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1.
Results Probl Cell Differ ; 71: 319-328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37996684

RESUMO

HIV-1 cell-free infection has been thoroughly investigated; however, its relevance and importance in vitro are questionable. Cell-cell transmission is now thought to be the dominant mode of transmission within the host; however precise molecular details remain elusive. The considerable potency of cell-cell transmission hinges upon its ability to hijack and manipulate host immunological function to target uninfected cells, along with overcoming restriction factors and increasing the speed of latent pool formation. Another question of relevance is virus induced cell-cell fusion and how this process is regulated. How often HIV-1 induces the formation of syncytia? Is cell-cell function a potential process for HIV-1 transmission? These questions are discussed and reviewed together with a description of the most common ways of HIV-1 entry and transinfection.


Assuntos
HIV-1 , HIV-1/fisiologia , Fusão Celular , Células Gigantes/fisiologia
2.
Biochim Biophys Acta Biomembr ; 1866(1): 184235, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37793559

RESUMO

The fusion peptide (FP) and the Trp-rich membrane proximal external region (MPER) display membrane activity during HIV-1 fusion. These domains are highly conserved in the envelope glycoprotein (Env) and, consequently, antibodies targeting these regions block entry of divergent HIV strains and isolates into target cells. With the aim of recovering concurrent responses against the membrane-active Env domains, we have produced hybrid peptides that connect FP and MPER sequences via flexible aminohexanoic acid tethers, and tested their potential as immunogens. We demonstrate that liposome-based formulations containing FP-MPER hybrid peptides could elicit in rabbits, antibodies with the binding sequence specificity of neutralizing antibodies that engage with the N-terminal MPER sub-region. Determination of the thermodynamic parameters of binding using the Fab 2F5 as an N-terminal MPER antibody model, revealed that the hydrophobic interaction surface for epitope engagement appears to be optimal in the FP-MPER hybrid. In general, our data support: i) the use of liposomes as carriers for membrane active peptides; ii) the capacity of these liposome-based vaccines to focus humoral responses to N-terminal MPER epitopes; and iii) the need to include lipid membranes in immunogens to elicit such specific responses.


Assuntos
HIV-1 , Animais , Coelhos , HIV-1/metabolismo , Lipossomos/química , Produtos do Gene env , Proteína gp41 do Envelope de HIV/química , Peptídeos/química , Epitopos , Imunidade , Vacinas de Subunidades
3.
Front Immunol ; 14: 1270908, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045703

RESUMO

Introduction: The generation of an HIV-1 vaccine able to induce long-lasting protective immunity remains a main challenge. Here, we aimed to modify next-generation soluble, prefusion-stabilized, close-to-native, glycan-engineered clade C gp140 envelope (Env) trimers (sC23v4 KIKO and ConCv5 KIKO) for optimal display on the cell surface following homologous or heterologous vector delivery. Methods: A combination of the following modifications scored best regarding the preservation of closed, native-like Env trimer conformation and antigenicity when using a panel of selected broadly neutralizing (bnAb) and non-neutralizing (nnAb) monoclonal antibodies for flow cytometry: i) replacing the natural cleavage site with a native flexible linker and introducing a single amino acid substitution to prevent CD4 binding (*), ii) fusing a heterologous VSV-G-derived transmembrane moiety to the gp140 C-terminus, and iii) deleting six residues proximal to the membrane. Results: When delivering membrane-tethered sC23v4 KIKO* and ConCv5 KIKO* via DNA, VSV-GP, and NYVAC vectors, the two native-like Env trimers provide differential antigenicity profiles. Whereas such patterns were largely consistent among the different vectors for either Env trimer, the membrane-tethered ConCv5 KIKO* trimer adopted a more closed and native-like structure than sC23v4 KIKO*. In immunized mice, VSV-GP and NYVAC vectors expressing the membrane-tethered ConCv5 KIKO* administered in prime/boost combination were the most effective regimens for the priming of Env-specific CD4 T cells among all tested combinations. The subsequent booster administration of trimeric ConCv5 KIKO* Env protein preserved the T cell activation levels between groups. The evaluation of the HIV-1-specific humoral responses induced in the different immunization groups after protein boosts showed that the various prime/boost protocols elicited broad and potent antibody responses, preferentially of a Th1-associated IgG2a subclass, and that the obtained antibody levels remained high at the memory phase. Discussion: In summary, we provide a feasible strategy to display multiple copies of native-like Env trimers on the cell surface, which translates into efficient priming of sustained CD4+ T cell responses after vector delivery as well as broad, potent, and sustained antibody responses following booster immunizations with the homologous, prefusion-stabilized, close-to-native ConCv5 KIKO* gp140 Env trimer.


