLDN1, and the previously unrecognized HCV entry cofactors integrin β1 and Ras-related protein Rap2B in hepatocyte membranes. HRas signaling is required for lateral membrane diffusion of CD81, which enables tetraspanin receptor complex assembly. HRas was also found to be relevant for entry of other viruses, including influenza. Our data demonstrate that viruses exploit HRas signaling for cellular entry by compartmentalization of entry factors and receptor trafficking.
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Stranska R, Florentin J, Dental C, Aouar B, Gondois-Rey F, Durantel D, Baumert TF, Nunes JA, Olive D, Hirsch I. Hepatitis C virus fails to activate NF-kappaB signaling in plasmacytoid dendritic cells. Retrovirology 2012. [PMCID: PMC3360348 DOI: 10.1186/1742-4690-9-s1-o5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Lafont E, Lhermitte L, Chandesris M, Hirsch I, Guichard I, Durieu I, Rétornaz F, Hamidou M, Barete S, Lortholary O, Hermine O, Georgin-Lavialle S. Flushs sans urticaire pigmentaire au cours de la mastocytose systémique : étude de 9 cas. Rev Med Interne 2012. [DOI: 10.1016/j.revmed.2012.10.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Gondois-Rey F, Granjeaud S, Kieu SLT, Herrera D, Hirsch I, Olive D. Multiparametric cytometry for exploration of complex cellular dynamics. Cytometry A 2012; 81:332-42. [PMID: 22278900 DOI: 10.1002/cyto.a.22016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 11/14/2011] [Accepted: 01/01/2012] [Indexed: 12/15/2022]
Abstract
The development of polychromatic cytometry has contributed to significant progress in the field of human immunology. Although numerous functional studies of rare cell populations have been performed using this technology, here we used polychromatic cytometry to explore the dynamics of complex cellular systems implicated in innate immunity. We used PBMC stimulated with live influenza virus as an experimental model. We studied the time course of activation of PBMC, which contain DC, monocytes, and NK cells, all of which are, in addition to their innate immune properties, susceptible to Flu infection. We developed 12 color panels to investigate intracellular expression of IFN-α, TNF-α, IL-12, IL-6, IFN-γ, CD107, and influenza virus nucleoprotein simultaneously in these cell populations. These panels allowed reproducible determination of activation markers induced in DC after their direct exposure to various stimulations or in NK cells by indirect DC-mediated activation within the complex cellular environment. The ability to use a low number of cells and reduced quantities of reagents permitted us to perform kinetic experiments. The power of polychromatic cytometry associated with bioinformatic tools allowed us to analyze the multiple functional data generated as dynamic clustering maps. These maps present a readily understandable view of activation events induced in different populations of PBMC. In addition, it reveals new information on the coordination of the complex pathways induced and on the cellular interactions that sustained indirect DC-mediated NK cell activation. Our work shows that polychromatic cytometry is a tool for discoveries in unexplored complex cell systems, at the crossroads of immunology and virology. © 2012 International Society for Advancement of Cytometry.
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Bozzano F, Picciotto A, Costa P, Marras F, Fazio V, Hirsch I, Olive D, Moretta L, De Maria A. Activating NK cell receptor expression/function (NKp30, NKp46, DNAM-1) during chronic viraemic HCV infection is associated with the outcome of combined treatment. Eur J Immunol 2011; 41:2905-14. [PMID: 21695691 DOI: 10.1002/eji.201041361] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Specific NK cell killer inhibitory receptor (KIR):HLA haplotype combinations have been associated with successful clearance of acute and chronic HCV infection. Whether an imbalance of activating NK cell receptors also contributes to the outcome of treatment of chronic HCV infection, however, is not known. We studied peripheral NK cell phenotype and function in 28 chronically viraemic HCV genotype I treatment-naïve patients who underwent treatment with pegylated IFN-α and ribavirin. At baseline, chronically infected patients with sustained virological response (SVR) had reduced CD56(bright) CD16(+/-) cell populations, increased CD56(dull) CD16(+) NK cell proportions, and lower expression of NKp30, DNAM-1, and CD85j. Similarly, reduced NK cell IFN-γ production but increased degranulation was observed among nonresponding (NR) patients. After treatment, CD56(bright) CD16(+/-) NK cell numbers increased in both SVR and NR patients, with a parallel significant increase in activating NKp30 molecule densities in SVR patients only. In vitro experiments using purified NK cells in the presence of rIL-2 and IFN-α confirmed upregulation of NKp30 and also of NKp46 and DNAM-1 in patients with subsequent SVR. Thus, differences in patient NK cell receptor expression and modulation during chronic HCV-1 infection are associated with subsequent outcome of standard treatment. Individual activating receptor expression/function integrates with KIR:HLA genotype carriage to determine the clearance of HCV infection upon treatment.
