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1.
Cell ; 184(17): 4401-4413.e10, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34265281

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that escape convalescent and vaccine-induced antibody responses has renewed focus on the development of broadly protective T-cell-based vaccines. Here, we apply structure-based network analysis and assessments of HLA class I peptide stability to define mutationally constrained CD8+ T cell epitopes across the SARS-CoV-2 proteome. Highly networked residues are conserved temporally among circulating variants and sarbecoviruses and disproportionately impair spike pseudotyped lentivirus infectivity when mutated. Evaluation of HLA class I stabilizing activity for 18 globally prevalent alleles identifies CD8+ T cell epitopes within highly networked regions with limited mutational frequencies in circulating SARS-CoV-2 variants and deep-sequenced primary isolates. Moreover, these epitopes elicit demonstrable CD8+ T cell reactivity in convalescent individuals but reduced recognition in recipients of mRNA-based vaccines. These data thereby elucidate key mutationally constrained regions and immunogenic epitopes in the SARS-CoV-2 proteome for a global T-cell-based vaccine against emerging variants and SARS-like coronaviruses.


Asunto(s)
Vacunas contra la COVID-19/inmunología , Epítopos de Linfocito T , Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/química , Antígenos HLA/inmunología , Humanos , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
2.
Nat Immunol ; 24(7): 1087-1097, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37264229

RESUMEN

Human leukocyte antigen (HLA)-E binds epitopes derived from HLA-A, HLA-B, HLA-C and HLA-G signal peptides (SPs) and serves as a ligand for CD94/NKG2A and CD94/NKG2C receptors expressed on natural killer and T cell subsets. We show that among 16 common classical HLA class I SP variants, only 6 can be efficiently processed to generate epitopes that enable CD94/NKG2 engagement, which we term 'functional SPs'. The single functional HLA-B SP, known as HLA-B/-21M, induced high HLA-E expression, but conferred the lowest receptor recognition. Consequently, HLA-B/-21M SP competes with other SPs for providing epitope to HLA-E and reduces overall recognition of target cells by CD94/NKG2A, calling for reassessment of previous disease models involving HLA-B/-21M. Genetic population data indicate a positive correlation between frequencies of functional SPs in humans and corresponding cytomegalovirus mimics, suggesting a means for viral escape from host responses. The systematic, quantitative approach described herein will facilitate development of prediction algorithms for accurately measuring the impact of CD94/NKG2-HLA-E interactions in disease resistance/susceptibility.


Asunto(s)
Células Asesinas Naturales , Señales de Clasificación de Proteína , Humanos , Antígenos de Histocompatibilidad Clase I , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Subfamília D de Receptores Similares a Lectina de las Células NK/genética , Subfamília D de Receptores Similares a Lectina de las Células NK/metabolismo , Lectinas Tipo C/metabolismo , Receptores de Células Asesinas Naturales/metabolismo , Antígenos HLA-E
3.
Annu Rev Immunol ; 29: 295-317, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21219175

RESUMEN

Multiple epidemiological studies have demonstrated associations between the human leukocyte antigen (HLA) loci and human immunodeficiency virus (HIV) disease, and more recently the killer cell immunoglobulin-like (KIR) locus has been implicated in differential responses to the virus. Genome-wide association studies have convincingly shown that the HLA class I locus is the most significant host genetic contributor to the variation in HIV control, underscoring a central role for CD8 T cells in resistance to the virus. However, both genetic and functional data indicate that part of the HLA effect on HIV is due to interactions between KIR and HLA genes, also implicating natural killer cells in defense against viral infection and viral expansion prior to initiation of an adaptive response. We review the HLA and KIR associations with HIV disease and the progress that has been made in understanding the mechanisms that explain these associations.


