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1.
J Virol ; : e0067824, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953380

RESUMO

SARS-CoV-2 variants of concern (VOCs) differentially trigger neutralizing and antibody-dependent cellular cytotoxic (ADCC) antibodies with variable cross-reactivity. Omicron BA.4/5 was approved for inclusion in bivalent vaccination boosters, and therefore the antigenic profile of antibodies elicited by this variant is critical to understand. Here, we investigate the ability of BA.4/5-elicited antibodies following the first documented (primary) infection (n = 13) or breakthrough infection after vaccination (n = 9) to mediate neutralization and FcγRIIIa signaling across multiple SARS-CoV-2 variants including XBB.1.5 and BQ.1. Using a pseudovirus neutralization assay and a FcγRIIIa crosslinking assay to measure ADCC potential, we show that unlike SARS-CoV-2 Omicron BA.1, BA.4/5 infection triggers highly cross-reactive functional antibodies. Cross-reactivity was observed both in the absence of prior vaccination and in breakthrough infections following vaccination. However, BQ.1 and XBB.1.5 neutralization and FcγRIIIa signaling were significantly compromised compared to other VOCs, regardless of prior vaccination status. BA.4/5 triggered FcγRIIIa signaling was significantly more resilient against VOCs (<10-fold decrease in magnitude) compared to neutralization (10- to 100-fold decrease). Overall, this study shows that BA.4/5 triggered antibodies are highly cross-reactive compared to those triggered by other variants. Although this is consistent with enhanced neutralization and FcγRIIIa signaling breadth of BA.4/5 vaccine boosters, the reduced activity against XBB.1.5 supports the need to update vaccines with XBB sublineage immunogens to provide adequate coverage of these highly antibody evasive variants. IMPORTANCE: The continued evolution of SARS-CoV-2 has resulted in a number of variants of concern. Of these, the Omicron sublineage is the most immune evasive. Within Omicron, the BA.4/5 sublineage drove the fifth wave of infection in South Africa prior to becoming the dominant variant globally. As a result this spike sequence was approved as part of a bivalent vaccine booster, and rolled out worldwide. We aimed to understand the cross-reactivity of neutralizing and Fc mediated cytotoxic functions elicited by BA.4/5 infection following infection or breakthrough infection. We find that, in contrast to BA.1 which triggered fairly strain-specific antibodies, BA.4/5 triggered antibodies that are highly cross-reactive for neutralization and antibody-dependent cellular cytotoxicity potential. Despite this cross-reactivity, these antibodies are compromised against highly resistant variants such as XBB.1.5 and BQ.1. This suggests that next-generation vaccines will require XBB sublineage immunogens in order to protect against these evasive variants.

2.
Viruses ; 16(2)2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38400088

RESUMO

HIV-exposed, uninfected (HEU) children present with suboptimal growth and a greater susceptibility to infection in early life when compared to HIV-unexposed, uninfected (HUU) children. The reasons for these findings are poorly understood. We used a metabolomics approach to investigate the metabolic differences between pregnant women living with HIV (PWLWH) and their HEU infants compared to the uninfected and unexposed controls. Untargeted metabolomic profiling was performed using 1H-NMR spectroscopy on maternal plasma at 28 weeks' gestation and infant plasma at birth, 6/10 weeks, and 6 months. PWLWH were older but, apart from a larger 28 week mid-upper-arm circumference, anthropometrically similar to the controls. At all the time points, HEU infants had a significantly reduced growth compared to HUU infants. PWLWH had lower plasma 3-hydroxybutyric acid, acetoacetic acid, and acetic acid levels. In infants at birth, threonine and myo-inositol levels were lower in the HEU group while formic acid levels were higher. At 6/10 weeks, betaine and tyrosine levels were lower in the HEU group. Finally, at six months, 3-hydroxyisobutyric acid levels were lower while glycine levels were higher in the HEU infants. The NMR analysis has provided preliminary information indicating differences between HEU and HUU infants' plasma metabolites involved in energy utilization, growth, and protection from infection.


