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1.
Anal Bioanal Chem ; 411(23): 6111-6118, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31367804

RESUMO

Application of a protease inhibitor, 4-(2-aminoethyl) benzenesulfonyl fluoride (AEBSF), during the cell culture process was demonstrated to effectively reduce proteolytic activity at a specific amino acid site during the production of an HIV-1 broadly neutralizing antibody (bNAb). However, the addition of AEBSF could potentially introduce some modifications to the bNAb protein. Experimental design from sample preparation to LC-MS characterization was performed using middle-up and bottom-up approaches to identify AEBSF-modified species for the bNAb using an AEBSF supplementation in the cell culture media. Modified species along with the unmodified control sample were also subjected to binding activity assessment. The results showed that two amino acids (Tyr177 and Lys250) were susceptible to AEBSF modification in the bNAb test articles but at a negligible level and not in the CDR regions, which therefore did not reduce the in vitro binding activity of the bNAb.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Imunoconjugados/imunologia , Inibidores de Proteases/imunologia , Sulfonas/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/química , Anticorpos Anti-HIV/química , Infecções por HIV/virologia , Humanos , Imunoconjugados/química , Inibidores de Proteases/química , Sulfonas/química , Espectrometria de Massas em Tandem
2.
Nat Commun ; 10(1): 3017, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289267

RESUMO

Differences among hosts, resulting from genetic variation in the immune system or heterogeneity in drug treatment, can impact within-host pathogen evolution. Genetic association studies can potentially identify such interactions. However, extensive and correlated genetic population structure in hosts and pathogens presents a substantial risk of confounding analyses. Moreover, the multiple testing burden of interaction scanning can potentially limit power. We present a Bayesian approach for detecting host influences on pathogen evolution that exploits vast existing data sets of pathogen diversity to improve power and control for stratification. The approach models key processes, including recombination and selection, and identifies regions of the pathogen genome affected by host factors. Our simulations and empirical analysis of drug-induced selection on the HIV-1 genome show that the method recovers known associations and has superior precision-recall characteristics compared to other approaches. We build a high-resolution map of HLA-induced selection in the HIV-1 genome, identifying novel epitope-allele combinations.


Assuntos
Evolução Molecular , HIV-1/genética , Antígenos HLA/imunologia , Interações Hospedeiro-Patógeno/genética , Modelos Genéticos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Teorema de Bayes , Conjuntos de Dados como Assunto , Epitopos/efeitos dos fármacos , Epitopos/genética , Epitopos/imunologia , Genoma Viral/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Recombinação Genética/efeitos dos fármacos , Recombinação Genética/imunologia , Seleção Genética/efeitos dos fármacos , Seleção Genética/imunologia
3.
Nat Commun ; 10(1): 2753, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266936

RESUMO

Elimination of HIV-1 requires clearance and removal of integrated proviral DNA from infected cells and tissues. Here, sequential long-acting slow-effective release antiviral therapy (LASER ART) and CRISPR-Cas9 demonstrate viral clearance in latent infectious reservoirs in HIV-1 infected humanized mice. HIV-1 subgenomic DNA fragments, spanning the long terminal repeats and the Gag gene, are excised in vivo, resulting in elimination of integrated proviral DNA; virus is not detected in blood, lymphoid tissue, bone marrow and brain by nested and digital-droplet PCR as well as RNAscope tests. No CRISPR-Cas9 mediated off-target effects are detected. Adoptive transfer of human immunocytes from dual treated, virus-free animals to uninfected humanized mice fails to produce infectious progeny virus. In contrast, HIV-1 is readily detected following sole LASER ART or CRISPR-Cas9 treatment. These data provide proof-of-concept that permanent viral elimination is possible.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Sistemas CRISPR-Cas , Infecções por HIV/terapia , HIV-1/genética , Transferência Adotiva , Animais , Terapia Combinada , DNA Viral/genética , DNA Viral/imunologia , Edição de Genes , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/fisiologia , Humanos , Camundongos , Resultado do Tratamento , Latência Viral
4.
Nat Commun ; 10(1): 2898, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263112

RESUMO

The HIV-1 envelope (Env) is the target for neutralizing antibodies and exists on the surface of virions in open or closed conformations. Difficult-to-neutralize viruses (tier 2) express Env in a closed conformation antigenic for broadly neutralizing antibodies (bnAbs) but not for third variable region (V3) antibodies. Here we show that select V3 macaque antibodies elicited by Env vaccination can neutralize 26% of otherwise tier 2 HIV-1 isolates in standardized virus panels. The V3 antibodies only bound to Env in its open conformation. Thus, Envs on tier 2 viruses sample a state where the V3 loop is not in its closed conformation position. Envelope second variable region length, glycosylation sites and V3 amino acids were signatures of neutralization sensitivity. This study determined that open conformations of Env with V3 exposed are present on a subset of otherwise neutralization-resistant virions, therefore neutralization of tier 2 HIV-1 does not always indicate bnAb induction.