Asunto(s)
Infecciones por VIH/inmunología , VIH-1 , Antígenos HLA/inmunología , Receptores KIR/inmunología , Animales , Humanos , Linfocitos T/inmunología
4.
Nature ; 620(7976): 1025-1030, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37532928

RESUMEN

HIV-1 remains a global health crisis1, highlighting the need to identify new targets for therapies. Here, given the disproportionate HIV-1 burden and marked human genome diversity in Africa2, we assessed the genetic determinants of control of set-point viral load in 3,879 people of African ancestries living with HIV-1 participating in the international collaboration for the genomics of HIV3. We identify a previously undescribed association signal on chromosome 1 where the peak variant associates with an approximately 0.3 log10-transformed copies per ml lower set-point viral load per minor allele copy and is specific to populations of African descent. The top associated variant is intergenic and lies between a long intergenic non-coding RNA (LINC00624) and the coding gene CHD1L, which encodes a helicase that is involved in DNA repair4. Infection assays in iPS cell-derived macrophages and other immortalized cell lines showed increased HIV-1 replication in CHD1L-knockdown and CHD1L-knockout cells. We provide evidence from population genetic studies that Africa-specific genetic variation near CHD1L associates with HIV replication in vivo. Although experimental studies suggest that CHD1L is able to limit HIV infection in some cell types in vitro, further investigation is required to understand the mechanisms underlying our observations, including any potential indirect effects of CHD1L on HIV spread in vivo that our cell-based assays cannot recapitulate.


Asunto(s)
ADN Helicasas , Proteínas de Unión al ADN , Variación Genética , Infecciones por VIH , VIH-1 , Carga Viral , Humanos , Línea Celular , ADN Helicasas/genética , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Infecciones por VIH/genética , VIH-1/crecimiento & desarrollo , VIH-1/fisiología , Carga Viral/genética , África , Cromosomas Humanos Par 1/genética , Alelos , ARN Largo no Codificante/genética , Replicación Viral
5.
Proc Natl Acad Sci U S A ; 119(29): e2205498119, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858344

RESUMEN

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.


Asunto(s)
Antígenos de Histocompatibilidad Clase I , Malaria Falciparum , Proteínas de Transporte de Membrana , Plasmodium falciparum , Sitios de Unión , Variación Genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Malaria Falciparum/genética , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , MicroARNs/metabolismo , Péptidos/inmunología , Plasmodium falciparum/inmunología , ARN Mensajero/genética , Factor de Transcripción AP-2/metabolismo
7.
Immunogenetics ; 75(3): 263-267, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36449053

RESUMEN

The leukocyte immunoglobulin-like receptor (LILR)B3 and LILRA6 genes encode homologous myeloid inhibitory and activating orphan receptors, respectively. Both genes exhibit a strikingly high level of polymorphism at the amino acid level and LILRA6 (but not LILRB3) displays copy number variation (CNV). Although multiple alleles have been reported for both genes, limited data is available on frequencies of these alleles among humans. We have sequenced LILRB3/A6 exons encoding signal peptides and ectodomains in 91 healthy blood donors of European descent who carry one or two copies of LILRA6 per diploid genome. Analysis of haplotypes among individuals with two LILRA6 copies, representing the majority in this cohort (N = 86), shows that common LILRB3 and LILRA6 alleles encode some distinct amino acid sequences in homologous regions of the receptors, which could potentially impact their respective functions differentially. Comparison of sequences in individuals with one vs. two copies of LILRA6 supports non-allelic homologous recombination between LILRB3 and LILRA6 as a mechanism for generating LILRA6 CNV and LILRB3 diversity. These data characterize LILRB3/LILRA6 genetic variation in more detail than previously described and underscore the need to determine their ligands.


Asunto(s)
Antígenos CD , Variaciones en el Número de Copia de ADN , Pueblo Europeo , Receptores Inmunológicos , Humanos , Alelos , Polimorfismo Genético , Receptores Inmunológicos/genética , Antígenos CD/genética
8.
Immunogenetics ; 75(3): 249-262, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36707444

