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2.
Nat Immunol ; 20(7): 824-834, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209403

RESUMO

Multiple genome-wide studies have identified associations between outcome of human immunodeficiency virus (HIV) infection and polymorphisms in and around the gene encoding the HIV co-receptor CCR5, but the functional basis for the strongest of these associations, rs1015164A/G, is unknown. We found that rs1015164 marks variation in an activating transcription factor 1 binding site that controls expression of the antisense long noncoding RNA (lncRNA) CCR5AS. Knockdown or enhancement of CCR5AS expression resulted in a corresponding change in CCR5 expression on CD4+ T cells. CCR5AS interfered with interactions between the RNA-binding protein Raly and the CCR5 3' untranslated region, protecting CCR5 messenger RNA from Raly-mediated degradation. Reduction in CCR5 expression through inhibition of CCR5AS diminished infection of CD4+ T cells with CCR5-tropic HIV in vitro. These data represent a rare determination of the functional importance of a genome-wide disease association where expression of a lncRNA affects HIV infection and disease progression.


Assuntos
Regulação da Expressão Gênica , Variação Genética , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1 , RNA Antissenso/genética , RNA Longo não Codificante/genética , Receptores CCR5/genética , Regiões 3' não Traduzidas , Alelos , Biomarcadores , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Membrana Celular/metabolismo , Genes Reporter , Genótipo , Infecções por HIV/metabolismo , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/genética , Prognóstico , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores CCR5/metabolismo , Carga Viral
3.
Proc Natl Acad Sci U S A ; 119(29): e2205498119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858344

RESUMO

HLA class I (HLA-I) allotypes vary widely in their dependence on tapasin (TAPBP), an integral component of the peptide-loading complex, to present peptides on the cell surface. We identified two single-nucleotide polymorphisms that regulate TAPBP messenger RNA (mRNA) expression in Africans, rs111686073 (G/C) and rs59097151 (A/G), located in an AP-2α transcription factor binding site and a microRNA (miR)-4486 binding site, respectively. rs111686073G and rs59097151A induced significantly higher TAPBP mRNA expression relative to the alternative alleles due to higher affinity for AP-2α and abrogation of miR-4486 binding, respectively. These variants associated with lower Plasmodium falciparum parasite prevalence and lower incidence of clinical malaria specifically among individuals carrying tapasin-dependent HLA-I allotypes, presumably by augmenting peptide loading, whereas tapasin-independent allotypes associated with relative protection, regardless of imputed TAPBP mRNA expression levels. Thus, an attenuated course of malaria may occur through enhanced breadth and/or magnitude of antigen presentation, an important consideration when evaluating vaccine efficacy.


Assuntos
Antígenos de Histocompatibilidade Classe I , Malária Falciparum , Proteínas de Membrana Transportadoras , Plasmodium falciparum , Sítios de Ligação , Variação Genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Malária Falciparum/genética , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , MicroRNAs/metabolismo , Peptídeos/imunologia , Plasmodium falciparum/imunologia , RNA Mensageiro/genética , Fator de Transcrição AP-2/metabolismo
4.
PLoS Genet ; 14(1): e1007163, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29329284

RESUMO

The HLA-C gene appears to have evolved in higher primates to serve as a dominant source of ligands for the KIR2D family of inhibitory MHC class I receptors. The expression of NK cell-intrinsic MHC class I has been shown to regulate the murine Ly49 family of MHC class I receptors due to the interaction of these receptors with NK cell MHC in cis. However, cis interactions have not been demonstrated for the human KIR and HLA proteins. We report the discovery of an elaborate NK cell-specific system regulating HLA-C expression, indicating an important role for HLA-C in the development and function of NK cells. A large array of alternative transcripts with differences in intron/exon content are generated from an upstream NK-specific HLA-C promoter, and exon content varies between HLA-C alleles due to SNPs in splice donor/acceptor sites. Skipping of the first coding exon of HLA-C generates a subset of untranslatable mRNAs, and the proportion of untranslatable HLA-C mRNA decreases as NK cells mature, correlating with increased protein expression by mature NK cells. Polymorphism in a key Ets-binding site of the NK promoter has generated HLA-C alleles that lack significant promoter activity, resulting in reduced HLA-C expression and increased functional activity. The NK-intrinsic regulation of HLA-C thus represents a novel mechanism controlling the lytic activity of NK cells during development.