Assuntos
Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Motivos de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Glicosilação , Infecções por HIV/virologia , HIV-1/química , HIV-1/genética , Humanos , Macaca mulatta , Testes de Neutralização , Conformação Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/química
5.
Nat Commun ; 10(1): 2759, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227717

RESUMO

Langerhans cells (LC) are thought to be the only mononuclear phagocyte population in the epidermis where they detect pathogens. Here, we show that CD11c+ dendritic cells (DCs) are also present. These cells are transcriptionally similar to dermal cDC2 but are more efficient antigen-presenting cells. Compared to LCs, epidermal CD11c+ DCs are enriched in anogenital tissues where they preferentially interact with HIV, express the higher levels of HIV entry receptor CCR5, support the higher levels of HIV uptake and replication and are more efficient at transmitting the virus to CD4 T cells. Importantly, these findings are observed using both a lab-adapted and transmitted/founder strain of HIV. We also describe a CD33low cell population, which is transcriptionally similar to LCs but does not appear to function as antigen-presenting cells or acts as HIV target cells. Our findings reveal that epidermal DCs in anogenital tissues potentially play a key role in sexual transmission of HIV.


Assuntos
Células Dendríticas/virologia , Células Epidérmicas/virologia , Infecções por HIV/transmissão , HIV-1/imunologia , Apresentação do Antígeno/imunologia , Antígeno CD11c/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Epidérmicas/imunologia , Células Epidérmicas/metabolismo , Epiderme/imunologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Voluntários Saudáveis , Humanos , Masculino , Cultura Primária de Células , Receptores CCR5/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Linfócitos T/imunologia , Internalização do Vírus
6.
BMC Infect Dis ; 19(1): 518, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195994

RESUMO

BACKGROUND: Heterosexual transmission is the main driver of the HIV epidemic in Tanzania. Only one estimate of the incidence rate of intra-marital HIV seroconversion in Tanzania has been reported and was derived from data collected between 1991 and 1995. Moreover, little is known about the specific risk factors for intra-marital seroconversion in Tanzania. Improved evidence around factors that increase the risk of HIV transmission to a serodiscordant spouse is needed to develop and improve evidence-based interventions. We sought to investigate the rate of intra-marital HIV seroconversion among HIV sero-discordant couples in Tanzania as well as its associated risk factors. METHODS: We identified all HIV positive individuals in the TAZAMA HIV-serosurvey cohort and followed up their serodiscordant spouse from 2006 to 2016. The rate of seroconversion was analyzed by survival analysis using non-parametric regressions with exponential distribution. RESULTS: We found 105 serodiscordant couples, 14 of which had a seroconverting spouse. The overall HIV-1 incidence rate among spouses of people with HIV-1 infection was 38.0 per 1000 person/years [22.5-64.1]. Notably, the HIV-1 incidence rate among HIV-1 seronegative male spouses was 6.7[0.9-47.5] per 1000 person/years, compared to 59.3 [34.4-102.1] per 1000 person/years among female spouses. Sex of the serodiscordant spouse was the only significant variable, even after adjusting for other variables (Hazard rate = 8.86[1.16-67.70], p = 0.036). CONCLUSIONS: Our study suggests that rates of HIV-1 seroconversion of sero-discordant partners are much higher within marriage than in the general population in Tanzania. The major risk factor for HIV-1 seroconversion is sex of the serodiscordant spouse, with female spouses being at very high risk of acquiring HIV infection. This suggests that future programs that target serodiscordant couples could be a novel and effective means of preventing HIV-1 transmission in Tanzania.


Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , Adulto , Estudos de Coortes , Teste em Amostras de Sangue Seco , Feminino , Seguimentos , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/imunologia , HIV-1/isolamento & purificação , Heterossexualidade , Humanos , Incidência , Masculino , Modelos de Riscos Proporcionais , Fatores de Risco , Cônjuges , Tanzânia/epidemiologia
7.
Nat Commun ; 10(1): 2190, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31097697

RESUMO

HIV-infected infants develop broadly neutralizing plasma responses with more rapid kinetics than adults, suggesting the ontogeny of infant responses could better inform a path to achievable vaccine targets. Here we reconstruct the developmental lineage of BF520.1, an infant-derived HIV-specific broadly neutralizing antibody (bnAb), using computational methods developed specifically for this purpose. We find that the BF520.1 inferred naive precursor binds HIV Env. We also show that heterologous cross-clade neutralizing activity evolved in the infant within six months of infection and that, ultimately, only 2% SHM is needed to achieve the full breadth of the mature antibody. Mutagenesis and structural analyses reveal that, for this infant bnAb, substitutions in the kappa chain were critical for activity, particularly in CDRL1. Overall, the developmental pathway of this infant antibody includes features distinct from adult antibodies, including several that may be amenable to better vaccine responses.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Cadeias kappa de Imunoglobulina/imunologia , Vacinas contra a AIDS/imunologia , Fatores Etários , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Neutralizantes/metabolismo , Biologia Computacional/métodos , Reações Cruzadas/imunologia , Desenho de Drogas , Anticorpos Anti-HIV/genética , Anticorpos Anti-HIV/isolamento & purificação , Anticorpos Anti-HIV/metabolismo , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Cadeias kappa de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/metabolismo , Lactente , Leucócitos Mononucleares , Mutagênese , Análise de Sequência de DNA , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
8.
Science ; 364(6439): 480-484, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31048489

RESUMO

Mutationally constrained epitopes of variable pathogens represent promising targets for vaccine design but are not reliably identified by sequence conservation. In this study, we employed structure-based network analysis, which applies network theory to HIV protein structure data to quantitate the topological importance of individual amino acid residues. Mutation of residues at important network positions disproportionately impaired viral replication and occurred with high frequency in epitopes presented by protective human leukocyte antigen (HLA) class I alleles. Moreover, CD8+ T cell targeting of highly networked epitopes distinguished individuals who naturally control HIV, even in the absence of protective HLA alleles. This approach thereby provides a mechanistic basis for immune control and a means to identify CD8+ T cell epitopes of topological importance for rational immunogen design, including a T cell-based HIV vaccine.


Assuntos
Vacinas contra a AIDS/genética , Vacinas contra a AIDS/imunologia , Síndrome de Imunodeficiência Adquirida/prevenção & controle , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , HIV-1/imunologia , Alelos , Sequência Conservada , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Mutação , Proteoma/genética , Proteoma/imunologia , Replicação Viral , Produtos do Gene gag do Vírus da Imunodeficiência Humana
9.
Arch Virol ; 164(8): 2083-2090, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31134354

RESUMO

Although a few studies have been done on transmissible blood-borne viral infections in high-risk groups, little attention has been given to assessing the infection status of the general population in Afghanistan. To investigate the epidemiological status in the general population, we tested the serological markers of hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis delta virus (HDV), human immunodeficiency virus 1 (HIV-1) and human T-cell leukemia virus (HTLV) infections. In total, 492 samples were selected randomly from Nangarhar, Herat, Mazar-e Sharif, Kandahar, and Kabul from subjects between 25 and 70 years old. The samples were tested for the presence of HBsAg, anti-HBs, anti-HBc, anti-HDV, anti-HCV, anti-HIV-1 and anti-HTLV I/II antibodies using chemiluminescent immunoassays on Abbott Architect automated platforms. In addition, 220 HBsAg-positive samples identified among 5897 samples from the general population of the same regions of Afghanistan were included in the study and tested for both HBsAg and anti-HDV to investigate HDV prevalence in the country. Viral loads of HBV, HCV and HDV were determined in all seropositive samples using Ampliprep/Cobas TaqMan HBV, HCV, Test Roche (CA, USA), and an in-house method, respectively. Out of 492 samples, 31 (6.3%), 136 (27.6%) and 149 (30.3%) were found to be positive for HBsAg, anti-HBs and anti-HBc, respectively. Anti-HDV positivity was detected in five (2.1%) out of 234 HBsAg-positive samples (including 14 of the randomly selected samples that were not among the 220 previously identified as HBsAg positive). Only eight out of 492 (1.6%) subjects were positive for anti-HCV antibodies. Seven out of 489 (1.4%) were positive for anti-HIV-1 antibodies, and three out of 466 cases (0.6%) were positive for anti-HTLV I/II antibodies. These results suggest that Afghanistan is an intermediate endemic region for HBV, HDV and HCV infection. The prevalence of HIV-1 seems to be significantly higher than the global prevalence and that of the eastern Mediterranean region. In addition, the HTLV I/II screening results suggest that these viruses should be monitored in Afghanistan to confirm the trend observed in the current study.