Assuntos
Vacinas contra a AIDS , Soropositividade para HIV , HIV-1 , Animais , Camundongos , Anticorpos Anti-HIV , HIV-1/genética , Proteínas de Membrana , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Anticorpos Neutralizantes , Vacinas contra a AIDS/genética , Imunidade
5.
Euro Surveill ; 28(48)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38037731

RESUMO

BackgroundThe global distribution of HIV-1 subtypes is evolving, which is reflected in the Swedish HIV cohort. The subtype HIV-1A6, which may be prone to developing resistance to cabotegravir, is the most common subtype in Ukraine.AimWe aimed to examine trends in HIV-1 subtype distribution in Sweden, with a special focus on HIV-1A6, and to describe the virology, demography and treatment of Ukrainian people living with HIV (PLWH) who migrated to Sweden in 2022.MethodsData about PLWH in Sweden are included in a national database (InfCareHIV). We used the online tool COMET to establish HIV-1 subtypes and the Stanford database to define drug resistance mutations. We investigated the relation between virological characteristics and demographic data.ResultsThe early epidemic was predominated by HIV-1 subtype B infections in people born in Sweden. After 1990, the majority of new PLWH in Sweden were PLWH migrating to Sweden, resulting in an increasingly diverse epidemic. In 2022, HIV-1A6 had become the sixth most common subtype in Sweden and 98 of the 431 new PLWH that were registered in Sweden came from Ukraine. We detected HIV RNA in plasma of 32 Ukrainian patients (34%), of whom 17 were previously undiagnosed, 10 had interrupted therapy and five were previously diagnosed but not treated. We found HIV-1A6 in 23 of 24 sequenced patients.ConclusionThe molecular HIV epidemiology in Sweden continues to diversify and PLWH unaware of their HIV status and predominance of HIV-1A6 should be considered when arranging care directed at PLWH from Ukraine.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , HIV-1/genética , Suécia/epidemiologia , Infecções por HIV/tratamento farmacológico , Ucrânia/epidemiologia , Epidemiologia Molecular
6.
Biol Pharm Bull ; 46(11): 1535-1547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37914356

RESUMO

The introduction of combined anti-retroviral therapy (cART) in 1996, along with a continual breakthrough in anti-human immunodeficiency virus-1 (HIV-1) drugs, has improved the life expectancies of HIV-1-infected individuals. However, the incidence of drug-resistant viruses between individuals undergoing cART and treatment-naïve individuals is a common challenge. Therefore, there is a requirement to explore potential drug targets by considering various stages of the viral life cycle. For instance, the late stage, or viral release stage, remains uninvestigated extensively in antiviral drug discovery. In this study, we prepared a natural plant library and selected candidate plant extracts that inhibited HIV-1 release based on our laboratory-established screening system. The plant extracts from Epilobium hirsutum L. and Chamerion angustifolium (L.) Holub, belonging to the family Onagraceae, decreased HIV-1 release and accelerated the apoptosis in HIV-1-infected T cells but not uninfected T cells. A flavonol glycoside quercetin with oenothein B in Onagraceae reduced HIV-1 release in HIV-1-infected T cells. Moreover, extracts from Chamerion angustifolium (L.) Holub and Senna alexandrina Mill. inhibited the infectivity of progeny viruses. Together, these results suggest that C. angustifolium (L.) Holub contains quercetin with oenothein B that synergistically blocks viral replication and kills infected cells via an apoptotic pathway. Consequently, the plant extracts from the plant library of Turkey might be suitable candidates for developing novel anti-retroviral drugs that target the late phase of the HIV-1 life cycle.