Assuntos
Antígenos HLA-C/genética , Células Matadoras Naturais/fisiologia , Ativação Linfocitária/genética , Alelos , Degranulação Celular/genética , Células Cultivadas , Regulação da Expressão Gênica , Genes MHC Classe I , Células HeLa , Humanos , Células Matadoras Naturais/imunologia
5.
Yale J Biol Med ; 90(2): 331-336, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28656019

RESUMO

Objective: Elite Controllers or Suppressors (ES) are patients who control HIV replication without antiretroviral therapy. In this study, we compared baseline and inducible HIV-1 mRNA levels in CD4+ T cells from ES and chronic progressors (CPs) receiving suppressive antiretroviral therapy. Methods: We quantified basal levels of cell associated HIV-1 mRNA in CD4+ T cells isolated from CPs and ES. Additionally, we measured the fold upregulation of intracellular HIV-mRNA after stimulation of CD4+ T cells with phorbol 12-myristate 13-acetate (PMA) and ionomycin, and quantified the amount of HIV-mRNA levels released into culture supernatant. Results: ES have significantly less cell associated HIV-mRNA per 5x106 cells (p = 0.003); 8 of 10 CPs had quantifiable HIV-1 mRNA at baseline, whereas this was present in only 2 of 10 ES. Upon stimulation with PMA and ionomycin, 4 of 5 CPs and 7 of 9 ES showed increased cell associated HIV-mRNA. Interestingly, released HIV-1 mRNA could be detected in supernatants of CD4+ T cells stimulated with PMA/ionomycin from 5 of 8 ES. Conclusion: Our results demonstrate that while the baseline levels of cell associated HIV-1 mRNA are significantly lower in ES compared to CPs, stimulation of CD4+ T cells results in a comparable relative upregulation of viral transcription.


Assuntos
Linfócitos T CD4-Positivos/química , Infecções por HIV/imunologia , Sobreviventes de Longo Prazo ao HIV , HIV-1 , RNA Mensageiro/análise , RNA Viral/análise , Linfócitos T CD4-Positivos/virologia , DNA Viral/análise , Progressão da Doença , Infecções por HIV/virologia , HIV-1/genética , HIV-1/fisiologia , Humanos
6.
J Virol ; 89(18): 9631-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26178987

RESUMO

UNLABELLED: The "shock and kill" model of human immunodeficiency virus type 1 (HIV-1) eradication involves the induction of transcription of HIV-1 genes in latently infected CD4(+) T cells, followed by the elimination of these infected CD4(+) T cells by CD8(+) T cells or other effector cells. CD8(+) T cells may also be needed to control the spread of new infection if residual infected cells are present at the time combination antiretroviral therapy (cART) is discontinued. In order to determine the time frame needed for CD8(+) T cells to effectively prevent the spread of HIV-1 infection, we examined the kinetics of HIV transcription and virus release in latently infected cells reactivated ex vivo. Isolated resting, primary CD4(+) T cells from HIV-positive (HIV+) subjects on suppressive regimens were found to upregulate cell-associated HIV-1 mRNA within 1 h of stimulation and produce extracellular virus as early as 6 h poststimulation. In spite of the rapid kinetics of virus production, we show that CD8(+) T cells from 2 out of 4 viremic controllers were capable of effectively eliminating reactivated autologous CD4(+) cells that upregulate cell-associated HIV-1 mRNA. The results have implications for devising strategies to prevent rebound viremia due to reactivation of rare latently infected cells that persist after potentially curative therapy. IMPORTANCE: A prominent HIV-1 cure strategy termed "shock and kill" involves the induction of HIV-1 transcription in latently infected CD4(+) T cells with the goal of elimination of these cells by either the cytotoxic T lymphocyte response or other immune cell subsets. However, the cytotoxic T cell response may also be required after curative treatment if residual latently infected cells remain. The kinetics of HIV-1 reactivation indicate rapid upregulation of cell-associated HIV-1 mRNA and a 5-h window between transcription and virus release. Thus, HIV-specific CD8(+) T cell responses likely have a very short time frame to eliminate residual latently infected CD4(+) T cells that become reactivated after discontinuation of antiretroviral therapy following potentially curative treatment strategies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Modelos Imunológicos , Ativação Viral/imunologia , Latência Viral/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Feminino , Infecções por HIV/patologia , Humanos , Masculino , Liberação de Vírus/imunologia
7.
J Infect Dis ; 212(9): 1387-96, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25883388