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Van Driessche B, Colin L, Guiguen A, Vanhulle C, Blazkova J, Cardona C, Merimi M, Nuttinck M, Twizere JC, Kettmann R, Portetelle D, Burny A, Hirsch I, Rohr O, Van Lint C. DNA cytosine methylation in the Bovine Leukemia Virus promoter is associated with latency in a Lymphoma-derived B-cell line : potential involvement of direct inhibition of CREB/CREM/ATF binding. Retrovirology 2011. [PMCID: PMC3112738 DOI: 10.1186/1742-4690-8-s1-a27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Messal N, Mamessier E, Sylvain A, Celis-Gutierrez J, Thibult ML, Chetaille B, Firaguay G, Pastor S, Guillaume Y, Wang Q, Hirsch I, Nunès JA, Olive D. Differential role for CD277 as a co-regulator of the immune signal in T and NK cells. Eur J Immunol 2011; 41:3443-54. [PMID: 21918970 DOI: 10.1002/eji.201141404] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 07/25/2011] [Accepted: 09/08/2011] [Indexed: 12/21/2022]
Abstract
The human butyrophilin (BTN) 3 or CD277 molecules belong to the B7 family members and are expressed in various immune cells such as T and NK cells. Here, we show that CD277 triggering considerably enhances TCR-induced cytokine production and cell proliferation, even when another co-stimulatory molecule, CD28, is engaged. These CD277-induced additive functional effects are in accordance with the detection of early T-cell activation events such as TCR-induced cell signaling being increased upon CD277 engagement. However, we found that CD277 triggering is not involved in CD16- or NKp46-induced NK cell activation. BTN3/CD277 comprises three structurally related members, BTN3A1, BTN3A2 and BTN3A3. CD277 antibodies recognize all isoforms and we describe a differential expression of BTN3 isoforms between T and NK cells that could explain differential CD277 functions between T and NK cells. Our results show that, while T cells express all BTN3/CD277 transcripts, NK cells express mostly BTN3A2, which lacks the B30.2 intracellular domain. Furthermore, NKp30-induced cytokine production is decreased by the specific engagement of BTN3A2, but not by BTN3A1 triggering. Thus, we provide new insights into the CD277 co-stimulatory pathway that may differentially participate in the regulation of various cell-mediated immune responses.
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Olive D, le Thi S, Xerri L, Hirsch I, A. Nunès J. Rôle de CTLA-4 dans la cosignalisation négative du système immunitaire. Med Sci (Paris) 2011; 27:842-9. [DOI: 10.1051/medsci/20112710012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Trejbalová K, Blazková J, Matousková M, Kucerová D, Pecnová L, Vernerová Z, Herácek J, Hirsch I, Hejnar J. Epigenetic regulation of transcription and splicing of syncytins, fusogenic glycoproteins of retroviral origin. Nucleic Acids Res 2011; 39:8728-39. [PMID: 21771862 PMCID: PMC3203578 DOI: 10.1093/nar/gkr562] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Syncytin-1 and -2, human fusogenic glycoproteins encoded by the env genes of the endogenous retroviral loci ERVWE1 and ERVFRDE1, respectively, contribute to the differentiation of multinucleated syncytiotrophoblast in chorionic villi. In non-trophoblastic cells, however, the expression of syncytins has to be suppressed to avoid potential pathogenic effects. We studied the epigenetic suppression of ERVWE1 and ERVFRDE1 5′-long terminal repeats by DNA methylation and chromatin modifications. Immunoprecipitation of the provirus-associated chromatin revealed the H3K9 trimethylation at transcriptionally inactivated syncytins in HeLa cells. qRT-PCR analysis of non-spliced ERVWE1 and ERVFRDE1 mRNAs and respective env mRNAs detected efficient splicing of endogenously expressed RNAs in trophoblastic but not in non-placental cells. Pointing to the pathogenic potential of aberrantly expressed syncytin-1, we have found deregulation of transcription and splicing of the ERVWE1 in biopsies of testicular seminomas. Finally, ectopic expression experiments suggest the importance of proper chromatin context for the ERVWE1 splicing. Our results thus demonstrate that cell-specific retroviral splicing represents an additional epigenetic level controling the expression of endogenous retroviruses.