Assuntos
HIV-1 , Onagraceae , Humanos , Quercetina/farmacologia , Extratos Vegetais/farmacologia , Turquia , Apoptose
7.
Sci Rep ; 13(1): 18994, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923825

RESUMO

Natural killer (NK) cell subsets with adaptive properties are emerging as regulators of vaccine-induced T and B cell responses and are specialized towards antibody-dependent functions contributing to SARS-CoV-2 control. Although HIV-1 infection is known to affect the NK cell pool, the additional impact of SARS-CoV-2 infection and/or vaccination on NK cell responses in people living with HIV (PLWH) has remained unexplored. Our data show that SARS-CoV-2 infection skews NK cells towards a more differentiated/adaptive CD57+FcεRIγ- phenotype in PLWH. A similar subset was induced following vaccination in SARS-CoV-2 naïve PLWH in addition to a CD56bright population with cytotoxic potential. Antibody-dependent NK cell function showed robust and durable responses to Spike up to 148 days post-infection, with responses enriched in adaptive NK cells. NK cell responses were further boosted by the first vaccine dose in SARS-CoV-2 exposed individuals and peaked after the second dose in SARS-CoV-2 naïve PLWH. The presence of adaptive NK cells associated with the magnitude of cellular and humoral responses. These data suggest that features of adaptive NK cells can be effectively engaged to complement and boost vaccine-induced adaptive immunity in potentially more vulnerable groups such as PLWH.


Assuntos
COVID-19 , Infecções por HIV , HIV-1 , Vacinas , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Células Matadoras Naturais , Anticorpos , Infecções por HIV/complicações , Anticorpos Antivirais
8.
Front Immunol ; 14: 1267564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954593

RESUMO

Background: HIV infection induces a 75% increase in the risk of developing neurocognitive impairment (NCI), which has been linked to immune activation. We therefore looked for immune activation markers correlating with NCI. Method: Sixty-five people aged 55-70 years living with controlled HIV-1 infection were enrolled in the study and their neurocognitive ability was assessed according to the Frascati criteria. Fifty-nine markers of T4 cell, T8 cell, NK cell, and monocyte activation, inflammation and endothelial activation were measured in their peripheral blood. White matter hyperintensities (WMH) were identified by magnetic resonance imaging. Double hierarchical clustering was performed for the activation markers and 240 patients including the 65 whose neurocognitive performance had been evaluated. Results: Thirty-eight percent of volunteers presented NCI. Twenty-four percent of them were asymptomatic and fourteen percent had a mild disorder. Strikingly, activated (HLA-DR+) as well as senescent (CD57+CD28-CD27±) T4 cells and T8 cells were less prevalent in the peripheral blood of participants with NCI than in participants without the disorder. Accordingly, the percentage of HLA-DR+ T4 cells was lower in volunteers with periventricular and deep WMH. The double hierarchical clustering unveiled six different immune activation profiles. The neurocognitive performances of participants with two of these six profiles were poor. Here again, these two profiles were characterized by a low level of T4 and T8 cell activation and senescence. Conclusion: Our observation of low circulating levels of activated and senescent T cells in HIV-1 patients with NCI raises the interesting hypothesis that these lymphocytes may be recruited into the central nervous system.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Linfócitos T CD4-Positivos , Antígenos HLA-DR , Transtornos Neurocognitivos/complicações , Biomarcadores
9.
Front Cell Infect Microbiol ; 13: 1284815, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965253

