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BACKGROUND: There are gaps in uptake of, adherence to, and persistence in the use of preexposure prophylaxis for human immunodeficiency virus (HIV) prevention among cisgender women. METHODS: We conducted a phase 3, double-blind, randomized, controlled trial involving adolescent girls and young women in South Africa and Uganda. Participants were assigned in a 2:2:1 ratio to receive subcutaneous lenacapavir every 26 weeks, daily oral emtricitabine-tenofovir alafenamide (F/TAF), or daily oral emtricitabine-tenofovir disoproxil fumarate (F/TDF; active control); all participants also received the alternate subcutaneous or oral placebo. We assessed the efficacy of lenacapavir and F/TAF by comparing the incidence of HIV infection with the estimated background incidence in the screened population and evaluated relative efficacy as compared with F/TDF. RESULTS: Among 5338 participants who were initially HIV-negative, 55 incident HIV infections were observed: 0 infections among 2134 participants in the lenacapavir group (0 per 100 person-years; 95% confidence interval [CI], 0.00 to 0.19), 39 infections among 2136 participants in the F/TAF group (2.02 per 100 person-years; 95% CI, 1.44 to 2.76), and 16 infections among 1068 participants in the F/TDF group (1.69 per 100 person-years; 95% CI, 0.96 to 2.74). Background HIV incidence in the screened population (8094 participants) was 2.41 per 100 person-years (95% CI, 1.82 to 3.19). HIV incidence with lenacapavir was significantly lower than background HIV incidence (incidence rate ratio, 0.00; 95% CI, 0.00 to 0.04; P<0.001) and than HIV incidence with F/TDF (incidence rate ratio, 0.00; 95% CI, 0.00 to 0.10; P<0.001). HIV incidence with F/TAF did not differ significantly from background HIV incidence (incidence rate ratio, 0.84; 95% CI, 0.55 to 1.28; P = 0.21), and no evidence of a meaningful difference in HIV incidence was observed between F/TAF and F/TDF (incidence rate ratio, 1.20; 95% CI, 0.67 to 2.14). Adherence to F/TAF and F/TDF was low. No safety concerns were found. Injection-site reactions were more common in the lenacapavir group (68.8%) than in the placebo injection group (F/TAF and F/TDF combined) (34.9%); 4 participants in the lenacapavir group (0.2%) discontinued the trial regimen owing to injection-site reactions. CONCLUSIONS: No participants receiving twice-yearly lenacapavir acquired HIV infection. HIV incidence with lenacapavir was significantly lower than background HIV incidence and HIV incidence with F/TDF. (Funded by Gilead Sciences; PURPOSE 1 ClinicalTrials.gov number, NCT04994509.).
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BACKGROUND: We sought to identify factors associated with weight gain in randomized clinical trials of antiretroviral therapy (ART) switch. METHODS: We explored the effects of demographic factors, clinical characteristics, and ART on weight gain in a pooled analysis of 12 prospective clinical trials, wherein virologically suppressed people living with human immunodeficiency virus (PWH) were randomized to switch or remain on a stable baseline regimen (SBR). RESULTS: Both PWH randomized to switch ART (nâ =â 4166) and those remaining on SBR (nâ =â 3150) gained weight. Median weight gain was greater in those who switched (1.6 kg, interquartile range [IQR], -.05 to 4.0 vs 0.4 kg, [IQR], -1.8 to 2.4 at 48 weeks, Pâ <â .0001), with most weight gain occurring in the first 24 weeks after switch. Among baseline demographic and clinical characteristics, only younger age and lower baseline body mass index were associated with any or ≥10% weight gain. By week 48, 4.6% gained ≥10% weight (6.4% of switch and 2.2% of SBR), the greatest risk was with switch from efavirenz (EFV) to rilpivirine (RPV) or elvitegravir/cobicistat and switch from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF). Switch from abacavir to TAF was associated with less weight gain than switch from TDF to TAF and was not associated with increased risk for ≥10% weight gain. CONCLUSIONS: Moderate weight gain after ART switch was common and usually plateaued by 48 weeks. Baseline ART was a predictor of post-switch weight gain; participants who switched off of EFV and TDF had the greatest weight gain. The biological mechanisms that underlie the differential effects of switching ART agents on weight and associated clinical implications require further study.