Assuntos
Viroses/epidemiologia , Adulto , Afeganistão/epidemiologia , DNA Viral/genética , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , HIV-1/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite/imunologia , Hepatite B/epidemiologia , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite C/epidemiologia , Hepatite C/imunologia , Anticorpos Anti-Hepatite C/imunologia , Hepatite D/epidemiologia , Hepatite D/imunologia , Vírus Delta da Hepatite/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Carga Viral/métodos , Viroses/imunologia
11.
Nat Commun ; 10(1): 2355, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142746

RESUMO

Stabilized HIV-1 envelope glycoproteins (Env) that resemble the native Env are utilized in vaccination strategies aimed at inducing broadly neutralizing antibodies (bNAbs). To limit the exposure of rare isolate-specific antigenic residues/determinants we generated a SOSIP trimer based on a consensus sequence of all HIV-1 group M isolates (ConM). The ConM trimer displays the epitopes of most known bNAbs and several germline bNAb precursors. The crystal structure of the ConM trimer at 3.9 Å resolution resembles that of the native Env trimer and its antigenic surface displays few rare residues. The ConM trimer elicits strong NAb responses against the autologous virus in rabbits and macaques that are significantly enhanced when it is presented on ferritin nanoparticles. The dominant NAb specificity is directed against an epitope at or close to the trimer apex. Immunogens based on consensus sequences might have utility in engineering vaccines against HIV-1 and other viruses.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Sequência Consenso , Macaca , Multimerização Proteica , Coelhos
13.
Appl Microbiol Biotechnol ; 103(13): 5183-5192, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31020381

RESUMO

Recombinant Saccharomyces cerevisiae strains expressing HIV antigens have shown promising pre-clinical results. Probiotic S. cerevisiae strains naturally induce gut immunity; thus, genetically engineered probiotic strains could be used to stimulate immune responses against HIV in the mucosa. Probiotic strains have a higher rate of heterologous protein production, meaning higher antigen's epitope expression levels per yeast cell. We expressed HIV-1 Gag protein in the probiotic yeasts' surface, which was eagerly phagocytosed by and induced type 1 polarization of human monocyte-derived dendritic cells (DCs) from healthy donors in vitro. We further matured DCs derived from HIV-1+ donors with transformed yeasts and incubated them with autologous T cells. Only DCs matured with Gag-expressing probiotic strains were able to efficiently present antigen to CD8+ T cells and induced their clonal expansion. Our results show that genetically engineered probiotic S. cerevisiae strains are a promising vaccination strategy against HIV.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Memória Imunológica , Probióticos , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/imunologia , Apresentação do Antígeno , Diferenciação Celular , Engenharia Genética , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Fagocitose , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/imunologia , Células Th1/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
14.
Nat Med ; 25(4): 547-553, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30936546

RESUMO

Combination anti-retroviral therapy (ART) has revolutionized the treatment and prevention of HIV-1 infection. Taken daily, ART prevents and suppresses the infection. However, ART interruption almost invariably leads to rebound viremia in infected individuals due to a long-lived latent reservoir of integrated proviruses. Therefore, ART must be administered on a life-long basis. Here we review recent preclinical and clinical studies suggesting that immunotherapy may be an alternative or an adjuvant to ART because, in addition to preventing new infections, anti-HIV-1 antibodies clear the virus, directly kill infected cells and produce immune complexes that can enhance host immunity to the virus.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/imunologia , Animais , Ensaios Clínicos como Assunto , Infecções por HIV/prevenção & controle , Humanos
16.
PLoS Comput Biol ; 15(4): e1006954, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30970017