Assuntos
Infecções por HIV , Lactente , Recém-Nascido , Criança , Humanos , Feminino , Gravidez , Infecções por HIV/prevenção & controle , Mães , Betaína , Metabolômica
3.
AIDS ; 38(6): 791-801, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300257

RESUMO

OBJECTIVE: This study investigated the association of plasma microRNAs before and during antiretroviral therapy (ART) with poor CD4 + T-cell recovery during the first year of ART. DESIGN: MicroRNAs were retrospectively measured in stored plasma samples from people with HIV (PWH) in sub-Saharan Africa who were enrolled in a longitudinal multicountry cohort and who had plasma viral-load less than 50 copies/ml after 12 months of ART. METHODS: First, the levels of 179 microRNAs were screened in a subset of participants from the lowest and highest tertiles of CD4 + T-cell recovery (ΔCD4) ( N  = 12 each). Next, 11 discordant microRNAs, were validated in 113 participants (lowest tertile ΔCD4: n  = 61, highest tertile ΔCD4: n  = 52). For discordant microRNAs in the validation, a pathway analysis was conducted. Lastly, we compared microRNA levels of PWH to HIV-negative controls. RESULTS: Poor CD4 + T-cell recovery was associated with higher levels of hsa-miR-199a-3p and hsa-miR-200c-3p before ART, and of hsa-miR-17-5p and hsa-miR-501-3p during ART. Signaling by VEGF and MET, and RNA polymerase II transcription pathways were identified as possible targets of hsa-miR-199a-3p, hsa-200c-3p, and hsa-miR-17-5p. Compared with HIV-negative controls, we observed lower hsa-miR-326, hsa-miR-497-5p, and hsa-miR-501-3p levels before and during ART in all PWH, and higher hsa-miR-199a-3p and hsa-miR-200c-3p levels before ART in all PWH, and during ART in PWH with poor CD4 + T-cell recovery only. CONCLUSION: These findings add to the understanding of pathways involved in persistent HIV-induced immune dysregulation during suppressive ART.


Assuntos
Infecções por HIV , HIV-1 , MicroRNAs , Humanos , HIV-1/genética , Estudos Retrospectivos , Infecções por HIV/tratamento farmacológico , MicroRNAs/genética , Linfócitos T
4.
Front Immunol ; 14: 1235914, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37646024

RESUMO

Introduction: SARS-CoV-2 elicits a hyper-inflammatory response that contributes to increased morbidity and mortality in patients with COVID-19. In the case of HIV infection, despite effective anti-retroviral therapy, people living with HIV (PLWH) experience chronic systemic immune activation, which renders them particularly vulnerable to the life-threatening pulmonary, cardiovascular and other complications of SARS-CoV-2 co-infection. The focus of the study was a comparison of the concentrations of systemic indicators o\f innate immune dysfunction in SARS-CoV-2-PCR-positive patients (n=174) admitted with COVID-19, 37 of whom were co-infected with HIV. Methods: Participants were recruited from May 2020 to November 2021. Biomarkers included platelet-associated cytokines, chemokines, and growth factors (IL-1ß, IL-6, IL-8, MIP-1α, RANTES, PDGF-BB, TGF-ß1 and TNF-α) and endothelial associated markers (IL-1ß, IL-1Ra, ICAM-1 and VEGF). Results: PLWH were significantly younger (p=0.002) and more likely to be female (p=0.001); median CD4+ T-cell count was 256 (IQR 115 -388) cells/µL and the median HIV viral load (VL) was 20 (IQR 20 -12,980) copies/mL. Fractional inspired oxygen (FiO2) was high in both groups, but higher in patients without HIV infection (p=0.0165), reflecting a greater need for oxygen supplementation. With the exception of PDGF-BB, the levels of all the biomarkers of innate immune activation were increased in SARS-CoV-2/HIV-co-infected and SARS-CoV-2/HIV-uninfected sub-groups relative to those of a control group of healthy participants. The magnitudes of the increases in the levels of these biomarkers were comparable between the SARS-CoV-2 -infected sub-groups, the one exception being RANTES, which was significantly higher in the sub-group without HIV. After adjusting for age, sex, and diabetes in the multivariable model, only the association between HIV status and VEGF was statistically significant (p=0.034). VEGF was significantly higher in PLWH with a CD4+ T-cell count >200 cells/µL (p=0.040) and those with a suppressed VL (p=0.0077). Discussion: These findings suggest that HIV co-infection is not associated with increased intensity of the systemic innate inflammatory response during SARS-CoV-2 co-infection, which may underpin the equivalent durations of hospital stay, outcome and mortality rates in the SARS-CoV-2/HIV-infected and -uninfected sub-groups investigated in the current study. The apparent association of increased levels of plasma VEGF with SARS-CoV-2/HIV co-infection does, however, merit further investigation.