RESUMO

Co-circulation of different human immunodeficiency virus type 1 HIV-1 subtypes among infected populations can lead to the generation of new recombinants. In Pakistan, subtype A1 and CRF02_AG are the dominant strains circulating among key populations. The high prevalence of new HIV infections among the key populations highlights the possibility of recombination between the dominant strains, which can lead to the generation of new recombinants. Here, we identified a recombinant cluster composed of CRF02_AG, sub-subtype A3, and subtype G among HIV-infected children in Larkana. For the study, 10 retrospectively collected samples, with recombination signals in the pol gene, were used to perform a near full-length genome NFLG sequencing. Of the 10 samples, NFLG was successfully sequenced from seven samples. Phylogenetic analysis of the seven NFLGs showed that all recombinants formed a distinct monophyletic cluster and were distinct from known HIV-1 circulating recombinant forms CRFs. Recombination analyses showed that all seven NFLGs shared a similar recombinant structure consisting of CRF02_AG, sub-subtype A3, and subtype G, with a sub-subtype A3 fragment inserted into pol and vif regions spanning from (HXB2: 4218-5518), and a subtype G fragment inserted into vpu, rev, tat and env regions spanning from (HXB2: 5957-8250) of the CRF02_AG backbone. The identification of unique recombinant forms may indicate the presence and transmission of several co-circulating lineages in Larkana, giving rise to newer CRFs. This study also highlights the importance of continuous molecular surveillance to fully understand HIV-1 genetic diversity in Pakistan, particularly in Larkana, which is the epicenter of HIV outbreaks.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Criança , Infecções por HIV/epidemiologia , HIV-1/genética , Estudos Retrospectivos , Filogenia , Paquistão/epidemiologia , Recombinação Genética , Genótipo
10.
Front Immunol ; 14: 1249133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965312

RESUMO

Human Immunodeficiency Virus (HIV-1) is known to establish a persistent latent infection. The use of combination antiretroviral therapy (cART) can effectively reduce the viral load, but the treatment can be costly and may lead to the development of drug resistance and life-shortening side effects. It is important to develop an ideal and safer in vivo target therapy that will effectively block viral replication and expression in the body. Exosomes have recently emerged as a promising drug delivery vehicle due to their low immunogenicity, nanoscale size (30-150nm), high biocompatibility, and stability in the targeted area. Exosomes, which are genetically produced by different types of cells such as dendritic cells, neurons, T and B cells, epithelial cells, tumor cells, and mast cells, are designed for efficient delivery to targeted cells. In this article, we review and highlight recent developments in the strategy and application of exosome-based HIV-1 vaccines. We also discuss the use of exosome-based antigen delivery systems in vaccine development. HIV-1 antigen can be loaded into exosomes, and this modified cargo can be delivered to target cells or tissues through different loading approaches. This review also discusses the immunological prospects of exosomes and their role as biomarkers in disease progression. However, there are significant administrative and technological obstacles that need to be overcome to fully harness the potential of exosome drug delivery systems.


Assuntos
Exossomos , HIV-1 , Humanos , Exossomos/metabolismo , Sistemas de Liberação de Medicamentos , Desenvolvimento de Vacinas
11.
Sci Rep ; 13(1): 20065, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973920

RESUMO

The vaginal microenvironment is key in mediating susceptibility to sexually transmitted infections. A polymicrobial environment with reduced Lactobacilllus spp. is characteristic of vaginal dysbiosis, associated with increased production of several short chain fatty acids (SCFAs), vaginal inflammation and an increased risk of HIV-1 acquisition. In contrast, a eubiotic vaginal microbiome (VMB), dominated by Lactobacillus spp. correlates with increased production of lactic acid (LA), an acidic milieu and protection against HIV-1. Vaginal metabolites, specifically LA and SCFAs including butyric, succinic and acetic acids are associated with modulation of HIV-1 risk. We assessed the impact of combined and individual SCFAs and LA on vaginal epithelial cells (VK2) grown in air-liquid interface cultures. Treatment of VK2 cells with eubiotic SCFA + LA mixture showed increased epithelial barrier integrity, reduced FITC dextran leakage and enhanced expression of cell-cell adhesion proteins. Treatment with dysbiotic SCFA + LA mixture diminished epithelial barrier integrity, increased NFκB activation and inflammatory mediators: TNF-α, IL-6, IL-8 and RANTES. LA was found to be the primary contributor of the beneficial effects. Eubiotic SCFA + LA mixture ameliorated HIV-1 mediated barrier disruption and HIV-1 leakage, whereas dysbiotic SCFA + LA treatment exacerbated HIV-1 effects. These findings indicate a key role for LA in future prophylactic strategies.