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Brichacek B, Vanpouille C, Kiselyeva Y, Biancotto A, Merbah M, Hirsch I, Lisco A, Grivel JC, Margolis L. Contrasting roles for TLR ligands in HIV-1 pathogenesis. PLoS One 2010; 5:e12831. [PMID: 20862220 PMCID: PMC2942834 DOI: 10.1371/journal.pone.0012831] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Accepted: 08/20/2010] [Indexed: 12/23/2022] Open
Abstract
The first line of a host's response to various pathogens is triggered by their engagement of cellular pattern recognition receptors (PRRs). Binding of microbial ligands to these receptors leads to the induction of a variety of cellular factors that alter intracellular and extracellular environment and interfere directly or indirectly with the life cycle of the triggering pathogen. Such changes may also affect any coinfecting microbe. Using ligands to Toll-like receptors (TLRs) 5 and 9, we examined their effect on human immunodeficiency virus (HIV)-1 replication in lymphoid tissue ex vivo. We found marked differences in the outcomes of such treatment. While flagellin (TLR5 agonist) treatment enhanced replication of CC chemokine receptor 5 (CCR 5)-tropic and CXC chemokine receptor 4 (CXCR4)-tropic HIV-1, treatment with oligodeoxynucleotide (ODN) M362 (TLR9 agonist) suppressed both viral variants. The differential effects of these TLR ligands on HIV-1 replication correlated with changes in production of CC chemokines CCL3, CCL4, CCL5, and of CXC chemokines CXCL10, and CXCL12 in the ligand-treated HIV-1-infected tissues. The nature and/or magnitude of these changes were dependent on the ligand as well as on the HIV-1 viral strain. Moreover, the tested ligands differed in their ability to induce cellular activation as evaluated by the expression of the cluster of differentiation markers (CD) 25, CD38, CD39, CD69, CD154, and human leukocyte antigen D related (HLA)-DR as well as of a cell proliferation marker, Ki67, and of CCR5. No significant effect of the ligand treatment was observed on apoptosis and cell death/loss in the treated lymphoid tissue ex vivo. Our results suggest that binding of microbial ligands to TLRs is one of the mechanisms that mediate interactions between coinfected microbes and HIV-1 in human tissues. Thus, the engagement of appropriate TLRs by microbial molecules or their mimetic might become a new strategy for HIV therapy or prevention.
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Hirsch I, Caux C, Hasan U, Bendriss-Vermare N, Olive D. Impaired Toll-like receptor 7 and 9 signaling: from chronic viral infections to cancer. Trends Immunol 2010; 31:391-7. [PMID: 20832362 DOI: 10.1016/j.it.2010.07.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 07/22/2010] [Accepted: 07/28/2010] [Indexed: 12/13/2022]
Abstract
HIV-1, hepatitis B virus, hepatitis C virus, and human papillomavirus type 16 cause persistent infections that frequently precede cancer development. Virions of these viruses are weak inducers of interferon-α and impair Toll-like receptor (TLR)9 function. Loss of TLR9 responsiveness also occurs in tumors without viral etiology such as breast, ovary, and head and neck carcinomas. Recent reports have suggested that viruses and components of the tumor microenviroment interact with regulatory receptors on plasmacytoid dendritic cells (pDCs) to impair TLR7 and TLR9 signaling, and to downregulate TLR9 gene expression. The limited responsiveness of pDCs might contribute to reduced innate immune responses during chronic viral infections and oncogenesis, and represent a target for new therapeutic approaches based on TLR agonists.