RESUMO

BACKGROUND: Sensitive assays are needed for detection of residual human immunodeficiency virus (HIV) in patients with undetectable plasma viral loads to determine whether eradication strategies are effective. The gold standard quantitative viral outgrowth assay (QVOA) underestimates the magnitude of the viral reservoir. We sought to determine whether xenograft of leukocytes from HIV type 1 (HIV)-infected patients with undetectable plasma viral loads into immunocompromised mice would result in viral amplification. METHODS: Peripheral blood mononuclear cells or purified CD4(+) T cells from HIV or simian immunodeficiency virus (SIV)-infected subjects with undetectable plasma viral loads were adoptively transferred into NOD.Cg-Prkdc(scid)Il2rg(tm1Wjl)/SzJ (NSG) mice. The mice were monitored for viremia following depletion of human CD8(+) T cells to minimize antiviral activity. In some cases, humanized mice were also treated with activating anti-CD3 antibody. RESULTS: With this murine viral outgrowth assay (MVOA), we successfully amplified replication-competent HIV or SIV from all subjects tested, including 5 HIV-positive patients receiving suppressive antiretroviral therapy (ART) and 6 elite controllers or suppressors who were maintaining undetectable viral loads without ART, including an elite suppressor from whom we were unable to recover virus by QVOA. CONCLUSIONS: Our results suggest that the MVOA has the potential to serve as a powerful tool to identify residual HIV in patients with undetectable viral loads.


Assuntos
Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , Carga Viral , Animais , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Modelos Animais de Doenças , Infecções por HIV/tratamento farmacológico , HIV-1/crescimento & desenvolvimento , Humanos , Interleucina-2/sangue , Leucócitos Mononucleares/virologia , Macaca , Masculino , Camundongos , Vírus da Imunodeficiência Símia/crescimento & desenvolvimento , Vírus da Imunodeficiência Símia/isolamento & purificação , Viremia/veterinária
8.
J Virol ; 88(17): 9789-98, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24942573