Assuntos
Soropositividade para HIV , HIV-1 , Feminino , Humanos , HIV-1/fisiologia , Ácido Láctico/farmacologia , Ácido Láctico/metabolismo , Disbiose , Vagina/metabolismo , Ácidos Graxos Voláteis/farmacologia , Ácidos Graxos Voláteis/metabolismo
12.
Nat Commun ; 14(1): 7353, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990014

RESUMO

Although the human immunodeficiency virus type 1 lipid envelope has been reported to be enriched with host cell sphingomyelin and cholesterol, the molecular mechanism of the enrichment is not well understood. Viral Gag protein plays a central role in virus budding. Here, we report the interaction between Gag and host cell lipids using different quantitative and super-resolution microscopy techniques in combination with specific probes that bind endogenous sphingomyelin and cholesterol. Our results indicate that Gag in the inner leaflet of the plasma membrane colocalizes with the outer leaflet sphingomyelin-rich domains and cholesterol-rich domains, enlarges sphingomyelin-rich domains, and strongly restricts the mobility of sphingomyelin-rich domains. Moreover, Gag multimerization induces sphingomyelin-rich and cholesterol-rich lipid domains to be in close proximity in a curvature-dependent manner. Our study suggests that Gag binds, coalesces, and reorganizes pre-existing lipid domains during assembly.


Assuntos
HIV-1 , Humanos , HIV-1/metabolismo , Esfingomielinas/metabolismo , Membrana Celular/metabolismo , Produtos do Gene gag/metabolismo , Colesterol/metabolismo , Microdomínios da Membrana/metabolismo
13.
Pharmacol Res Perspect ; 11(6): e01151, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37961928

RESUMO

GSK3640254 (GSK'254) is a novel HIV-1 maturation inhibitor with pharmacokinetics supporting once-daily (QD) therapy for HIV-1 treatment. This thorough QT/corrected QT (QTc) study evaluated the effect of GSK'254 on cardiac repolarization. In this two-part, randomized study, healthy participants received GSK'254 or placebo QD for 7 days (part 1) to determine safety and pharmacokinetics of a 500-mg supratherapeutic dose. Four sequential treatment periods composed the main QTc study (part 2): GSK'254 100 mg, GSK'254 500 mg, placebo QD for 7 days, or placebo QD for 6 days with a 400-mg moxifloxacin dose on Day 7 (all with a moderate-fat meal). Concentration-QTc analyses modeled the relationship between GSK'254 plasma concentrations and placebo-adjusted change from baseline in QT interval corrected with Fridericia's formula (ΔΔQTcF). Of 50 participants enrolled, 48 completed the study (part 1, 8/8; part 2, 40/42). Least-squares (LS) mean change from baseline in QTcF for GSK'254 100 mg followed the placebo pattern across time points (maximum LS mean ΔΔQTcF, 1.7 ms); the upper bound of the 90% CI remained <10 ms. Maximum LS mean ΔΔQTcF for GSK'254 500 mg exceeded the 10-ms threshold: 10.6 ms (90% CI 7.75-13.38). Neither GSK'254 dose had clinically relevant effects on heart rate or cardiac conduction. By concentration-QTc analysis, no effect on ΔΔQTcF >10 ms is expected up to GSK'254 concentrations of ~3070 ng mL-1 . No clinically relevant effects on cardiac parameters were seen in healthy participants with GSK'254 at the 100-mg dose.


Assuntos
HIV-1 , Humanos , Eletrocardiografia , Fluoroquinolonas , Voluntários Saudáveis , Método Duplo-Cego
14.
Sci Adv ; 9(44): eadh3642, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37922361