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Serriari NE, Gondois-Rey F, Guillaume Y, Remmerswaal EBM, Pastor S, Messal N, Truneh A, Hirsch I, van Lier RAW, Olive D. B and T lymphocyte attenuator is highly expressed on CMV-specific T cells during infection and regulates their function. THE JOURNAL OF IMMUNOLOGY 2010; 185:3140-8. [PMID: 20693422 DOI: 10.4049/jimmunol.0902487] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
B and T lymphocyte attenuator (BTLA), like its relative programmed cell death-1 (PD-1), is a receptor that negatively regulates murine T cell activation. However, its expression and function on human T cells is currently unknown. We report in this study on the expression of BTLA in human T cell subsets as well as its regulation on virus-specific T cells during primary human CMV infection. BTLA is expressed on human CD4(+) T cells during different stages of differentiation, whereas on CD8(+) T cells, it is found on naive T cells and is progressively downregulated in memory and differentiated effector-type cells. During primary CMV infection, BTLA was highly induced on CMV-specific CD8(+) T cells immediately following their differentiation from naive cells. After control of CMV infection, BTLA expression went down on memory CD8(+) cells. Engagement of BTLA by mAbs blocked CD3/CD28-mediated T cell proliferation and Th1 and Th2 cytokine secretion. Finally, in vitro blockade of the BTLA pathway augmented, as efficient as anti-PD-1 mAbs, allogeneic as well as CMV-specific CD8(+) T cell proliferation. Thus, our results suggest that, like PD-1, BTLA provides a potential target for enhancing the functional capacity of CTLs in viral infections.
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Hejnar J, Hirsch I. Reactivation of HIV-1 latent reservoir by an inhibitor of H3K9me2 methyl transferase G9a. Epigenomics 2010; 2:506-507. [PMID: 22232790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
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Pierard V, Guiguen A, Colin L, Wijmeersch G, Vanhulle C, Van Driessche B, Dekoninck A, Blazkova J, Cardona C, Merimi M, Vierendeel V, Calomme C, Nguyên TLA, Nuttinck M, Twizere JC, Kettmann R, Portetelle D, Burny A, Hirsch I, Rohr O, Van Lint C. DNA cytosine methylation in the bovine leukemia virus promoter is associated with latency in a lymphoma-derived B-cell line: potential involvement of direct inhibition of cAMP-responsive element (CRE)-binding protein/CRE modulator/activation transcription factor binding. J Biol Chem 2010; 285:19434-49. [PMID: 20413592 PMCID: PMC2885223 DOI: 10.1074/jbc.m110.107607] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/31/2010] [Indexed: 02/02/2023] Open
Abstract
Bovine leukemia virus (BLV) proviral latency represents a viral strategy to escape the host immune system and allow tumor development. Besides the previously demonstrated role of histone deacetylation in the epigenetic repression of BLV expression, we showed here that BLV promoter activity was induced by several DNA methylation inhibitors (such as 5-aza-2'-deoxycytidine) and that overexpressed DNMT1 and DNMT3A, but not DNMT3B, down-regulated BLV promoter activity. Importantly, cytosine hypermethylation in the 5'-long terminal repeat (LTR) U3 and R regions was associated with true latency in the lymphoma-derived B-cell line L267 but not with defective latency in YR2 cells. Moreover, the virus-encoded transactivator Tax(BLV) decreased DNA methyltransferase expression levels, which could explain the lower level of cytosine methylation observed in the L267(LTaxSN) 5'-LTR compared with the L267 5'-LTR. Interestingly, DNA methylation inhibitors and Tax(BLV) synergistically activated BLV promoter transcriptional activity in a cAMP-responsive element (CRE)-dependent manner. Mechanistically, methylation at the -154 or -129 CpG position (relative to the transcription start site) impaired in vitro binding of CRE-binding protein (CREB) transcription factors to their respective CRE sites. Methylation at -129 CpG alone was sufficient to decrease BLV promoter-driven reporter gene expression by 2-fold. We demonstrated in vivo the recruitment of CREB/CRE modulator (CREM) and to a lesser extent activating transcription factor-1 (ATF-1) to the hypomethylated CRE region of the YR2 5'-LTR, whereas we detected no CREB/CREM/ATF recruitment to the hypermethylated corresponding region in the L267 cells. Altogether, these findings suggest that site-specific DNA methylation of the BLV promoter represses viral transcription by directly inhibiting transcription factor binding, thereby contributing to true proviral latency.