Assuntos
COVID-19 , Coinfecção , Infecções por HIV , Humanos , Feminino , Masculino , SARS-CoV-2 , Quimiocina CCL5 , Becaplermina , Infecções por HIV/complicações , Fator A de Crescimento do Endotélio Vascular , Biomarcadores
5.
Front Immunol ; 14: 1231276, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600825

RESUMO

The kinetics of Fc-mediated functions following SARS-CoV-2 infection or vaccination in people living with HIV (PLWH) are not known. We compared SARS-CoV-2 spike-specific Fc functions, binding, and neutralization in PLWH and people without HIV (PWOH) during acute infection (without prior vaccination) with either the D614G or Beta variants of SARS-CoV-2, or vaccination with ChAdOx1 nCoV-19. Antiretroviral treatment (ART)-naïve PLWH had significantly lower levels of IgG binding, neutralization, and antibody-dependent cellular phagocytosis (ADCP) compared with PLWH on ART. The magnitude of antibody-dependent cellular cytotoxicity (ADCC), complement deposition (ADCD), and cellular trogocytosis (ADCT) was differentially triggered by D614G and Beta. The kinetics of spike IgG-binding antibodies, ADCC, and ADCD were similar, irrespective of the infecting variant between PWOH and PLWH overall. However, compared with PWOH, PLWH infected with D614G had delayed neutralization and ADCP. Furthermore, Beta infection resulted in delayed ADCT, regardless of HIV status. Despite these delays, we observed improved coordination between binding and neutralizing responses and Fc functions in PLWH. In contrast to D614G infection, binding responses in PLWH following ChAdOx-1 nCoV-19 vaccination were delayed, while neutralization and ADCP had similar timing of onset, but lower magnitude, and ADCC was significantly higher than in PWOH. Overall, despite delayed and differential kinetics, PLWH on ART develop comparable responses to PWOH, supporting the prioritization of ART rollout and SARS-CoV-2 vaccination in PLWH.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Citotoxicidade Celular Dependente de Anticorpos , COVID-19 , Infecções por HIV , Fragmentos Fc das Imunoglobulinas , Glicoproteína da Espícula de Coronavírus , Infecções por HIV/sangue , Infecções por HIV/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Fragmentos Fc das Imunoglobulinas/sangue , Fragmentos Fc das Imunoglobulinas/imunologia , ChAdOx1 nCoV-19/imunologia , ChAdOx1 nCoV-19/uso terapêutico , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Vacinação , Glicoproteína da Espícula de Coronavírus/imunologia , Células HEK293 , Humanos , Imunidade Humoral , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
6.
Viruses ; 15(2)2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36851493

RESUMO

With the global rollout of mother-to-child prevention programs for women living with HIV, vertical transmission has been all but eliminated in many countries. However, the number of children who are exposed in utero to HIV and antiretroviral therapy (ART) is ever-increasing. These children who are HIV-exposed-but-uninfected (CHEU) are now well recognized as having persistent health disparities compared to children who are HIV-unexposed-and-uninfected (CHUU). Differences reported between these two groups include immune dysfunction and higher levels of inflammation, cognitive and metabolic abnormalities, as well as increased morbidity and mortality in CHEU. The reasons for these disparities remain largely unknown. The present review focuses on a proposed link between immunometabolic aberrations and clinical pathologies observed in the rapidly expanding CHEU population. By drawing attention, firstly, to the significance of the immune and metabolic alterations observed in these children, and secondly, the impact of their healthcare requirements, particularly in low- and middle-income countries, this review aims to sensitize healthcare workers and policymakers about the long-term risks of in utero exposure to HIV and ART.