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Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tenofovir/uso terapêuticoRESUMO
BACKGROUND: Initiation of antiretroviral therapy (ART) often leads to weight gain. While some of this weight gain may be an appropriate return-to-health effect, excessive increases in weight may lead to obesity. We sought to explore factors associated with weight gain in several randomized comparative clinical trials of ART initiation. METHODS: We performed a pooled analysis of weight gain in 8 randomized controlled clinical trials of treatment-naive people living with human immunodeficiency virus (HIV) initiating ART between 2003 and 2015, comprising >5000 participants and 10 000 person-years of follow-up. We used multivariate modeling to explore relationships between demographic factors, HIV disease characteristics, and ART components and weight change following ART initiation. RESULTS: Weight gain was greater in more recent trials and with the use of newer ART regimens. Pooled analysis revealed baseline demographic factors associated with weight gain including lower CD4 cell count, higher HIV type 1 RNA, no injection drug use, female sex, and black race. Integrase strand transfer inhibitor use was associated with more weight gain than were protease inhibitors or nonnucleoside reverse transcriptase inhibitors (NNRTIs), with dolutegravir and bictegravir associated with more weight gain than elvitegravir/cobicistat. Among the NNRTIs, rilpivirine was associated with more weight gain than efavirenz. Among nucleoside/nucleotide reverse transcriptase inhibitors, tenofovir alafenamide was associated with more weight gain than tenofovir disoproxil fumarate, abacavir, or zidovudine. CONCLUSIONS: Weight gain is ubiquitous in clinical trials of ART initiation and is multifactorial in nature, with demographic factors, HIV-related factors, and the composition of ART regimens as contributors. The mechanisms by which certain ART agents differentially contribute to weight gain are unknown.
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Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/efeitos adversos , Antirretrovirais/efeitos adversos , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Fatores de Risco , Tenofovir/uso terapêutico , Aumento de PesoRESUMO
Long interspersed element-1 (LINE-1 or L1) retrotransposition continues to affect human genome evolution. L1s can retrotranspose in the germline, during early development and in select somatic cells; however, the host response to L1 retrotransposition remains largely unexplored. Here we show that reporter genes introduced into the genome of various human embryonic carcinoma-derived cell lines (ECs) by L1 retrotransposition are rapidly and efficiently silenced either during or immediately after their integration. Treating ECs with histone deacetylase inhibitors rapidly reverses this silencing, and chromatin immunoprecipitation experiments revealed that reactivation of the reporter gene was correlated with changes in chromatin status at the L1 integration site. Under our assay conditions, rapid silencing was also observed when reporter genes were delivered into ECs by mouse L1s and a zebrafish LINE-2 element, but not when similar reporter genes were delivered into ECs by Moloney murine leukaemia virus or human immunodeficiency virus, suggesting that these integration events are silenced by distinct mechanisms. Finally, we demonstrate that subjecting ECs to culture conditions that promote differentiation attenuates the silencing of reporter genes delivered by L1 retrotransposition, but that differentiation, in itself, is not sufficient to reactivate previously silenced reporter genes. Thus, our data indicate that ECs differ from many differentiated cells in their ability to silence reporter genes delivered by L1 retrotransposition.