RESUMO

UNLABELLED: Elite controllers or suppressors (ESs) are HIV-1-infected individuals who are able to maintain viral loads below the limit of detection of clinical assays without antiretroviral therapy. The mechanisms of virologic control are not fully understood, but ESs have been shown to have a more effective CD8+ T cell response to infected CD4+ T cells than chronic progressors (CPs). While macrophages are another cell type productively infected by HIV-1, few studies have examined the ability of primary effector T cells to suppress HIV-1 replication in these target cells. Here, we compared the ability of unstimulated primary CD4+ and CD8+ effector T cells to suppress viral replication in monocyte-derived macrophages (MDMs) in ESs and CPs. While CD4+ effector T cells were capable of inhibiting viral replication in MDMs, the magnitude of this response was not significantly different between ESs and CPs. In contrast, the CD8+ T cells from ESs were significantly more effective than those from CPs at inhibiting viral replication in MDMs. The CD4+ T cell response was partially mediated by soluble factors, while the CD8+ T cell response required cell-to-cell interaction. Our results suggest that the individual contributions of various effector cells should be considered in rational vaccine design and in ongoing eradication efforts. IMPORTANCE: Elite suppressors are individuals capable of maintaining low-level viremia in HIV-1 infection without antiretroviral drugs. Their T cell responses have been implicated in eliminating infected CD4+ T cells, and as such, elite suppressors may represent a model of a functional cure of HIV-1 infection. Here, we sought to determine whether the suppressive T cell responses against infected CD4+ T cells also apply to infected macrophages by comparing the responses of elite suppressors and HIV-1-positive individuals on highly active antiretroviral therapy (HAART). Our results show that the CD8+ cells but not CD4+ T cells from elite suppressors have a response against infected macrophages superior to the response of CD8+ cells from patients on HAART. Our results suggest that the induction of a CD8+ T cell response effective against infected macrophages is an outcome to consider in rational vaccine design.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Macrófagos/virologia , Replicação Viral , Células Cultivadas , HIV-1/fisiologia , Humanos
9.
Cell Rep Med ; 4(7): 101122, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37467721

RESUMO

The discovery of biomarkers that predict viral rebound after discontinuation of antiretroviral therapy (ART) would significantly contribute to the HIV cure field. We previously initiated ART in 20 rhesus macaques on days 0, 1, 2, and 3 following SIVmac251 infection. After 6 months, we discontinued ART and observed viral rebound in 9 of 20 animals, which provided an opportunity to define peripheral biomarkers on ART that predicted viral rebound following ART discontinuation. We show that interleukin-1 (IL-1), IL-6_JAK_STAT3, IL-10, transforming growth factor ß (TGF-ß), IL-22, and IL-23 signaling and activation of monocyte, macrophage, and antigen processing and presentation pathways during ART suppression correlated with viral rebound. These signatures were validated in a second cohort of macaques. Our data suggest that low levels of antigen and proinflammatory signaling during ART suppression correlate with the presence of a rebound-competent viral reservoir. Interventions that modulate these peripheral biomarkers may be promising candidates to evaluate as potential HIV-1 cure strategies.


Assuntos
Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia/fisiologia , Macaca mulatta , Antirretrovirais/uso terapêutico , Antirretrovirais/farmacologia , Replicação Viral , Infecções por HIV/tratamento farmacológico , Biomarcadores
10.
Sci Transl Med ; 14(667): eabh3351, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36260688

RESUMO

Reversing HIV-1 latency promotes killing of infected cells and is essential for cure strategies; however, no single latency reversing agent (LRA) or LRA combination have been shown to reduce HIV-1 latent reservoir size in persons living with HIV-1 (PLWH). Here, we describe an approach to systematically identify LRA combinations to reactivate latent HIV-1 using genome-wide CRISPR screens. Screens on cells treated with suboptimal concentrations of an LRA can identify host genes whose knockout enhances viral gene expression. Therefore, inhibitors of these genes should synergize with the LRA. We tested this approach using AZD5582, an activator of the noncanonical nuclear factor κB (ncNF-κB) pathway, as an LRA and identified histone deacetylase 2 (HDAC2) and bromodomain-containing protein 2 (BRD2), part of the bromodomain and extra-terminal motif (BET) protein family targeted by BET inhibitors, as potential targets. Using CD4+ T cells from PLWH, we confirmed synergy between AZD5582 and several HDAC inhibitors and between AZD5582 and the BET inhibitor, JQ1. A reciprocal screen using suboptimal concentrations of an HDAC inhibitor as an LRA identified BRD2 and ncNF-κB regulators, especially BIRC2, as synergistic candidates for use in combination with HDAC inhibition. Moreover, we identified and validated additional synergistic drug candidates in latency cell line cells and primary lymphocytes isolated from PLWH. Specifically, the knockout of genes encoding CYLD or YPEL5 displayed synergy with existing LRAs in inducing HIV mRNAs. Our study provides insights into the roles of host factors in HIV-1 reactivation and validates a system for identifying drug combinations for HIV-1 latency reversal.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , HIV-1/metabolismo , Latência Viral , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/metabolismo , NF-kappa B/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Ativação Viral , Linfócitos T CD4-Positivos/metabolismo , Fatores de Transcrição/metabolismo
11.
Nat Commun ; 13(1): 3463, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710819