Assuntos
Pessoal de Saúde , Transmissão Vertical de Doenças Infecciosas , Gravidez , Humanos , Feminino , Inflamação , Grupo Social
7.
Cell Rep Med ; 4(1): 100910, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36603577

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.4 and BA.5 variants caused major waves of infections. Here, we assess the sensitivity of BA.4 to binding, neutralization, and antibody-dependent cellular cytotoxicity (ADCC) potential, measured by FcγRIIIa signaling, in convalescent donors infected with four previous variants of SARS-CoV-2, as well as in post-vaccination breakthrough infections (BTIs) caused by Delta or BA.1. We confirm that BA.4 shows high-level neutralization resistance regardless of the infecting variant. However, BTIs retain activity against BA.4, albeit at reduced titers. BA.4 sensitivity to ADCC is reduced compared with other variants but with smaller fold losses compared with neutralization and similar patterns of cross-reactivity. Overall, the high neutralization resistance of BA.4, even to antibodies from BA.1 infection, provides an immunological mechanism for the rapid spread of BA.4 immediately after a BA.1-dominated wave. Furthermore, although ADCC potential against BA.4 is reduced, residual activity may contribute to observed protection from severe disease.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Soroterapia para COVID-19 , SARS-CoV-2 , Humanos , Anticorpos , Infecções Irruptivas , COVID-19/imunologia , COVID-19/terapia , SARS-CoV-2/imunologia
8.
Molecules ; 27(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558190

RESUMO

There is increasing awareness of an association between the uptake of the HIV integrase inhibitor, dolutegravir, in first-line antiretroviral regimens with unusual weight gain and development of the metabolic syndrome, particularly in African women. Although seemingly unexplored, the development of systemic inflammation linked to the putative pro-inflammatory activity of dolutegravir represents a plausible pathophysiological mechanism of this unusual weight gain. This possibility was explored in the current study undertaken to investigate the effects of dolutegravir (2.5−20 µg/mL) on several pro-inflammatory activities of neutrophils isolated from the blood of healthy, adult humans. These activities included the generation of reactive oxygen species (ROS), degranulation (elastase release) and alterations in the concentrations of cytosolic Ca2+ using chemiluminescence, spectrophotometric and fluorimetric procedures, respectively. Exposure of neutrophils to dolutegravir alone resulted in the abrupt, dose-related, and significant (p < 0.0039−p < 0.0022) generation of ROS that was attenuated by the inclusion of the Ca2+-chelating agent, EGTA, or inhibitors of NADPH oxidase (diphenyleneiodonium chloride, DPI), phospholipase C (U733122), myeloperoxidase (sodium azide) and phosphoinositol-3-kinase (wortmannin). In addition, exposure to dolutegravir augmented the release of elastase by stimulus-activated neutrophils. These pro-inflammatory effects of dolutegravir on neutrophils were associated with significant, rapid, and sustained increases in the concentrations of cytosolic Ca2+ that appeared to originate from the extracellular compartment, seemingly consistent with an ionophore-like property of dolutegravir. These findings are preliminary and necessitate verification in the clinical setting of HIV infection. Nevertheless, given the complex link between inflammation and obesity, these pro-inflammatory interactions of dolutegravir with neutrophils may contribute to unexplained weight gain, possibly via the development of insulin resistance.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Adulto , Humanos , Feminino , Espécies Reativas de Oxigênio/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Neutrófilos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Compostos Heterocíclicos com 3 Anéis/metabolismo , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , Elastase Pancreática/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo
9.
J Immunotoxicol ; 19(1): 1-8, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36394569