RESUMEN

Human leukocyte antigen (HLA) class I and II loci are essential elements of innate and acquired immunity. Their functions include antigen presentation to T cells leading to cellular and humoral immune responses, and modulation of NK cells. Their exceptional influence on disease outcome has now been made clear by genome-wide association studies. The exons encoding the peptide-binding groove have been the main focus for determining HLA effects on disease susceptibility/pathogenesis. However, HLA expression levels have also been implicated in disease outcome, adding another dimension to the extreme diversity of HLA that impacts variability in immune responses across individuals. To estimate HLA expression, immunogenetic studies traditionally rely on quantitative PCR (qPCR). Adoption of alternative high-throughput technologies such as RNA-seq has been hampered by technical issues due to the extreme polymorphism at HLA genes. Recently, however, multiple bioinformatic methods have been developed to accurately estimate HLA expression from RNA-seq data. This opens an exciting opportunity to quantify HLA expression in large datasets but also brings questions on whether RNA-seq results are comparable to those by qPCR. In this study, we analyze three classes of expression data for HLA class I genes for a matched set of individuals: (a) RNA-seq, (b) qPCR, and (c) cell surface HLA-C expression. We observed a moderate correlation between expression estimates from qPCR and RNA-seq for HLA-A, -B, and -C (0.2 ≤ rho ≤ 0.53). We discuss technical and biological factors which need to be accounted for when comparing quantifications for different molecular phenotypes or using different techniques.


Asunto(s)
Estudio de Asociación del Genoma Completo , Antígenos de Histocompatibilidad Clase I , Humanos , RNA-Seq , Antígenos de Histocompatibilidad Clase I/genética , Antígenos HLA-C/genética , Reacción en Cadena de la Polimerasa
9.
J Immunol ; 207(12): 2913-2921, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34810222

RESUMEN

CD8+ T cells are key mediators of antiviral and antitumor immunity. The isolation and study of Ag-specific CD8+ T cells, as well as mapping of their MHC restriction, has practical importance to the study of disease and the development of therapeutics. Unfortunately, most experimental approaches are cumbersome, owing to the highly variable and donor-specific nature of MHC-bound peptide/TCR interactions. Here we present a novel system for rapid identification and characterization of Ag-specific CD8+ T cells, particularly well suited for samples with limited primary cells. Cells are stimulated ex vivo with Ag of interest, followed by live cell sorting based on surface-trapped TNF-α. We take advantage of major advances in single-cell sequencing to generate full-length sequence data from the paired TCR α- and ß-chains from these Ag-specific cells. The paired TCR chains are cloned into retroviral vectors and used to transduce donor CD8+ T cells. These TCR transductants provide a virtually unlimited experimental reagent, which can be used for further characterization, such as minimal epitope mapping or identification of MHC restriction, without depleting primary cells. We validated this system using CMV-specific CD8+ T cells from rhesus macaques, characterizing an immunodominant Mamu-A1*002:01-restricted epitope. We further demonstrated the utility of this system by mapping a novel HLA-A*68:02-restricted HIV Gag epitope from an HIV-infected donor. Collectively, these data validate a new strategy to rapidly identify novel Ags and characterize Ag-specific CD8+ T cells, with applications ranging from the study of infectious disease to immunotherapeutics and precision medicine.


Asunto(s)
Linfocitos T CD8-positivos , Infecciones por VIH , Animales , Epítopos , Epítopos de Linfocito T , Macaca mulatta , Receptores de Antígenos de Linfocitos T , Factor de Necrosis Tumoral alfa
10.
Proc Natl Acad Sci U S A ; 117(45): 28232-28238, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33097667

RESUMEN

Human leukocyte antigen (HLA) class I allotypes vary in their ability to present peptides in the absence of tapasin, an essential component of the peptide loading complex. We quantified tapasin dependence of all allotypes that are common in European and African Americans (n = 97), which revealed a broad continuum of values. Ex vivo examination of cytotoxic T cell responses to the entire HIV-1 proteome from infected subjects indicates that tapasin-dependent allotypes present a more limited set of distinct peptides than do tapasin-independent allotypes, data supported by computational predictions. This suggests that variation in tapasin dependence may impact the strength of the immune responses by altering peptide repertoire size. In support of this model, we observed that individuals carrying HLA class I genotypes characterized by greater tapasin independence progress more slowly to AIDS and maintain lower viral loads, presumably due to increased breadth of peptide presentation. Thus, tapasin dependence level, like HLA zygosity, may serve as a means to restrict or expand breadth of the HLA-I peptide repertoire across humans, ultimately influencing immune responses to pathogens and vaccines.