RESUMO

The latent viral reservoir is the critical barrier for developing an HIV-1 cure. Previous studies have shown that therapeutic vaccination or broadly neutralizing antibody (bNAb) administration, together with a Toll-like receptor 7 (TLR7) agonist, enhanced virologic control or delayed viral rebound, respectively, following discontinuation of antiretroviral therapy (ART) in SIV- or SHIV-infected rhesus macaques. Here we show that the combination of active and passive immunization with vesatolimod may lead to higher rates of post-ART virologic control compared to either approach alone. Therapeutic Ad26/MVA vaccination and PGT121 administration together with TLR7 stimulation with vesatolimod resulted in 70% post-ART virologic control in SHIV-SF162P3-infected rhesus macaques. These data suggest the potential of combining active and passive immunization targeting different immunologic mechanisms as an HIV-1 cure strategy.


Assuntos
Infecções por HIV , HIV-1 , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Infecções por HIV/tratamento farmacológico , Imunização Passiva , Macaca mulatta , Receptor 7 Toll-Like , Carga Viral
12.
Nat Med ; 28(6): 1288-1296, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35551291

RESUMO

HIV-1 therapy with single or dual broadly neutralizing antibodies (bNAbs) has shown viral escape, indicating that at least a triple bNAb therapy may be needed for robust suppression of viremia. We performed a two-part study consisting of a single-center, randomized, double-blind, dose-escalation, placebo-controlled first-in-human trial of the HIV-1 V2-glycan-specific antibody PGDM1400 alone or in combination with the V3-glycan-specific antibody PGT121 in 24 adults without HIV in part 1, as well as a multi-center, open-label trial of the combination of PGDM1400, PGT121 and the CD4-binding-site antibody VRC07-523LS in five viremic adults living with HIV not on antiretroviral therapy (ART) in part 2 ( NCT03205917 ). The primary endpoints were safety, tolerability and pharmacokinetics for both parts and antiviral activity among viremic adults living with HIV and not on ART for part 2 of the study. The secondary endpoints were changes in CD4+ T cell counts and development of HIV-1 sequence variations associated with PGDM1400, PGT121 and VRC07-523LS resistance in part 2. Intravenously administered PGDM1400 was safe and well-tolerated at doses up to 30 mg kg-1 and when given in combination with PGT121 and VRC07-523LS. A single intravenous infusion of 20 mg kg-1 of each of the three antibodies reduced plasma HIV RNA levels in viremic individuals by a maximum mean of 2.04 log10 copies per ml; however, viral rebound occurred in all participants within a median of 20 days after nadir. Rebound viruses demonstrated partial to complete resistance to PGDM1400 and PGT121 in vitro, whereas susceptibility to VRC07-523LS was preserved. Viral rebound occurred despite mean VRC07-523LS serum concentrations of 93 µg ml-1. The trial met the pre-specified endpoints. Our data suggest that future bNAb combinations likely need to achieve broad antiviral activity, while also maintaining high serum concentrations, to mediate viral control.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Adulto , Anticorpos Monoclonais/efeitos adversos , Anticorpos Neutralizantes , Antivirais/uso terapêutico , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-HIV , Humanos , Viremia/tratamento farmacológico
13.
Nat Commun ; 12(1): 1474, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674572