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Células-Tronco de Carcinoma Embrionário/metabolismo , Epigênese Genética/genética , Inativação Gênica , Retroelementos/genética , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Células-Tronco de Carcinoma Embrionário/patologia , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Genes Reporter/genética , Engenharia Genética , Vetores Genéticos/genética , Genoma Humano/genética , HIV/genética , Inibidores de Histona Desacetilases/farmacologia , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Masculino , Camundongos , Modelos Genéticos , Vírus da Leucemia Murina de Moloney/genética , Peixe-Zebra/genéticaRESUMO
The Nef protein is an important HIV virulence factor that promotes the degradation of host proteins to augment virus production and facilitate immune evasion. The best-characterized targets of Nef are major histocompatibility complex class I (MHC-I) and CD4, but Nef also has been reported to target several other proteins, including CD8ß, CD28, CD80, CD86, and CD1d. To compare and contrast the effects of Nef on each protein, we constructed a panel of chimeric proteins in which the extracellular and transmembrane regions of the MHC-I allele HLA-A2 were fused to the cytoplasmic tails of CD4, CD28, CD8ß, CD80, CD86, and CD1d. We found that Nef coprecipitated with and disrupted the expression of molecules with cytoplasmic tails from MHC-I HLA-A2, CD4, CD8ß, and CD28, but Nef did not bind to or alter the expression of molecules with cytoplasmic tails from CD80, CD86, and CD1d. In addition, we used short interfering RNA (siRNA) knockdown and coprecipitation experiments to implicate AP-1 as a cellular cofactor for Nef in the downmodulation of both CD28 and CD8ß. The interaction with AP-1 required for CD28 and CD8ß differed from the AP-1 interaction required for MHC-I downmodulation in that it was mediated through the dileucine motif within Nef (LL(164,165)AA) and did not require the tyrosine binding pocket of the AP-1 µ subunit. In addition, we demonstrate a requirement for ß-COP as a cellular cofactor for Nef that was necessary for the degradation of targeted molecules HLA-A2, CD4, and CD8. These studies provide important new information on the similarities and differences with which Nef affects intracellular trafficking and help focus future research on the best potential pharmaceutical targets.
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Antígenos CD28/imunologia , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Alelos , Sequência de Bases , Western Blotting , Linhagem Celular , Clonagem Molecular , Primers do DNA , Citometria de Fluxo , Reação em Cadeia da Polimerase , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana/fisiologiaRESUMO
The mechanistic target of rapamycin (mTOR) functions in two distinct complexes: mTORC1, and mTORC2. mTORC1 has been implicated in the pathogenesis of flaviviruses including dengue, where it contributes to the establishment of a pro-viral autophagic state. Activation of mTORC2 occurs upon infection with some viruses, but its functional role in viral pathogenesis remains poorly understood. In this study, we explore the consequences of a physical protein-protein interaction between dengue non-structural protein 5 (NS5) and host cell mTOR proteins during infection. Using shRNA to differentially target mTORC1 and mTORC2 complexes, we show that mTORC2 is required for optimal dengue replication. Furthermore, we show that mTORC2 is activated during viral replication, and that mTORC2 counteracts virus-induced apoptosis, promoting the survival of infected cells. This work reveals a novel mechanism by which the dengue flavivirus can promote cell survival to maximize viral replication.
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Dengue , Complexos Multiproteicos , Apoptose , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , RNA Interferente Pequeno , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Replicação ViralRESUMO
OBJECTIVES: Remdesivir shortens time to recovery in adults with severe coronavirus disease 2019 (COVID-19), but its efficacy and safety in children are unknown. We describe outcomes in children with severe COVID-19 treated with remdesivir. METHODS: Seventy-seven hospitalized patients <18 years old with confirmed severe acute respiratory syndrome coronavirus 2 infection received remdesivir through a compassionate-use program between March 21 and April 22, 2020. The intended remdesivir treatment course was 10 days (200 mg on day 1 and 100 mg daily subsequently for children ≥40 kg and 5 mg/kg on day 1 and 2.5 mg/kg daily subsequently for children <40 kg, given intravenously). Clinical data through 28 days of follow-up were collected. RESULTS: Median age was 14 years (interquartile range 7-16, range <2 months to 17 years). Seventy-nine percent of patients had ≥1 comorbid condition. At baseline, 90% of children required supplemental oxygen and 51% required invasive ventilation. By day 28 of follow-up, 88% of patients had a decreased oxygen-support requirement, 83% recovered, and 73% were discharged. Among children requiring invasive ventilation at baseline, 90% were extubated, 80% recovered, and 67% were discharged. There were 4 deaths, of which 3 were attributed to COVID-19. Remdesivir was well tolerated, with a low incidence of serious adverse events (16%). Most adverse events were related to COVID-19 or comorbid conditions. Laboratory abnormalities, including elevations in transaminase levels, were common; 61% were grades 1 or 2. CONCLUSIONS: Among 77 children treated with remdesivir for severe COVID-19, most recovered and the rate of serious adverse events was low.