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Florentin J, Dental C, Firaguay G, Gondois-Rey F, Soumelis V, Baumert TF, Nunès JA, Olive D, Hirsch I. Highjacking of PI3K/AKT signaling pathway by Hepatitis C virus in TLR9-activated human plasmacytoid dendritic cells. Retrovirology 2010. [PMCID: PMC3316107 DOI: 10.1186/1742-4690-7-s1-p7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Blazkova J, Trejbalova K, Gondois-Rey F, Philippe H, Patrick P, Verdin E, Olive D, van Lint C, Hejnar J, Hirsch I. CpG methylation controls reactivation of HIV from latency. Retrovirology 2010. [PMCID: PMC3316039 DOI: 10.1186/1742-4690-7-s1-o8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gondois-Rey F, Herrera D, Olive D, Hirsch I. Multicolor flow cytometry analysis of innate responses following in vitro interaction of PBMC with Hepatitis C virus. Retrovirology 2010. [PMCID: PMC3316029 DOI: 10.1186/1742-4690-7-s1-p8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Blazkova J, Trejbalova K, Gondois-Rey F, Halfon P, Philibert P, Guiguen A, Verdin E, Olive D, Van Lint C, Hejnar J, Hirsch I. CpG methylation controls reactivation of HIV from latency. PLoS Pathog 2009; 5:e1000554. [PMID: 19696893 PMCID: PMC2722084 DOI: 10.1371/journal.ppat.1000554] [Citation(s) in RCA: 258] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 07/23/2009] [Indexed: 11/19/2022] Open
Abstract
DNA methylation of retroviral promoters and enhancers localized in the provirus 5' long terminal repeat (LTR) is considered to be a mechanism of transcriptional suppression that allows retroviruses to evade host immune responses and antiretroviral drugs. However, the role of DNA methylation in the control of HIV-1 latency has never been unambiguously demonstrated, in contrast to the apparent importance of transcriptional interference and chromatin structure, and has never been studied in HIV-1-infected patients. Here, we show in an in vitro model of reactivable latency and in a latent reservoir of HIV-1-infected patients that CpG methylation of the HIV-1 5' LTR is an additional epigenetic restriction mechanism, which controls resistance of latent HIV-1 to reactivation signals and thus determines the stability of the HIV-1 latency. CpG methylation acts as a late event during establishment of HIV-1 latency and is not required for the initial provirus silencing. Indeed, the latent reservoir of some aviremic patients contained high proportions of the non-methylated 5' LTR. The latency controlled solely by transcriptional interference and by chromatin-dependent mechanisms in the absence of significant promoter DNA methylation tends to be leaky and easily reactivable. In the latent reservoir of HIV-1-infected individuals without detectable plasma viremia, we found HIV-1 promoters and enhancers to be hypermethylated and resistant to reactivation, as opposed to the hypomethylated 5' LTR in viremic patients. However, even dense methylation of the HIV-1 5'LTR did not confer complete resistance to reactivation of latent HIV-1 with some histone deacetylase inhibitors, protein kinase C agonists, TNF-alpha, and their combinations with 5-aza-2deoxycytidine: the densely methylated HIV-1 promoter was most efficiently reactivated in virtual absence of T cell activation by suberoylanilide hydroxamic acid. Tight but incomplete control of HIV-1 latency by CpG methylation might have important implications for strategies aimed at eradicating HIV-1 infection.
