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1.
J Virol ; 97(2): e0189022, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36688652

RESUMEN

Roseoloviruses (human herpesvirus 6A [HHV-6A], -6B, and -7) infect >90% of the human population during early childhood and are thought to remain latent or persistent throughout the life of the host. As such, these viruses are among the most pervasive and stealthy of all viruses; they must necessarily excel at escaping immune detection throughout the life of the host, and yet, very little is known about how these viruses so successfully escape host defenses. Here, we characterize the expression, trafficking, and posttranslational modifications of the HHV6B U20 gene product, which is encoded within a block of genes unique to the roseoloviruses. HHV-6B U20 trafficked slowly through the secretory system, receiving several posttranslational modifications to its N-linked glycans, indicative of surface-expressed glycoproteins, and eventually reaching the cell surface before being internalized. Interestingly, U20 is also phosphorylated on at least one Ser, Thr, or Tyr residue. These results provide a framework to understand the role(s) of U20 in evading host defenses. IMPORTANCE The roseolovirus U20 proteins are virus-encoded integral membrane glycoproteins possessing class I major histocompatibility complex (MHC)-like folds. Surprisingly, although U20 proteins from HHV-6A and -6B share 92% identity, recent studies ascribe different functions to HHV6A U20 and HHV6B U20. HHV6A U20 was shown to downregulate NKG2D ligands, while HHV6B U20 was shown to inhibit tumor necrosis factor alpha (TNF-α)-induced apoptosis during nonproductive infection with HHV6B (E. Kofod-Olsen, K. Ross-Hansen, M. H. Schleimann, D. K. Jensen, et al., J Virol 86:11483-11492, 2012, https://doi.org/10.1128/jvi.00847-12; A. E. Chaouat, B. Seliger, O. Mandelboim, D. Schmiedel, Front Immunol 12:714799, 2021, https://doi.org/10.3389/fimmu.2021.714799). Here, we have performed cell biological and biochemical characterization of the trafficking, glycosylation, and posttranslational modifications occurring on HHV6B U20.


Asunto(s)
Glicoproteínas de Membrana , Infecciones por Roseolovirus , Proteínas Virales , Humanos , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/inmunología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Infecciones por Roseolovirus/inmunología , Infecciones por Roseolovirus/virología , Proteínas Virales/genética , Proteínas Virales/inmunología , Evasión Inmune
2.
J Virol ; 95(14): e0162820, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-33952641

RESUMEN

Like all herpesviruses, the roseoloviruses (HHV6A, -6B, and -7) establish lifelong infection within their host, requiring these viruses to evade host antiviral responses. One common host-evasion strategy is the downregulation of host-encoded, surface-expressed glycoproteins. Roseoloviruses have been shown to evade the host immune response by downregulating NK-activating ligands, class I MHC, and the TCR/CD3 complex. To more globally identify glycoproteins that are differentially expressed on the surface of HHV6A-infected cells, we performed cell surface capture of N-linked glycoproteins present on the surface of T cells infected with HHV6A, and compared these to proteins present on the surface of uninfected T cells. We found that the protein tyrosine phosphatase CD45 is downregulated in T cells infected with HHV6A. We also demonstrated that CD45 is similarly downregulated in cells infected with HHV7. CD45 is essential for signaling through the T cell receptor and, as such, is necessary for developing a fully functional immune response. Interestingly, the closely related betaherpesviruses human cytomegalovirus (HCMV) and murine cytomegalovirus (MCMV) have also separately evolved unique mechanisms to target CD45. While HCMV and MCMV target CD45 signaling and trafficking, HHV6A acts to downregulate CD45 transcripts. IMPORTANCE Human herpesviruses-6 and -7 infect essentially 100% of the world's population before the age of 5 and then remain latent or persistent in their host throughout life. As such, these viruses are among the most pervasive and stealthy of all viruses. Host immune cells rely on the presence of surface-expressed proteins to identify and target virus-infected cells. Here, we investigated the changes that occur to proteins expressed on the cell surface of T cells after infection with human herpesvirus-6A. We discovered that HHV-6A infection results in a reduction of CD45 on the surface of infected T cells and impaired activation in response to T cell receptor stimulation.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Regulación Viral de la Expresión Génica , Herpesvirus Humano 6/genética , Herpesvirus Humano 7/genética , Antígenos Comunes de Leucocito/genética , Linfocitos T/virología , Línea Celular , Regulación hacia Abajo , Células HEK293 , Herpesvirus Humano 6/metabolismo , Herpesvirus Humano 7/metabolismo , Humanos , Estabilidad Proteica , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo
3.
Bioscience ; 72(9): 889-907, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36034512

RESUMEN

Long-term observations and experiments in diverse drylands reveal how ecosystems and services are responding to climate change. To develop generalities about climate change impacts at dryland sites, we compared broadscale patterns in climate and synthesized primary production responses among the eight terrestrial, nonforested sites of the United States Long-Term Ecological Research (US LTER) Network located in temperate (Southwest and Midwest) and polar (Arctic and Antarctic) regions. All sites experienced warming in recent decades, whereas drought varied regionally with multidecadal phases. Multiple years of wet or dry conditions had larger effects than single years on primary production. Droughts, floods, and wildfires altered resource availability and restructured plant communities, with greater impacts on primary production than warming alone. During severe regional droughts, air pollution from wildfire and dust events peaked. Studies at US LTER drylands over more than 40 years demonstrate reciprocal links and feedbacks among dryland ecosystems, climate-driven disturbance events, and climate change.