RESUMO

Dolutegravir is a highly potent HIV integrase strand transfer inhibitor that is recommended for first-line anti-retroviral treatment in all major treatment guidelines. A recent study has shown that people taking this class of anti-retroviral treatment have a substantially higher risk of early-onset cardiovascular disease, a condition shown previously to be associated with increased platelet reactivity. To date, few studies have explored the effects of dolutegravir on platelet activation. Accordingly, the current study was undertaken with the primary objective of investigating the effects of dolutegravir on the reactivity of human platelets in vitro. Platelet-rich plasma, isolated platelets, or buffy coat cell suspensions prepared from the blood of healthy adults were treated with dolutegravir (2.5-10 µg/ml), followed by activation with adenosine 5'-diphosphate (ADP), thrombin, or a thromboxane A2 receptor agonist U46619. Expression of platelet CD62P (P-selectin), formation of heterotypic neutrophil:platelet aggregates, and calcium (Ca2+) fluxes were measured using flow cytometry and fluorescence spectrometry, respectively. Dolutegravir caused dose-related potentiation of ADP-, thrombin- and U46619-activated expression of CD62P by platelets, as well as a significant increases in formation of neutrophil:platelet aggregates. These effects were paralleled by a spontaneous, receptor-independent elevation in cytosolic Ca2+ that appears to underpin the mechanism by which the antiretroviral agent augments the responsiveness of these cells to ADP, thrombin and U46619. The most likely mechanism of dolutegravir-mediated increases in platelet cytosolic Ca2+ relates to a combination of lipophilicity and divalent/trivalent metal-binding and/or chelating properties of the anti-retroviral agent. These properties are likely to confer ionophore-type activities on dolutegravir that would promote movement of Ca2+ across the plasma membrane, delivering the cation to the cytosol where it would augment Ca2+-dependent intracellular signaling mechanisms. These effects of dolutegravir may lead to hyper-activation of platelets which, if operative in vivo, may contribute to an increased risk for cardiometabolic co-morbidities.


Assuntos
Cálcio , Infecções por HIV , Adulto , Humanos , Trombina/farmacologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Ativação Plaquetária , Difosfato de Adenosina/farmacologia , Infecções por HIV/tratamento farmacológico , Ionóforos/farmacologia
12.
Cell Rep Med ; 3(3): 100535, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35474744

RESUMO

The Janssen (Johnson & Johnson) Ad26.COV2.S non-replicating viral vector vaccine has been widely deployed for COVID-19 vaccination programs in resource-limited settings. Here we confirm that neutralizing and binding antibody responses to Ad26.COV2.S vaccination are stable for 6 months post-vaccination, when tested against multiple SARS-CoV-2 variants. Secondly, using longitudinal samples from individuals who experienced clinically mild breakthrough infections 4 to 5 months after vaccination, we show dramatically boosted binding antibodies, Fc effector function, and neutralization. These high titer responses are of similar magnitude to humoral immune responses measured in convalescent donors who had been hospitalized with severe illness, and are cross-reactive against diverse SARS-CoV-2 variants, including the neutralization-resistant Omicron (B.1.1.529) variant that currently dominates global infections, as well as SARS-CoV-1. These data have implications for population immunity in areas where the Ad26.COV2.S vaccine has been widely deployed, but where ongoing infections continue to occur at high levels.


Assuntos
COVID-19 , Vacinas Virais , Ad26COVS1 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Humanos , SARS-CoV-2/genética
13.
Cell Host Microbe ; 30(6): 880-886.e4, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35436444

RESUMO

The SARS-CoV-2 Omicron variant escapes neutralizing antibodies elicited by vaccines or infection. However, whether Omicron triggers cross-reactive humoral responses to other variants of concern (VOCs) remains unknown. We used plasma from 20 unvaccinated and 7 vaccinated individuals infected by Omicron BA.1 to test binding, Fc effector function, and neutralization against VOCs. In unvaccinated individuals, Fc effector function and binding antibodies targeted Omicron and other VOCs at comparable levels. However, Omicron BA.1-triggered neutralization was not extensively cross-reactive for VOCs (14- to 31-fold titer reduction), and we observed 4-fold decreased titers against Omicron BA.2. In contrast, vaccination followed by breakthrough Omicron infection associated with improved cross-neutralization of VOCs with titers exceeding 1:2,100. This has important implications for the vulnerability of unvaccinated Omicron-infected individuals to reinfection by circulating and emerging VOCs. Although Omicron-based immunogens might be adequate boosters, they are unlikely to be superior to existing vaccines for priming in SARS-CoV-2-naive individuals.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Humanos , Testes de Neutralização
14.
Cell Rep Med ; 3(2): 100510, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35233544