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Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/uso terapêutico , Adolescente , Alanina/efeitos adversos , Alanina/uso terapêutico , Antivirais/efeitos adversos , COVID-19/diagnóstico , Criança , Pré-Escolar , Ensaios de Uso Compassivo , Quimioterapia Combinada , Feminino , Hospitalização , Humanos , Lactente , Masculino , Oxigenoterapia , Respiração Artificial , SARS-CoV-2 , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
Cellular decisions in human development, homeostasis, regeneration, and disease are coordinated in large part by signals that are spatially localized in tissues. These signals are often soluble, such that biomolecules produced by one cell diffuse to receiving cells. To recapitulate soluble factor patterning in vitro, several microscale strategies have been developed. However, these techniques often introduce new variables into cell culture experiments (e.g., fluid flow) or are limited in their ability to pattern diverse solutes in a user-defined manner. To address these challenges, we developed an adaptable method that facilitates spatial presentation of biomolecules across cells in traditional open cultures in vitro. This technique employs device inserts that are placed in standard culture wells, which support localized diffusive pattern transmission through microscale spaces between device features and adherent cells. Devices can be removed and cultures can be returned to standard media following patterning. We use this method to spatially control cell labeling with pattern features ranging in scale from several hundred microns to millimeters and with sequential application of multiple patterns. To better understand the method we investigate relationships between pattern fidelity, device geometry, and consumption and diffusion kinetics using finite element modeling. We then apply the method to spatially defining reporter cell heterogeneity by patterning a small molecule modulator of genetic recombination with the requisite sustained exposure. Finally, we demonstrate use of this method for patterning larger and more slowly diffusing particles by creating focal sites of gene delivery and infection with adenoviral, lentiviral, and Zika virus particles. Thus, our method leverages devices that interface with standard culture vessels to pattern diverse diffusible factors, geometries, exposure dynamics, and recipient cell types, making it well poised for adoption by researchers across various fields of biological research.
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Células Endoteliais da Veia Umbilical Humana/citologia , Hidrogéis/química , Técnicas Analíticas Microfluídicas , Adenoviridae/isolamento & purificação , Adesão Celular , Células Cultivadas , Difusão , Células HEK293 , Humanos , Imuno-Histoquímica , Técnicas Analíticas Microfluídicas/instrumentação , Poliestirenos/químicaRESUMO
In recent studies, strains of non-dysenteriae 1 Shigella (NDS) expressing Shiga toxin have been reported. In this study, we report a novel stx1a-converting bacteriophage of Shigella sonnei associated with travel to Mexico. Phylogenetic comparison between this and other stx-converting phages suggests that toxigenic NDS strains have arisen through separate horizontal transfer events from toxigenic Escherichia coli.
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To better understand the dynamics of HIV-specific neutralizing antibody (NAb), we examined associations between viral genetic diversity and the NAb response against a multi-subtype panel of heterologous viruses in a well-characterized, therapy-naïve primary infection cohort. Using next generation sequencing (NGS), we computed sequence-based measures of diversity within HIV-1 env, gag and pol, and compared them to NAb breadth and potency as calculated by a neutralization score. Contemporaneous env diversity and the neutralization score were positively correlated (p=0.0033), as were the neutralization score and estimated duration of infection (EDI) (p=0.0038), and env diversity and EDI (p=0.0005). Neither early env diversity nor baseline viral load correlated with future NAb breadth and potency (p>0.05). Taken together, it is unlikely that neutralizing capability in our cohort was conditioned on viral diversity, but rather that env evolution was driven by the level of NAb selective pressure.