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Gondois-Rey F, Dental C, Halfon P, Baumert TF, Olive D, Hirsch I. Hepatitis C virus is a weak inducer of interferon alpha in plasmacytoid dendritic cells in comparison with influenza and human herpesvirus type-1. PLoS One 2009; 4:e4319. [PMID: 19183807 PMCID: PMC2629532 DOI: 10.1371/journal.pone.0004319] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Accepted: 12/15/2008] [Indexed: 01/27/2023] Open
Abstract
Plasmacytoid dendritic cells (pDCs) are responsible for the production of type I IFN during viral infection. Viral elimination by IFN-α-based therapy in more than 50% of patients chronically infected with hepatitis C virus (HCV) suggests a possible impairment of production of endogenous IFN-α by pDCs in infected individuals. In this study, we investigated the impact of HCV on pDC function. We show that exposure of pDCs to patient serum- and cell culture-derived HCV resulted in production of IFN-α by pDCs isolated from some donors, although this production was significantly lower than that induced by influenza and human herpesvirus type 1 (HHV-1). Using specific inhibitors we demonstrate that endocytosis and endosomal acidification were required for IFN-α production by pDCs in response to cell culture-derived HCV. HCV and noninfectious HCV-like particles inhibited pDC-associated production of IFN-α stimulated with Toll-like receptor 9 (TLR9) agonists (CpG-A or HHV-1) but not that of IFN-α stimulated with TLR7 agonists (resiquimod or influenza virus). The blockade of TLR9-mediated production of IFN-α, effective only when pDCs were exposed to virus prior to or shortly after CpG-A stimulation, was already detectable at the IFN-α transcription level 2 h after stimulation with CpG-A and correlated with down-regulation of the transcription factor IRF7 expression and of TLR9 expression. In conclusion, rapidly and early occurring particle–host cell protein interaction during particle internalization and endocytosis followed by blockade of TLR9 function could result in less efficient sensing of HCV RNA by TLR7, with impaired production of IFN-α. This finding is important for our understanding of HCV-DC interaction and immunopathogenesis of HCV infection.
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Kaufman Y, Hirsch I, Ostrovsky L, Klein O, Pizov R, Lissak A. Pain Relief by Continous Intraperitoneal Nebulization of Ropivacaine during Gynecological Laparoscopic Procedures – A Prospective Randomized Study and Review of the Literature. J Minim Invasive Gynecol 2008. [DOI: 10.1016/j.jmig.2008.09.251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Olive D, Rey J, Collette Y, Carcopino X, Hirsch I. Cancer et agents pathogènes. Med Mal Infect 2008; 38 Suppl 2:S45-6. [DOI: 10.1016/s0399-077x(08)72987-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Biancotto A, Iglehart SJ, Vanpouille C, Condack CE, Lisco A, Ruecker E, Hirsch I, Margolis LB, Grivel JC. HIV-1 induced activation of CD4+ T cells creates new targets for HIV-1 infection in human lymphoid tissue ex vivo. Blood 2007; 111:699-704. [PMID: 17909079 PMCID: PMC2200839 DOI: 10.1182/blood-2007-05-088435] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
We demonstrate mechanisms by which HIV-1 appears to facilitate its own infection in ex vivo-infected human lymphoid tissue. In this system, HIV-1 readily infects various CD4+ T cells, but productive viral infection was supported predominantly by activated T cells expressing either CD25 or HLA-DR or both (CD25/HLA-DR) but not other activation markers: There was a strong positive correlation (r=0.64, P=.001) between virus production and the number of CD25+/HLA-DR+ T cells. HIV-1 infection of lymphoid tissue was associated with activation of both HIV-1-infected and uninfected (bystanders) T cells. In these tissues, apoptosis was selectively increased in T cells expressing CD25/HLA-DR and p24gag but not in cells expressing either of these markers alone. In the course of HIV-1 infection, there was a significant increase in the number of activated (CD25+/HLA-DR+) T cells both infected and uninfected (bystander). By inducing T cells to express particular markers of activation that create new targets for infection, HIV-1 generates in ex vivo lymphoid tissues a vicious destructive circle of activation and infection. In vivo, such self-perpetuating cycle could contribute to HIV-1 disease.
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Kasper HU, Drebber U, Hirsch I, Dienes HP. Morphologische Veränderungen der medikamenteninduzierten Leberschädigung. DER PATHOLOGE 2006; 27:175-81. [PMID: 16583191 DOI: 10.1007/s00292-006-0826-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Hepatotoxicity is a significant complication of therapeutic drug use. As ist can imitate nearly all hepatopathies, the diagnosis of drug-induced liver disease is difficult. Most often, it is a diagnosis of exclusion. The following morphological changes are known, dependent on the target cell type: acute and chronic hepatitis, granuloma formation, and fatty liver disease, cholestatic type acute and chronic liver damage with or without inflammation,or mixed forms of liver injury. Portal or perisinusoidal fibrosis can occur following each type of liver damage. Vascular changes or neoplasms are rare. Drug induced liver injuries are more likely induced by type B damage, which is not expected and cannot be reproduced in animal testing. Type A damage, which is known from toxicity assays, is less likely. A specific therapeutic regime is not available. Therefore, early recognition and cessation of the use of the drug is necessary.
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