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants of concern (VOCs) exhibit escape from neutralizing antibodies, causing concern about vaccine effectiveness. However, while non-neutralizing cytotoxic functions of antibodies are associated with improved disease outcome and vaccine protection, Fc effector function escape from VOCs is poorly defined. Furthermore, whether VOCs trigger Fc functions with altered specificity, as has been reported for neutralization, is unknown. Here, we demonstrate that the Beta VOC partially evades Fc effector activity in individuals infected with the original (D614G) variant. However, not all functions are equivalently affected, suggesting differential targeting by antibodies mediating distinct Fc functions. Furthermore, Beta and Delta infection trigger responses with significantly improved Fc cross-reactivity against global VOCs compared with D614G-infected or Ad26.COV2.S-vaccinated individuals. This suggests that, as for neutralization, the infecting spike sequence affects Fc effector function. These data have important implications for vaccine strategies that incorporate VOCs, suggesting these may induce broader Fc effector responses.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , SARS-CoV-2/imunologia , Ad26COVS1/imunologia , Ad26COVS1/uso terapêutico , Adulto , Idoso , COVID-19/sangue , COVID-19/prevenção & controle , COVID-19/virologia , Estudos de Coortes , Reações Cruzadas , Feminino , Células HEK293 , Humanos , Células Jurkat , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/imunologia , Células THP-1 , Resultado do Tratamento , Vacinação/métodos
15.
Front Immunol ; 13: 776861, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185878

RESUMO

Cardiovascular dysfunction and disease are common and frequently fatal complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Indeed, from early on during the SARS-CoV-2 virus pandemic it was recognized that cardiac complications may occur, even in patients with no underlying cardiac disorders, as part of the acute infection, and that these were associated with more severe disease and increased morbidity and mortality. The most common cardiac complication is acute cardiac injury, defined by significant elevation of cardiac troponins. The potential mechanisms of cardiovascular complications include direct viral myocardial injury, systemic inflammation induced by the virus, sepsis, arrhythmia, myocardial oxygen supply-demand mismatch, electrolyte abnormalities, and hypercoagulability. This review is focused on the prevalence, risk factors and clinical course of COVID-19-related myocardial injury, as well as on current data with regard to disease pathogenesis, specifically the interaction of platelets with the vascular endothelium. The latter section includes consideration of the role of SARS-CoV-2 proteins in triggering development of a generalized endotheliitis that, in turn, drives intense activation of platelets. Most prominently, SARS-CoV-2-induced endotheliitis involves interaction of the viral spike protein with endothelial angiotensin-converting enzyme 2 (ACE2) together with alternative mechanisms that involve the nucleocapsid and viroporin. In addition, the mechanisms by which activated platelets intensify endothelial activation and dysfunction, seemingly driven by release of the platelet-derived calcium-binding proteins, SA100A8 and SA100A9, are described. These events create a SARS-CoV-2-driven cycle of intravascular inflammation and coagulation, which contributes significantly to a poor clinical outcome in patients with severe disease.


Assuntos
Plaquetas/metabolismo , COVID-19/patologia , Doenças Cardiovasculares/patologia , Endotélio Vascular/metabolismo , Ativação Plaquetária/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/mortalidade , Doenças Cardiovasculares/virologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Células Endoteliais/metabolismo , Humanos , Miocárdio/patologia , Fosfoproteínas/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
17.
Front Immunol ; 12: 634386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777022