RESUMO

The establishment of a long-lived viral reservoir is the key obstacle for achieving an HIV-1 cure. However, the anatomic, virologic, and immunologic features of the viral reservoir in tissues during antiretroviral therapy (ART) remain poorly understood. Here we present a comprehensive necroscopic analysis of the SIV/SHIV viral reservoir in multiple lymphoid and non-lymphoid tissues from SIV/SHIV-infected rhesus macaques suppressed with ART for one year. Viral DNA is observed broadly in multiple tissues and is comparable in animals that had initiated ART at week 1 or week 52 of infection. In contrast, viral RNA is restricted primarily to lymph nodes. Ongoing viral RNA transcription is not the result of unsuppressed viral replication, as single-genome amplification and subsequent phylogenetic analysis do not show evidence of viral evolution. Gag-specific CD8+ T cell responses are predominantly observed in secondary lymphoid organs in animals chronically infected prior to ART and these responses are dominated by CD69+ populations. Overall, we observe that the viral reservoir in rhesus macaques is widely distributed across multiple tissue sites and that lymphoid tissues act as a site of persistent viral RNA transcription under conditions of long-term ART suppression.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/virologia , Linfonodos/virologia , RNA Viral/genética , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Linfócitos T CD8-Positivos , DNA Viral , Modelos Animais de Doenças , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Linfonodos/imunologia , Tecido Linfoide/virologia , Macaca mulatta , Filogenia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/genética , Carga Viral , Replicação Viral
14.
Front Immunol ; 10: 3034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998314

RESUMO

A complex system regulating HLA-C expression in NK cells, driven by an NK-specific promoter that produces alternatively spliced variants of the 5'-UTR has been recently identified. Exon content of the NK-specific 5'-UTR varies strikingly across HLA-C alleles, with some exons being allele specific. In order to investigate the possibility that allelic variation in the 5'-UTR modulates HLA-C expression levels, cDNAs containing several distinct classes of 5'-UTR were compared. Subtle changes in 5'-UTR content had a significant effect on the expression of HLA-C*03 and HLA-C*12 cDNA clones, suggesting that alternative splicing can fine-tune the level of protein expression. The HLA-C*06 allele was found to be highly expressed in relation to the other alleles studied. However, its increased expression was primarily associated with differences in the peptide-binding groove. Although the impact of allele-specific alternative splicing of NK-Pro transcripts on protein levels can be modest when compared with the effect of changes in peptide-loading, alternative splicing may represent an additional regulatory mechanism to fine-tune HLA-C levels within NK cells in distinct tissue environments or at different stages of maturation in order to achieve optimal levels of missing-self recognition.


Assuntos
Processamento Alternativo/genética , Antígenos HLA-C/genética , Células Matadoras Naturais/imunologia , RNA Mensageiro/genética , Regiões 5' não Traduzidas/genética , Alelos , Linhagem Celular , DNA Complementar/genética , Éxons/genética , Humanos
15.
Science ; 359(6371): 86-90, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29302013

RESUMO

The highly polymorphic human leukocyte antigen (HLA) locus encodes cell surface proteins that are critical for immunity. HLA-A expression levels vary in an allele-dependent manner, diversifying allele-specific effects beyond peptide-binding preference. Analysis of 9763 HIV-infected individuals from 21 cohorts shows that higher HLA-A levels confer poorer control of HIV. Elevated HLA-A expression provides enhanced levels of an HLA-A-derived signal peptide that specifically binds and determines expression levels of HLA-E, the ligand for the inhibitory NKG2A natural killer (NK) cell receptor. HLA-B haplotypes that favor NKG2A-mediated NK cell licensing (i.e., education) exacerbate the deleterious effect of high HLA-A on HIV control, consistent with NKG2A-mediated inhibition impairing NK cell clearance of HIV-infected targets. Therapeutic blockade of HLA-E:NKG2A interaction may yield benefit in HIV disease.