Asunto(s)
Presentación de Antígeno/genética , Infecciones por VIH , Antígenos de Histocompatibilidad Clase I , Proteínas de Transporte de Membrana , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Proteínas del Virus de la Inmunodeficiencia Humana/inmunología , Humanos , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/inmunología , Proteínas de Transporte de Membrana/metabolismo , Péptidos/inmunología , Péptidos/metabolismo , Linfocitos T Citotóxicos/inmunología , Carga Viral/genética , Carga Viral/inmunología
11.
Genes Immun ; 22(7-8): 327-334, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34864821

RESUMEN

Human immunoglobulin G (IgG) molecules, IgG1, IgG2 and IgG3, exhibit substantial inter-individual variation in their constant heavy chain regions, as discovered by serological methods. This polymorphism is encoded by the IGHG1, IGHG2, and IGHG3 genes and may influence antibody function. We sequenced the coding fragments of these genes in 95 European Americans, 94 African Americans, and 94 Black South Africans. Striking differences were observed between the population groups, including extremely low amino acid sequence variation in IGHG1 among South Africans, and higher IGHG2 and IGHG3 diversity in individuals of African descent compared to individuals of European descent. Molecular definition of the loci illustrates a greater level of allelic polymorphism than previously described, including the presence of common IGHG2 and IGHG3 variants that were indistinguishable serologically. Comparison of our data with the 1000 Genome Project sequences indicates overall agreement between the datasets, although some inaccuracies in the 1000 Genomes Project are likely. These data represent the most comprehensive analysis of IGHG polymorphisms across major populations, which can now be applied to deciphering their functional impact.


Asunto(s)
Inmunoglobulina G , Cadenas Pesadas de Inmunoglobulina , Alelos , Genes de Inmunoglobulinas , Humanos , Inmunoglobulina G/genética , Cadenas Pesadas de Inmunoglobulina/genética , Polimorfismo Genético
12.
PLoS Pathog ; 15(12): e1008064, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31841557

RESUMEN

Broadly neutralizing antibodies (bNAbs) protect against HIV infection in non-human primates and their efficacy may be enhanced through interaction with Fc receptors on immune cells. Antibody isotype is a modulator of this binding with the IgG3 subclass mediating potent Fc effector function and is associated with HIV vaccine efficacy and HIV control. BNAb functions are typically assessed independently of the constant region with which they are naturally expressed. To examine the role of natural isotype in the context of a bNAb lineage we studied CAP256, an HIV-infected individual that mounted a potent V2-specific bNAb response. CAP256 expressed persistently high levels of plasma IgG3 which we found mediated both broad neutralizing activity and potent Fc function. Sequencing of germline DNA and the constant regions of V2-directed bNAbs from this donor revealed the expression of a novel IGHG3 allele as well as IGHG3*17, an allele that produces IgG3 antibodies with increased plasma half-life. Both allelic variants were used to generate CAP256-VRC26.25 and CAP256-VRC26.29 IgG3 bNAbs and these were compared to IgG1 versions. IgG3 variants were shown to have significantly higher phagocytosis and trogocytosis compared to IgG1 versions, which corresponded to increased affinity for FcγRIIa. Neutralization potency was also significantly higher for IgG3 bNAbs, particularly against viruses lacking the N160 glycan. By exchanging hinge regions between subclass variants, we showed that hinge length modulated both neutralization potency and Fc function. This study showed that co-operation between the variable and natural IgG3 constant regions enhanced the polyfunctionality of antibodies, indicating the value of leveraging genetic variation which could be exploited for passive immunity.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Inmunoglobulina G/inmunología , Isotipos de Inmunoglobulinas/inmunología , Adulto , Femenino , Infecciones por VIH/inmunología , Humanos , Receptores Fc/inmunología
13.
Proc Natl Acad Sci U S A ; 112(47): 14658-63, 2015 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-26553974

RESUMEN

Previous genome-wide association studies (GWAS) of HIV-1-infected populations have been underpowered to detect common variants with moderate impact on disease outcome and have not assessed the phenotypic variance explained by genome-wide additive effects. By combining the majority of available genome-wide genotyping data in HIV-infected populations, we tested for association between ∼8 million variants and viral load (HIV RNA copies per milliliter of plasma) in 6,315 individuals of European ancestry. The strongest signal of association was observed in the HLA class I region that was fully explained by independent effects mapping to five variable amino acid positions in the peptide binding grooves of the HLA-B and HLA-A proteins. We observed a second genome-wide significant association signal in the chemokine (C-C motif) receptor (CCR) gene cluster on chromosome 3. Conditional analysis showed that this signal could not be fully attributed to the known protective CCR5Δ32 allele and the risk P1 haplotype, suggesting further causal variants in this region. Heritability analysis demonstrated that common human genetic variation-mostly in the HLA and CCR5 regions-explains 25% of the variability in viral load. This study suggests that analyses in non-European populations and of variant classes not assessed by GWAS should be priorities for the field going forward.