RESUMO

Unintegrated retroviral DNA is transcriptionally silenced by host chromatin silencing factors. Here, we used the proteomics of isolated chromatin segments method to reveal viral and host factors associated with unintegrated HIV-1DNA involved in its silencing. By gene silencing using siRNAs, 46 factors were identified as potential repressors of unintegrated HIV-1DNA. Knockdown and knockout experiments revealed POLE3 as a transcriptional repressor of unintegrated HIV-1DNA. POLE3 maintains unintegrated HIV-1DNA in a repressive chromatin state, preventing RNAPII recruitment to the viral promoter. POLE3 and the recently identified host factors mediating unintegrated HIV-1 DNA silencing, CAF1 and SMC5/SMC6/SLF2, show specificity toward different forms of unintegrated HIV-1DNA. Loss of POLE3 impaired HIV-1 replication, suggesting that repression of unintegrated HIV-1DNA is important for optimal viral replication. POLE3 depletion reduces the integration efficiency of HIV-1. POLE3, by maintaining a repressive chromatin structure of unintegrated HIV-1DNA, ensures HIV-1 escape from innate immune sensing in primary CD4+ T cells.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , DNA Viral/genética , Cromatina/genética , Integração Viral , Infecções por HIV/genética , Imunidade Inata
15.
Virulence ; 14(1): 2278254, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37941373

RESUMO

In this study, we examined the occurrence of acquired and transmitted drug resistance to integrase strand transfer inhibitor (INSTI) in HIV-1 strains in Chongqing (China) for guiding for the routine testing of INSTI-associated HIV-1 genotype resistance. Plasma samples were obtained from HIV-1 patients at Chongqing Public Health Medical Center from July 2019 to August 2022. Besides, amplification, sequence, and analysis of the portion of the HIV-1 pol gene that encodes the integrase protein were implemented to identify INSTI resistance. Integrase sequence data was harvested for a comprehensive cohort of 1032 patients infected with HIV-1. This cohort consisted of 564 ART-naive patients, 465 ART-treated patients, and 3 patients with an unknown treatment history. Within the study group, we identified INSTI resistance in 21 patients (2.03%, 21/1032), including 17 ART-treated patients (3.66%, 17/465). Among the ART-treated patients, 12 were INSTI-treated (11.76%, 12/102), 5 were INSTI-naive (1.38%, 5/363), and 4 were ART-ineffective patients (0.71%, 4/564). The prevalent major resistance mutation was Q148R (0.48%, 5/1032), while the most prevalent accessory resistance mutation was E157Q (1.65%, 17/1032). In light of the above, it is recommended that the incidence of accessory genotype analysis should be considered before starting any future INSTI-based therapy, especially in patients with drug resistance to NRTIs and NNRTIs and the reduction of INSTI sensitivity should be carefully monitored and investigated. Regular monitoring for resistance should be implemented after the use of INSTIs, and, importantly, ongoing monitoring of the decreasing susceptibility to INSTIs is crucial following the initiation of treatment with INSTIs.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Humanos , HIV-1/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Prevalência , Integrase de HIV/genética , Integrase de HIV/farmacologia , Farmacorresistência Viral/genética , Mutação , Genótipo , China/epidemiologia
16.
Nat Commun ; 14(1): 7274, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37949879

RESUMO

The HIV-1 Tat protein hijacks the Super Elongation Complex (SEC) to stimulate viral transcription and replication. However, the mechanisms underlying Tat activation and inactivation, which mediate HIV-1 productive and latent infection, respectively, remain incompletely understood. Here, through a targeted complementary DNA (cDNA) expression screening, we identify PRMT2 as a key suppressor of Tat activation, thus contributing to proviral latency in multiple cell line latency models and in HIV-1-infected patient CD4+ T cells. Our data reveal that the transcriptional activity of Tat is oppositely regulated by NPM1-mediated nucleolar retention and AFF4-induced phase separation in the nucleoplasm. PRMT2 preferentially methylates Tat arginine 52 (R52) to reinforce its nucleolar sequestration while simultaneously counteracting its incorporation into the SEC droplets, thereby leading to its functional inactivation to promote proviral latency. Thus, our studies unveil a central and unappreciated role for Tat methylation by PRMT2 in connecting its subnuclear distribution, liquid droplet formation, and transactivating function, which could be therapeutically targeted to eradicate latent viral reservoirs.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/fisiologia , Fatores de Elongação da Transcrição/metabolismo , Linhagem Celular , Provírus/genética , Linfócitos T/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Latência Viral/genética , Infecções por HIV/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
17.
Nat Commun ; 14(1): 7218, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940661