RESUMO

Neutrophils are important components of the innate immune system that mediate pathogen defense by multiple processes including phagocytosis, release of proteolytic enzymes, production of reactive oxygen species, and neutrophil extracellular trap formation. Abnormalities of neutrophil count and function have been described in the setting of HIV infection, with the majority of antiretroviral agents (ARVs), excluding zidovudine, having been reported to correct neutropenia. Questions still remain, however, about their impact on neutrophil function, particularly the possibility of persistent neutrophil activation, which could predispose people living with HIV to chronic inflammatory disorders, even in the presence of virally-suppressive treatment. In this context, the effects of protease inhibitors and integrase strand transfer inhibitors, in particular, on neutrophil function remain poorly understood and deserve further study. Besides mediating hemostatic functions, platelets are increasingly recognized as critical role players in the immune response against infection. In the setting of HIV, these cells have been found to harbor the virus, even in the presence of antiretroviral therapy (ART) potentially promoting viral dissemination. While HIV-infected individuals often present with thrombocytopenia, they have also been reported to have increased platelet activation, as measured by an upregulation of expression of CD62P (P-selectin), CD40 ligand, glycoprotein IV, and RANTES. Despite ART-mediated viral suppression, HIV-infected individuals reportedly have sustained platelet activation and dysfunction. This, in turn, contributes to persistent immune activation and an inflammatory vascular environment, seemingly involving neutrophil-platelet-endothelium interactions that increase the risk for development of comorbidities such as cardiovascular disease (CVD) that has become the leading cause of morbidity and mortality in HIV-infected individuals on treatment, clearly underscoring the importance of unraveling the possible etiologic roles of ARVs. In this context, abacavir and ritonavir-boosted lopinavir and darunavir have all been linked to an increased risk of CVD. This narrative review is therefore focused primarily on the role of neutrophils and platelets in HIV transmission and disease, as well as on the effect of HIV and the most common ARVs on the numbers and functions of these cells, including neutrophil-platelet-endothelial interactions.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Plaquetas/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV/patogenicidade , Neutrófilos/efeitos dos fármacos , Animais , Plaquetas/imunologia , Plaquetas/metabolismo , Plaquetas/virologia , HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Interações Hospedeiro-Patógeno , Humanos , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/virologia , Ativação Plaquetária/efeitos dos fármacos , Resultado do Tratamento
18.
J Infect Dis ; 224(4): 673-678, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-33373447

RESUMO

This multicountry prospective study investigated whether persistent systemic inflammation, measured by 8 plasma biomarkers, in HIV-1-infected Africans during suppressive antiretroviral therapy (ART) (viral load <50 copies/mL), was associated with CD4+ T-cell recovery and viral rebound (>1000 copies/mL) during long-term treatment. On-ART sCD14 and C-reactive protein concentrations were inversely associated with subsequent CD4+ T-cell counts. Risk of viral rebound was increased for participants with higher on-ART CXCL10 concentrations and reduced for those with a greater sCD163 decline during the first year of ART. Persistent systemic inflammation predicted CD4+ T-cell recovery and viral rebound, warranting further mechanistic research in relation to clinical outcomes.


Assuntos
Fármacos Anti-HIV , Linfócitos T CD4-Positivos , Infecções por HIV , Soropositividade para HIV , Fármacos Anti-HIV/uso terapêutico , Biomarcadores , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV/tratamento farmacológico , HIV-1 , Humanos , Inflamação/tratamento farmacológico , Estudos Prospectivos , Carga Viral
19.
J Empir Res Hum Res Ethics ; 15(5): 478-493, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32917117

RESUMO

Retraction of research articles is increasing but the reasons and characteristics of retractions involving authors from Africa have not been studied. Using records from the Retraction Watch database, we analyzed information on articles retracted between 2014 and 2018 with at least one author or co-author affiliated with an institution in the African region to determine the most prevalent types of misconduct, subject fields, and the characteristics of researchers or research teams associated with retraction. Plagiarism was the most frequent form of misconduct, followed by duplication. International collaboration was associated with fewer retractions for plagiarism and errors in data, but increased retractions due to authorship issues. Teams with at least one senior member were associated with fewer retractions due to plagiarism but more due to duplication of articles. We conclude by making recommendations for best practice, further research, and highlighting implications for education.


Assuntos
Pesquisa Biomédica , Má Conduta Científica , Autoria , Bases de Dados Factuais , Humanos , Plágio
20.
PLoS One ; 15(1): e0228218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945145

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0224723.].

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