RESUMO

HIV is a highly mutable virus for which all attempts to develop a vaccine have been unsuccessful. Nevertheless, few long-infected patients develop antibodies, called broadly neutralizing antibodies (bnAbs), that have a high breadth and can neutralize multiple variants of the virus. This suggests that a universal HIV vaccine should be possible. A measure of the efficacy of a HIV vaccine is the neutralization breadth of the antibodies it generates. The breadth is defined as the fraction of viruses in the Seaman panel that are neutralized by the antibody. Experimentally the neutralization ability is measured as the half maximal inhibitory concentration of the antibody (IC50). To avoid such time-consuming experimental measurements, we developed a computational approach to estimate the IC50 and use it to determine the antibody breadth. Given that no direct method exists for calculating IC50 values, we resort to a combination of atomistic modeling and machine learning. For each antibody/virus complex, an all-atoms model is built using the amino acid sequence and a known structure of a related complex. Then a series of descriptors are derived from the atomistic models, and these are used to train a Multi-Layer Perceptron (an Artificial Neural Network) to predict the value of the IC50 (by regression), or if the antibody binds or not to the virus (by classification). The neural networks are trained by use of experimental IC50 values collected in the CATNAP database. The computed breadths obtained by regression and classification are reported and the importance of having some related information in the data set for obtaining accurate predictions is analyzed. This approach is expected to prove useful for the design of HIV bnAbs, where the computation of the potency must be accompanied by a computation of the breadth, and for evaluating the efficiency of potential vaccination schemes developed through modeling and simulation.


Assuntos
Biologia Computacional/métodos , Anticorpos Anti-HIV/classificação , Anticorpos Anti-HIV/imunologia , Vacinas contra a AIDS/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Antígenos CD4/imunologia , Contagem de Linfócito CD4/métodos , Epitopos/imunologia , Anticorpos Anti-HIV/genética , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Concentração Inibidora 50 , Aprendizado de Máquina
17.
PLoS Pathog ; 15(4): e1007672, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30973942

RESUMO

Gastrointestinal (GI) mucosal dysfunction predicts and likely contributes to non-infectious comorbidities and mortality in HIV infection and persists despite antiretroviral therapy. However, the mechanisms underlying this dysfunction remain incompletely understood. Neutrophils are important for containment of pathogens but can also contribute to tissue damage due to their release of reactive oxygen species and other potentially harmful effector molecules. Here we used a flow cytometry approach to investigate increased neutrophil lifespan as a mechanism for GI neutrophil accumulation in chronic, treated HIV infection and a potential role for gastrointestinal dysbiosis. We report that increased neutrophil survival contributes to neutrophil accumulation in colorectal biopsy tissue, thus implicating neutrophil lifespan as a new therapeutic target for mucosal inflammation in HIV infection. Additionally, we characterized the intestinal microbiome of colorectal biopsies using 16S rRNA sequencing. We found that a reduced Lactobacillus: Prevotella ratio associated with neutrophil survival, suggesting that intestinal bacteria may contribute to GI neutrophil accumulation in treated HIV infection. Finally, we provide evidence that Lactobacillus species uniquely decrease neutrophil survival and neutrophil frequency in vitro, which could have important therapeutic implications for reducing neutrophil-driven inflammation in HIV and other chronic inflammatory conditions.


Assuntos
Colo/imunologia , Microbioma Gastrointestinal/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Inflamação/imunologia , Neutrófilos/imunologia , Reto/imunologia , Colo/microbiologia , Colo/patologia , Feminino , Infecções por HIV/virologia , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Reto/microbiologia , Reto/patologia
18.
EBioMedicine ; 42: 109-119, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30956171