Assuntos
Infecções por HIV/imunologia , HIV/imunologia , Antígenos HLA/metabolismo , Células Matadoras Naturais/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Alelos , Contagem de Linfócito CD4 , Estudos de Coortes , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Antígenos HLA/genética , Humanos , Ligantes , Subfamília C de Receptores Semelhantes a Lectina de Células NK/antagonistas & inibidores , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Sinais Direcionadores de Proteínas , Viremia/imunologia
16.
PLoS One ; 12(5): e0174516, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28467486

RESUMO

BACKGROUND: Some latency-reversing agents (LRAs) inhibit HIV-specific CD8+ T cell responses. In a prior study of protein kinase C (PKC) agonists, we found that bryostatin-1 inhibited elite controller/suppressor (ES) CD8+ T cell suppressive activity whereas prostratin had no effect. Ingenol-B is another PKC agonist with potent LRA activity both by itself and in combination with the bromodomain inhibitor JQ1; however its effect on CD8+ T cell mediated control of HIV-1 replication is unknown. METHODS: CD8+ T cells were isolated from ES and treated with bryostatin-1, prostratin, ingenol-B, and JQ1 as well as a combination of each PKC-agonist with JQ1. The cells were then tested in the viral suppression assay. To assess possible mechanisms of inhibition, CD8+ T cells were treated with the LRAs and analyzed for the expression of various immune cell markers. RESULTS: Ingenol-B had no effect on the ability of ES CD8+ T cells to suppress viral replication, however, the combination of ingenol-B and JQ1 caused a modest, but significant decrease in this suppressive capacity. The mechanism of the inhibitory effect of the JQ1 and ingenol-B combination relative to ingenol-B alone was unclear but the effect appeared to be dose dependent. CONCLUSIONS: Ingenol-B does not inhibit HIV-specific CD8+ T cell responses in vitro. These responses are however modestly inhibited when 100 nMingenol-B is combined with JQ1. Since HIV-specific CD8+ T cell activity may be essential for the eradication of reactivated latently infected cells, the potency of latency-reversal activity of drug combinations must be balanced against the effects of the combinations on HIV-specific CD8+ T cell responses.


Assuntos
Linfócitos T CD8-Positivos/efeitos dos fármacos , Diterpenos/farmacologia , HIV-1/imunologia , Azepinas/administração & dosagem , Azepinas/farmacologia , Linfócitos T CD8-Positivos/imunologia , Morte Celular/efeitos dos fármacos , Diterpenos/administração & dosagem , Relação Dose-Resposta a Droga , Citometria de Fluxo , Humanos , Ativação Linfocitária/efeitos dos fármacos , Triazóis/administração & dosagem , Triazóis/farmacologia
17.
J Virus Erad ; 3(2): 85-89, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28435692

RESUMO

AIMS: Latently infected resting CD4 T cells represent a major barrier to HIV-1 eradication efforts. The standard assays used for measuring this reservoir induce activation of resting CD4 T cells with either phytohaemagglutinin (PHA) with irradiated feeder cells, or with anti-CD3 antibodies. We designed a study to compare the sensitivity of a new assay (based on the stimulation of CD4 T cells with anti-CD3 and anti-CD28 coated microbeads) with that of the traditional PHA- and feeder-based viral outgrowth assay. METHODS: Resting CD4 T cells from 10 HIV-1-infected patients on suppressive combination antiretroviral therapy (cART) regimens were cultured in the traditional PHA/feeders viral outgrowth assay and the new CD3/CD28 bead-based assay. Flow cytometry was used to assess the kinetics of activation of resting CD4 T cells in the two different assays. RESULTS: There was no significant difference in the sensitivity of the two assays. The median frequency of latently infected cells was 0.83 infectious units per million (IUPM) for the PHA/feeders assay and 0.54 IUPM with the CD3/CD28 bead-based assay. However, while virus was obtained from all 10 patients with the traditional PHA/feeders outgrowth assay, no virus was obtained from two of 10 patients with the novel anti-CD3/CD28 bead-based viral outgrowth assay (IUPM < 0.02). CONCLUSION: The new CD3/CD28 bead-based assay has comparable sensitivity to the PHA/feeders assay and does not require the addition of feeders, making it a simpler and less labour-intensive alternative to the standard PHA/feeders-based assay.