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Anticorpos Neutralizantes/biossíntese , Variação Genética , Anticorpos Anti-HIV/biossíntese , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Estudos de Coortes , Genes env , Genes gag , Genes pol , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/imunologia , Humanos , Estudos Longitudinais , Fatores de TempoRESUMO
HIV infection is characterized by gradual immune system collapse and hematopoietic dysfunction. We recently showed that HIV enters multipotent hematopoietic progenitor cells and establishes both active cytotoxic and latent infections that can be reactivated by myeloid differentiation. However, whether these multipotent progenitors include long-lived hematopoietic stem cells (HSCs) that could establish viral reservoirs for the life of the infected person remains unknown. Here we provide direct evidence that HIV targets long-lived HSCs and show that infected HSCs yield stable, multilineage engraftment in a xenograft model. Furthermore, we establish that the capacity to use the chemokine receptor CXCR4 for entry determines whether a virus will enter multipotent versus differentiated progenitor cells. Because HSCs live for the life span of the infected person and are crucial for hematopoietic health, these data may explain the poor prognosis associated with CXCR4-tropic HIV infection and suggest HSCs as long-lived cellular reservoirs of latent HIV.
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Infecções por HIV/patologia , HIV-1/fisiologia , Células-Tronco Hematopoéticas/virologia , Receptores CXCR4/metabolismo , Antígeno AC133 , Animais , Antígenos CD/metabolismo , Antígenos CD4/metabolismo , Contagem de Células , Células Cultivadas , Clonagem Molecular , Glicoproteínas/metabolismo , Proteínas de Fluorescência Verde/biossíntese , HIV-1/genética , HIV-1/patogenicidade , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Peptídeos/metabolismo , Proteínas Recombinantes/biossíntese , Transplante Heterólogo , Carga Viral , Ensaio de Placa Viral , Tropismo Viral , Latência ViralRESUMO
HIV causes a chronic infection characterized by depletion of CD4(+) T lymphocytes and the development of opportunistic infections. Despite drugs that inhibit viral spread, HIV infection has been difficult to cure because of uncharacterized reservoirs of infected cells that are resistant to highly active antiretroviral therapy (HAART) and the immune response. Here we used CD34(+) cells from infected people as well as in vitro studies of wild-type HIV to show infection and killing of CD34(+) multipotent hematopoietic progenitor cells (HPCs). In some HPCs, we detected latent infection that stably persisted in cell culture until viral gene expression was activated by differentiation factors. A unique reporter HIV that directly detects latently infected cells in vitro confirmed the presence of distinct populations of active and latently infected HPCs. These findings have major implications for understanding HIV bone marrow pathology and the mechanisms by which HIV causes persistent infection.
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Morte Celular , Infecções por HIV/virologia , HIV-1/fisiologia , Células-Tronco Multipotentes/virologia , Latência Viral/fisiologia , Antígeno AC133 , Antígenos CD/imunologia , Antígenos CD34/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , Glicoproteínas/imunologia , Infecções por HIV/imunologia , HIV-1/genética , Células-Tronco Hematopoéticas/virologia , Humanos , Peptídeos/imunologia , Reação em Cadeia da Polimerase , Ativação Viral/fisiologiaRESUMO
A complex of the Adenovirus (Ad) early region 1b 55-kDa (E1b-55kDa) and early region 4 ORF6 34-kDa (E4-34kDa) proteins promotes viral late gene expression. E1b-55kDa and E4-34kDa have leucine-rich nuclear export signals (NESs) similar to that of HIV Rev. It was proposed that E1b-55kDa and/or E4-34kDa might promote the export of Ad late mRNA via their Rev-like NESs, and the transport receptor CRM1. We treated infected cells with the cytotoxin leptomycin B to inhibit CRM1-mediated export; treatment initially delays the onset of late gene expression, but this activity completely recovers as the late phase progresses. We find that the E1b-55kDa NES is not required to promote late gene expression. Previous results showed that E4-34kDa-mediated late gene expression does not require an intact NES (J. Virol. 74 (2000), 6684-6688). Our results indicate that these Ad regulatory proteins promote late gene expression without intact NESs or active CRM1.