RESUMO

Broadly neutralizing antibodies (bnAbs) against HIV-1 target conserved envelope (Env) epitopes to block viral replication. Here, using structural analyses, we provide evidence to explain why a vaccine targeting the membrane-proximal external region (MPER) of HIV-1 elicits antibodies with human bnAb-like paratopes paradoxically unable to bind HIV-1. Unlike in natural infection, vaccination with MPER/liposomes lacks a necessary structure-based constraint to select for antibodies with an adequate approach angle. Consequently, the resulting Abs cannot physically access the MPER crawlspace on the virion surface. By studying naturally arising Abs, we further reveal that flexibility of the human IgG3 hinge mitigates the epitope inaccessibility and additionally facilitates Env spike protein crosslinking. Our results suggest that generation of IgG3 subtype class-switched B cells is a strategy for anti-MPER bnAb induction. Moreover, the findings illustrate the need to incorporate topological features of the target epitope in immunogen design.


Assuntos
Infecções por HIV , HIV-1 , Vacinas , Humanos , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Sítios de Ligação de Anticorpos , Epitopos , Imunoglobulina G , Proteína gp41 do Envelope de HIV/química
18.
Lancet Glob Health ; 11(12): e1885-e1898, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973339

RESUMO

BACKGROUND: People who inject drugs are disproportionately affected by HIV and hepatitis C virus (HCV) infections, while there is little global data on HIV and HCV testing and treatment coverage of this population. We conducted a systematic review to evaluate country-level, regional, and global coverage of HIV and HCV testing and treatment among people who inject drugs. METHODS: We did a systematic review, and searched bibliographic databases (MEDLINE, Embase, and PsycINFO) and grey literature for studies published between Jan 1, 2017, and April 30, 2022, that evaluated the proportion of people who inject drugs who received testing or treatment for HIV or HCV. For each country, we estimated the proportion of people who inject drugs tested for HIV antibodies in the past 12 months (recent), people who inject drugs ever tested for HCV antibodies and HCV RNA, people who inject drugs with HIV currently receiving antiretroviral therapy, and people who inject drugs with HCV ever receiving HCV antiviral treatment. Regional and global estimates, weighted by the population size of people who inject drugs, were generated where sufficient data were available. This study is registered with PROSPERO (CRD42020173974). FINDINGS: 512 documents reported data eligible for analyses, including 337 peer-reviewed articles, 27 conference abstracts or presentations, and 148 documents from grey literature or supplementary searches. Data of recent HIV antibody testing were available for 67 countries and ever having had HCV antibody testing were available for 49 countries. Globally, an estimated 48·8% of people who inject drugs were recently tested for HIV antibodies (95% uncertainty interval [UI] 43·3-54·2%; range 0·9-86·0%), and 47·1% had ever been tested for HCV antibodies (95% UI 43·4-51·0%; range 0·0-93·3%). HCV RNA testing data were available from three countries. Coverage of HIV antibody testing was high (>75%) in four countries and for HCV antibody testing in 15 countries. The estimated uptake of current HIV treatment (18 countries) ranged from 2·6% to 81·9%, and the estimated uptake of ever having HCV treatment (23 countries) ranged from 1·8% to 88·6% across countries. Uptake of HIV treatment was high in two countries, and of HCV treatment in one country. INTERPRETATION: HIV and HCV testing and treatment uptake among people who inject drugs was highly variable, and suboptimal in most countries. Strategies to improve access to HIV and HCV care among people who inject drugs and the availability of public health surveillance are urgently required. FUNDING: Australian National Health and Medical Research Council and UK National Institute for Health and Care Research Health Protection Research Unit in Behavioural Science and Evaluation.