Asunto(s)
Predisposición Genética a la Enfermedad , VIH-1/genética , Interacciones Huésped-Patógeno/genética , Polimorfismo de Nucleótido Simple/genética , Carga Viral/genética , Adulto , Alelos , Aminoácidos/genética , Cromosomas Humanos Par 3/genética , Estudio de Asociación del Genoma Completo , Antígenos HLA-B/genética , Humanos , Patrón de Herencia/genética , Mapeo Físico de Cromosoma , Receptores CCR5/genética
14.
PLoS Genet ; 10(3): e1004196, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24603468

RESUMEN

Natural progression of HIV-1 infection depends on genetic variation in the human major histocompatibility complex (MHC) class I locus, and the CD8+ T cell response is thought to be a primary mechanism of this effect. However, polymorphism within the MHC may also alter innate immune activity against human immunodeficiency virus type 1 (HIV-1) by changing interactions of human leukocyte antigen (HLA) class I molecules with leukocyte immunoglobulin-like receptors (LILR), a group of immunoregulatory receptors mainly expressed on myelomonocytic cells including dendritic cells (DCs). We used previously characterized HLA allotype-specific binding capacities of LILRB1 and LILRB2 as well as data from a large cohort of HIV-1-infected individuals (N = 5126) to test whether LILR-HLA class I interactions influence viral load in HIV-1 infection. Our analyses in persons of European descent, the largest ethnic group examined, show that the effect of HLA-B alleles on HIV-1 control correlates with the binding strength between corresponding HLA-B allotypes and LILRB2 (p = 10(-2)). Moreover, overall binding strength of LILRB2 to classical HLA class I allotypes, defined by the HLA-A/B/C genotypes in each patient, positively associates with viral replication in the absence of therapy in patients of both European (p = 10(-11)-10(-9)) and African (p = 10(-5)-10(-3)) descent. This effect appears to be driven by variations in LILRB2 binding affinities to HLA-B and is independent of individual class I allelic effects that are not related to the LILRB2 function. Correspondingly, in vitro experiments suggest that strong LILRB2-HLA binding negatively affects antigen-presenting properties of DCs. Thus, we propose an impact of LILRB2 on HIV-1 disease outcomes through altered regulation of DCs by LILRB2-HLA engagement.


Asunto(s)
Infecciones por VIH/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunidad Innata/genética , Glicoproteínas de Membrana/genética , Receptores Inmunológicos/genética , Alelos , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Femenino , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , VIH-1/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Glicoproteínas de Membrana/inmunología , Receptores Inmunológicos/inmunología , Carga Viral/genética , Carga Viral/inmunología
15.
J Virol ; 89(20): 10176-89, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26223643