RESUMO

BACKGROUND: HIV-1-specific CD8+ T cells are required for immune suppression of HIV-1 replication and elimination of the associated viral reservoirs. However, effective induction of functional HIV-1-specific CD8+ T cells from naïve cells remains problematic in the setting of human vaccine trials. In this study, we investigated priming of functional HIV-1-specific CD8+ T cells from naïve cells. METHODS: HIV-1-specific CD8+ T cells were primed from naïve T cells of HIV-1-seronegative individuals using TLR4 ligand LPS or STING ligand 3'3'-cGAMP in vitro. We established HIV-1-specific CD8+ T cell lines from primed T cells and then investigated functional properties of these cells. FINDINGS: HIV-1-specific CD8+ T cells primed with LPS failed to suppress HIV-1. In contrast, 3'3'-cGAMP effectively primed HIV-1-specific CD8+ T cells with strong ability to suppress HIV-1. 3'3'-cGAMP-primed T cells had higher expression levels of perforin and granzyme B than LPS-primed ones. The expression levels of granzyme B and perforin and viral suppression ability of 3'3'-cGAMP-primed T cells were positively correlated with the production level of type I IFN from PBMCs stimulated with 3'3'-cGAMP. INTERPRETATION: The present study demonstrates the potential of 3'3'-cGAMP to induce HIV-1-specific CD8+ T cells with strong effector function from naïve cells via a strong type I IFN production and suggests that this STING ligand may be useful for AIDS vaccine and cure treatment.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Subpopulações de Linfócitos T/imunologia , Biomarcadores , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/imunologia , Citocinas/metabolismo , Humanos , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/metabolismo , Carga Viral , Replicação Viral
19.
PLoS Comput Biol ; 15(4): e1006952, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933973

RESUMO

The broadly neutralizing antibody (bnAb) VRC01 is being evaluated for its efficacy to prevent HIV-1 infection in the Antibody Mediated Prevention (AMP) trials. A secondary objective of AMP utilizes sieve analysis to investigate how VRC01 prevention efficacy (PE) varies with HIV-1 envelope (Env) amino acid (AA) sequence features. An exhaustive analysis that tests how PE depends on every AA feature with sufficient variation would have low statistical power. To design an adequately powered primary sieve analysis for AMP, we modeled VRC01 neutralization as a function of Env AA sequence features of 611 HIV-1 gp160 pseudoviruses from the CATNAP database, with objectives: (1) to develop models that best predict the neutralization readouts; and (2) to rank AA features by their predictive importance with classification and regression methods. The dataset was split in half, and machine learning algorithms were applied to each half, each analyzed separately using cross-validation and hold-out validation. We selected Super Learner, a nonparametric ensemble-based cross-validated learning method, for advancement to the primary sieve analysis. This method predicted the dichotomous resistance outcome of whether the IC50 neutralization titer of VRC01 for a given Env pseudovirus is right-censored (indicating resistance) with an average validated AUC of 0.868 across the two hold-out datasets. Quantitative log IC50 was predicted with an average validated R2 of 0.355. Features predicting neutralization sensitivity or resistance included 26 surface-accessible residues in the VRC01 and CD4 binding footprints, the length of gp120, the length of Env, the number of cysteines in gp120, the number of cysteines in Env, and 4 potential N-linked glycosylation sites; the top features will be advanced to the primary sieve analysis. This modeling framework may also inform the study of VRC01 in the treatment of HIV-infected persons.


Assuntos
Anticorpos Monoclonais/farmacologia , Proteína gp160 do Envelope de HIV/genética , Proteína gp160 do Envelope de HIV/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Antígenos CD4 , Simulação por Computador , Previsões/métodos , Glicosilação , Anticorpos Anti-HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Ligação Proteica
20.
Immunity ; 50(3): 677-691.e13, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30876875

RESUMO

Lineage-based vaccine design is an attractive approach for eliciting broadly neutralizing antibodies (bNAbs) against HIV-1. However, most bNAb lineages studied to date have features indicative of unusual recombination and/or development. From an individual in the prospective RV217 cohort, we identified three lineages of bNAbs targeting the membrane-proximal external region (MPER) of the HIV-1 envelope. Antibodies RV217-VRC42.01, -VRC43.01, and -VRC46.01 used distinct modes of recognition and neutralized 96%, 62%, and 30%, respectively, of a 208-strain virus panel. All three lineages had modest levels of somatic hypermutation and normal antibody-loop lengths and were initiated by the founder virus MPER. The broadest lineage, VRC42, was similar to the known bNAb 4E10. A multimeric immunogen based on the founder MPER activated B cells bearing the unmutated common ancestor of VRC42, with modest maturation of early VRC42 intermediates imparting neutralization breadth. These features suggest that VRC42 may be a promising template for lineage-based vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Vacinas contra a AIDS/imunologia , Sequência de Aminoácidos , Linfócitos B/imunologia , Linhagem Celular , Células HEK293 , Infecções por HIV/imunologia , Humanos , Leucócitos Mononucleares , Estudos Longitudinais
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