18.
EBioMedicine ; 16: 141-149, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28159573

RESUMO

HIV-1 controllers are patients who control HIV-1 viral replication without antiretroviral therapy. Control is achieved very early in the course of infection, but the mechanisms through which viral replication is restricted are not fully understood. We describe a patient who presented with acute HIV-1 infection and was found to have an HIV-1 RNA level of <100copies/mL. She did not have any known protective HLA alleles, but significant immune activation of CD8+ T cells and natural killer (NK) cells was present, and both cell types inhibited viral replication. Virus cultured from this patient replicated as well in vitro as virus isolated from her partner, a patient with AIDS who was the source of transmission. Virologic breakthrough occurred 9months after her initial presentation and was associated with an increase in CD4+ T cell activation levels and a significant decrease in NK cell inhibitory capacity. Remarkably, CD8+ T cell inhibitory capacity was preserved and there were no new escape mutations in targeted Gag epitopes. These findings suggest that fully replication-competent virus can be controlled in acute HIV-1 infection in some patients without protective HLA alleles and that NK cell responses may contribute to this early control of viral replication.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Células Matadoras Naturais/imunologia , Replicação Viral/imunologia , Alelos , Sequência de Aminoácidos , Linfócitos T CD8-Positivos/imunologia , Feminino , Infecções por HIV/virologia , HIV-1/genética , HIV-1/fisiologia , Antígenos HLA/genética , Antígenos HLA/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Homologia de Sequência de Aminoácidos , Fatores de Tempo , Carga Viral/genética , Carga Viral/imunologia , Replicação Viral/genética
19.
EBioMedicine ; 8: 217-229, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27428432

RESUMO

Shock and kill strategies involving the use of small molecules to induce viral transcription in resting CD4+ T cells (shock) followed by immune mediated clearance of the reactivated cells (kill), have been proposed as a method of eliminating latently infected CD4+ T cells. The combination of the histone deacetylase (HDAC) inhibitor romidepsin and protein kinase C (PKC) agonist bryostatin-1 is very effective at reversing latency in vitro. However, we found that primary HIV-1 specific CD8+ T cells were not able to eliminate autologous resting CD4+ T cells that had been reactivated with these drugs. We tested the hypothesis that the drugs affected primary CD8+ T cell function and found that both agents had inhibitory effects on the suppressive capacity of HIV-specific CD8+ T cells from patients who control viral replication without antiretroviral therapy (elite suppressors/controllers). The inhibitory effect was additive and multi-factorial in nature. These inhibitory effects were not seen with prostratin, another PKC agonist, either alone or in combination with JQ1, a bromodomain-containing protein 4 inhibitor. Our results suggest that because of their adverse effects on primary CD8+ T cells, some LRAs may cause immune-suppression and therefore should be used with caution in shock and kill strategies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Latência Viral , Terapia Antirretroviral de Alta Atividade , Biomarcadores , Briostatinas/farmacologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , Depsipeptídeos/farmacologia , Feminino , Infecções por HIV/tratamento farmacológico , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Humanos , Imunomodulação/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Receptores de Antígenos de Linfócitos T/metabolismo , Carga Viral , Ativação Viral
20.
AIDS Res Hum Retroviruses ; 32(10-11): 1097-1099, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27353255

RESUMO

Macrophages are targets of HIV-1 infection, and control of viral replication within these cells may be an important component of a T-cell-based vaccine. Although several studies have analyzed the ability of CD8+ T cells to inhibit viral replication in monocyte-derived macrophages, the effect of T cells on HIV-1-infected tissue macrophages is less clear. We demonstrate here that both CD4+ and CD8+ T-cell effectors from HIV controllers are capable of suppressing viral replication in bronchoalveolar lavage-derived alveolar macrophages. These findings have implications for HIV-1 vaccine and eradication strategies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Macrófagos Alveolares/virologia , Sobreviventes , Replicação Viral , Líquido da Lavagem Broncoalveolar/citologia , HIV-1/fisiologia , Humanos
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