RESUMEN

UNLABELLED: The pharmaceutical reactivation of dormant HIV-1 proviruses by histone deacetylase inhibitors (HDACi) represents a possible strategy to reduce the reservoir of HIV-1-infected cells in individuals treated with suppressive combination antiretroviral therapy (cART). However, the effects of such latency-reversing agents on the viral reservoir size are likely to be influenced by host immune responses. Here, we analyzed the immune factors associated with changes in proviral HIV-1 DNA levels during treatment with the potent HDACi panobinostat in a human clinical trial involving 15 cART-treated HIV-1-infected patients. We observed that the magnitude, breadth, and cytokine secretion profile of HIV-1-specific CD8 T cell responses were unrelated to changes in HIV-1 DNA levels in CD4 T cells during panobinostat treatment. In contrast, the proportions of CD3(-) CD56(+) total NK cells and CD16(+) CD56(dim) NK cells were inversely correlated with HIV-1 DNA levels throughout the study, and changes in HIV-1 DNA levels during panobinostat treatment were negatively associated with the corresponding changes in CD69(+) NK cells. Decreasing levels of HIV-1 DNA during latency-reversing treatment were also related to the proportions of plasmacytoid dendritic cells, to distinct expression patterns of interferon-stimulated genes, and to the expression of the IL28B CC genotype. Together, these data suggest that innate immune activity can critically modulate the effects of latency-reversing agents on the viral reservoir and may represent a target for future immunotherapeutic interventions in HIV-1 eradication studies. IMPORTANCE: Currently available antiretroviral drugs are highly effective in suppressing HIV-1 replication, but the virus persists, despite treatment, in a latent form that does not actively express HIV-1 gene products. One approach to eliminate these cells, colloquially termed the "shock-and-kill" strategy, focuses on the use of latency-reversing agents that induce active viral gene expression in latently infected cells, followed by immune-mediated killing. Panobinostat, a histone deacetylase inhibitor, demonstrated potent activities in reversing HIV-1 latency in a recent pilot clinical trial and reduced HIV-1 DNA levels in a subset of patients. Interestingly, we found that innate immune factors, such as natural killer cells, plasmacytoid dendritic cells, and the expression patterns of interferon-stimulated genes, were most closely linked to a decline in the HIV-1 DNA level during treatment with panobinostat. These data suggest that innate immune activity may play an important role in reducing the residual reservoir of HIV-1-infected cells.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , ADN Viral/antagonistas & inhibidores , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Inhibidores de Histona Desacetilasas/uso terapéutico , Ácidos Hidroxámicos/uso terapéutico , Inmunidad Innata/efectos de los fármacos , Indoles/uso terapéutico , Antígenos CD/genética , Antígenos CD/inmunología , Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/enzimología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/enzimología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Recuento de Células , ADN Viral/genética , ADN Viral/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/enzimología , Células Dendríticas/inmunología , Células Dendríticas/virología , Esquema de Medicación , Expresión Génica , Genotipo , Infecciones por VIH/enzimología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/crecimiento & desarrollo , VIH-1/inmunología , Histona Desacetilasas/genética , Histona Desacetilasas/inmunología , Humanos , Interferones , Interleucinas/genética , Interleucinas/inmunología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/enzimología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/virología , Panobinostat , Latencia del Virus/efectos de los fármacos
16.
J Infect Dis ; 210(7): 1047-51, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24719475

RESUMEN

A recent genome-wide association study (GWAS) involving patients with hemophilia A who were exposed to but uninfected with human immunodeficiency virus type 1 (HIV-1) did not reveal genetic variants associated with resistance to HIV-1 infection, beyond homozygosity for CCR5-Δ32. Since variation in HLA class I and KIR genes is not well interrogated by standard GWAS techniques, we tested whether these 2 loci were involved in protection from HIV-1 infection in the same hemophilia cohort, using controls from the general population. Our data indicate that HLA class I alleles, presence or absence of KIR genes, and functionally relevant combinations of the HLA/KIR genotypes are not involved in resistance to parenterally transmitted HIV-1 infection.


Asunto(s)
Resistencia a la Enfermedad , Infecciones por VIH/inmunología , Hemofilia A/complicaciones , Antígenos de Histocompatibilidad Clase I/inmunología , Receptores KIR/inmunología , Estudios de Asociación Genética , Humanos
17.
Immunogenetics ; 66(1): 1-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24096970

RESUMEN

Leukocyte immunoglobulin-like receptor (LILR)B3 and LILRA6 represent a pair of inhibitory/activating receptors with identical extracellular domains and unknown ligands. LILRB3 can mediate inhibitory signaling via immunoreceptor tyrosine-based inhibition motifs in its cytoplasmic tail whereas LILRA6 can signal through association with an activating adaptor molecule, FcRγ, which bears a cytoplasmic tail with an immunoreceptor tyrosine-based activation motif. The receptors are encoded by two highly polymorphic neighboring genes within the leukocyte receptor complex on human chromosome 19. Here, we report that the two genes display similar levels of single nucleotide polymorphisms with the majority of polymorphic sites being identical. In addition, the LILRA6 gene exhibits copy number variation (CNV) whereas LILRB3 does not. A screen of healthy Caucasians indicated that 32 % of the subjects possessed more than two copies of LILRA6, whereas 4 % have only one copy of the gene per diploid genome. Analysis of mRNA expression in the major fractions of PBMCs showed that LILRA6 is primarily expressed in monocytes, similarly to LILRB3, and its expression level correlates with copy number of the gene. We suggest that the LILRA6 CNV may influence the level of the activating receptor on the cell surface, potentially affecting signaling upon LILRB3/A6 ligation.