Assuntos
Usuários de Drogas , Infecções por HIV , HIV-1 , Hepatite C , Abuso de Substâncias por Via Intravenosa , Humanos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Anticorpos Anti-HIV/uso terapêutico , Anticorpos Anti-Hepatite C/uso terapêutico , Austrália , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Hepacivirus , RNA/uso terapêutico
19.
PLoS One ; 18(11): e0287829, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37910521

RESUMO

Interleukin (IL)-27, a member of the IL-12 family of cytokines, induces human immunodeficiency virus (HIV)-resistant monocyte-derived macrophages and T cells. This resistance is mediated via the downregulation of spectrin beta, non-erythrocytic 1 (SPTBN1), induction of autophagy, or suppression of the acetylation of Y-box binding protein-1 (YB-1); however, the role of IL-27 administration during the induction of immature monocyte-derived dendritic cells (iDC) is poorly investigated. In the current study, we investigated the function of IL-27-induced iDC (27DC) on HIV infection. 27DC inhibited HIV infection by 95 ± 3% without significant changes in the expression of CD4, CCR5, and SPTBN1 expression, autophagy induction and acetylation of YB-1 compared to iDC. An HIV proviral DNA copy number assay displayed that 27DC suppressed reverse transcriptase (RT) reaction without influencing the virus entry. A DNA microarray analysis was performed to identify the differentially expressed genes between 27DC and iDC. Compared to iDC, 51 genes were differentially expressed in 27DC, with more than 3-fold changes in four independent donors. Cross-reference analysis with the reported 2,214 HIV regulatory host genes identified nine genes as potential interests: Ankyrin repeat domain 22, Guanylate binding protein (GBP)-1, -2, -4, -5, Stabilin 1, Serpin family G member 1 (SERPING1), Interferon alpha inducible protein 6, and Interferon-induced protein with tetratricopeptide repeats 3. A knock-down study using si-RNA failed to determine a key factor associated with the anti-HIV activity due to the induction of robust amounts of off-target effects. Overexpression of each protein in cells had no impact on HIV infection. Thus, we could not define the mechanism of the anti-HIV effect in 27DC. However, our findings indicated that IL-27 differentiates monocytes into HIV-resistant DC, and the inhibitory mechanism differs from IL-27-induced HIV-resistant macrophages and T cells.


Assuntos
Infecções por HIV , HIV-1 , Interleucina-27 , Humanos , Internalização do Vírus , Interleucinas/metabolismo , Monócitos , Autofagia/genética , DNA/metabolismo , Células Dendríticas/metabolismo , Replicação Viral , Espectrina/metabolismo
20.
Front Public Health ; 11: 1225883, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37942240

RESUMO

Objective: HIV/AIDS remains a global public health problem, and understanding the structure of social networks of people living with HIV/AIDS is of great importance to unravel HIV transmission, propose precision control and reduce new infections. This study aimed to investigate the epidemiological characteristics of HIV transmission in Fujian province, southeastern China from 2015 to 2020 based on HIV molecular network. Methods: Newly diagnosed, treatment-naive HIV/AIDS patients were randomly sampled from Fujian province in 2015 and 2020. Plasma was sampled for in-house genotyping resistance test, and HIV molecular network was created using the HIV-TRACE tool. Factors affecting the inclusion of variables in the HIV molecular network were identified using univariate and multivariate logistic regression analyses. Results: A total of 1,714 eligible cases were finally recruited, including 806 cases in 2015 and 908 cases in 2020. The dominant HIV subtypes were CRF01_AE (41.7%) and CRF07_BC (38.3%) in 2015 and CRF07_BC (53. 3%) and CRF01_AE (29.1%) in 2020, and the prevalence of HIV drug resistance was 4.2% in 2015 and 5.3% in 2020. Sequences of CRF07_BC formed the largest HIV-1 transmission cluster at a genetic distance threshold of both 1.5 and 0.5%. Univariate and multivariate logistic regression analyses showed that ages of under 20 years and over 60 years, CRF07_BC subtype, Han ethnicity, sampling in 2015, absence of HIV drug resistance, married with spouse, sampling from three cities of Jinjiang, Nanping and Quanzhou resulted in higher proportions of sequences included in the HIV transmission molecular network at a genetic distance threshold of 1.5% (p < 0.05). Conclusion: Our findings unravel the HIV molecular transmission network of newly diagnosed HIV/AIDS patients in Fujian province, southeastern China, which facilitates the understanding of HIV transmission patterns in the province.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , HIV-1 , Humanos , Síndrome de Imunodeficiência Adquirida/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/diagnóstico , HIV-1/genética , Epidemiologia Molecular , China/epidemiologia
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