Asunto(s)
Antígenos CD/genética , Variaciones en el Número de Copia de ADN/genética , Polimorfismo de Nucleótido Simple/genética , Receptores Inmunológicos/genética , Niño , Estudios de Cohortes , ADN/análisis , ADN/genética , Familia , Femenino , Humanos , Masculino , Linaje , ARN Mensajero/genética
18.
Science ; 383(6680): 319-325, 2024 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-38236978

RESUMEN

Heterozygosity of Human leukocyte antigen (HLA) class I genes is linked to beneficial outcomes after HIV infection, presumably through greater breadth of HIV epitope presentation and cytotoxic T cell response. Distinct allotype pairs, however, differ in the extent to which they bind shared sets of peptides. We developed a functional divergence metric that measures pairwise complementarity of allotype-associated peptide binding profiles. Greater functional divergence for pairs of HLA-A and/or HLA-B allotypes was associated with slower AIDS progression and independently with enhanced viral load control. The metric predicts immune breadth at the peptide level rather than gene level and redefines HLA heterozygosity as a continuum differentially affecting disease outcome. Functional divergence may affect response to additional infections, vaccination, immunotherapy, and other diseases where HLA heterozygote advantage occurs.


Asunto(s)
Infecciones por VIH , Antígenos HLA-B , Heterocigoto , Humanos , Alelos , Progresión de la Enfermedad , Infecciones por VIH/genética , Infecciones por VIH/patología , Antígenos HLA-B/genética , Péptidos/genética , Péptidos/inmunología , Masculino , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano
19.
Structure ; 32(8): 1121-1136.e5, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38733995

RESUMEN

Immunogenetic studies have shown that specific HLA-B residues (67, 70, 97, and 156) mediate the impact of HLA class I on HIV infection, but the molecular basis is not well understood. Here we evaluate the function of these residues within the protective HLA-B∗5701 allele. While mutation of Met67, Ser70, and Leu156 disrupt CD8+ T cell recognition, substitution of Val97 had no significant impact. Thermal denaturation of HLA-B∗5701-peptide complexes revealed that Met67 and Leu156 maintain HLA-peptide stability, while Ser70 and Leu156 facilitate T cell receptor (TCR) interactions. Analyses of existing structures and structural models suggested that Val97 mediates HLA-peptide binding to inhibitory KIR3DL1 molecules, which was confirmed by experimental assays. These data thereby demonstrate that the genetic basis by which host immunity impacts HIV outcomes occurs by modulating HLA-B-peptide stability and conformation for interaction with TCR and killer immunoglobulin receptor (KIR) molecules. Moreover, they indicate a key role for epitope specificity and HLA-KIR interactions to HIV control.


Asunto(s)
Antígenos HLA-B , Unión Proteica , Receptores de Antígenos de Linfocitos T , Humanos , Antígenos HLA-B/química , Antígenos HLA-B/metabolismo , Antígenos HLA-B/genética , Antígenos HLA-B/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/inmunología , VIH-1/inmunología , VIH-1/metabolismo , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Modelos Moleculares , Receptores KIR3DL1/metabolismo , Receptores KIR3DL1/química , Receptores KIR3DL1/genética , Péptidos/química , Péptidos/metabolismo , Sitios de Unión , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Polimorfismo Genético , Estabilidad Proteica
20.
Nat Med ; 11(12): 1290-2, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16288280

RESUMEN

An effective acquired immune response to infectious agents mediated by HLA-restricted T-cell recognition can target different stages of disease pathogenesis. We show here that three distinct HLA alleles known to alter the overall rate of AIDS progression act during distinct intervals after HIV-1 infection. The discrete timing of HLA allele influence suggests alternative functional mechanisms in immune defense against this dynamic and chronic immunosuppressive disease.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Alelos , Linfocitos T CD8-positivos/inmunología , VIH-1/inmunología , Antígenos HLA-B/genética , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Progresión de la Enfermedad , Humanos , Análisis de Supervivencia , Factores de Tiempo
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