4.
J Immunol ; 205(1): 272-281, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32444392

RESUMEN

Acute graft-versus-host disease (GVHD) is a frequent complication of hematopoietic transplantation, yet patient risk stratification remains difficult, and prognostic biomarkers to guide early clinical interventions are lacking. We developed an approach to evaluate the potential of human T cells from hematopoietic grafts to produce GVHD. Nonconditioned NBSGW mice transplanted with titrated doses of human bone marrow developed GVHD that was characterized by widespread lymphocyte infiltration and organ pathology. Interestingly, GVHD was not an inevitable outcome in our system and was influenced by transplant dose, inflammatory status of the host, and type of graft. Mice that went on to develop GVHD showed signs of rapid proliferation in the human T cell population during the first 1-3 wk posttransplant and had elevated human IFN-γ in plasma that correlated negatively with the expansion of the human hematopoietic compartment. Furthermore, these early T cell activation metrics were predictive of GVHD onset 3-6 wk before phenotypic pathology. These results reveal an early window of susceptibility for pathological T cell activation following hematopoietic transplantation that is not simply determined by transient inflammation resulting from conditioning-associated damage and show that T cell parameters during this window can serve as prognostic biomarkers for risk of later GVHD development.


Asunto(s)
Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Linfocitos T/inmunología , Animales , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/inmunología , Humanos , Interferón gamma/sangre , Interferón gamma/inmunología , Activación de Linfocitos , Masculino , Ratones , Periodo Posoperatorio , Cultivo Primario de Células , Pronóstico , Factores de Tiempo , Quimera por Trasplante/inmunología , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Heterólogo/efectos adversos
5.
BMC Nephrol ; 23(1): 210, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35710381

RESUMEN

BACKGROUND: Atherosclerotic renovascular disease (ARVD) often follows an asymptomatic chronic course which may be undetected for many years. However, there are certain critical acute presentations associated with ARVD and these require a high index of suspicion for underlying high-grade RAS (renal artery stenosis) to improve patient outcomes. These acute presentations, which include decompensated heart failure syndromes, accelerated hypertension, rapidly declining renal function, and acute kidney injury (AKI), are usually associated with bilateral high-grade RAS (> 70% stenosis), or high-grade RAS in a solitary functioning kidney in which case the contralateral kidney is supplied by a vessel demonstrating renal artery occlusion (RAO). These presentations are typically underrepresented in large, randomized control trials which to date have been largely negative in terms of the conferred benefit of revascularization. CASE PRESENTATION: Here we describe 9 individual patients with 3 classical presentations including accelerated phase hypertension, heart failure syndromes, AKI and a fourth category of patients who suffered recurrent presentations. We describe their response to renal revascularization. The predominant presentation was that consistent with ischaemic nephropathy all of whom had a positive outcome with revascularization. CONCLUSION: A high index of suspicion is required for the diagnosis of RAS in these instances so that timely revascularization can be undertaken to restore or preserve renal function and reduce the incidence of hospital admissions for heart failure syndromes.


Asunto(s)
Lesión Renal Aguda , Aterosclerosis , Insuficiencia Cardíaca , Hipertensión Renovascular , Hipertensión , Placa Aterosclerótica , Obstrucción de la Arteria Renal , Lesión Renal Aguda/complicaciones , Aterosclerosis/complicaciones , Aterosclerosis/diagnóstico por imagen , Insuficiencia Cardíaca/complicaciones , Humanos , Hipertensión/complicaciones , Obstrucción de la Arteria Renal/complicaciones , Obstrucción de la Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/cirugía , Síndrome
6.
Pain Manag Nurs ; 21(2): 194-200, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31375420

RESUMEN

BACKGROUND: The intravenous administration of lidocaine for patients with chronic neuropathic pain is well documented in the literature. However, little is known about the role of the nurse caring for patients receiving the infusion. AIM: The purpose of this systematic review was to examine and describe common side effects associated with the intravenous administration of lidocaine to patients with chronic neuropathic pain and outline nursing care described in an effort to develop evidence-based protocols for care. METHOD: A comprehensive search of databases was completed and yielded eleven (n = 11) articles and one care protocol for analysis. RESULTS: Evidence was appraised and findings suggest intravenous lidocaine has a low risk of causing adverse events, however patients should be monitored closely. CONCLUSIONS: Nursing care focuses on pain assessment, close observation and intervention if neurological changes occur.


Asunto(s)
Lidocaína/administración & dosificación , Neuralgia/tratamiento farmacológico , Atención de Enfermería/normas , Administración Intravenosa , Anestésicos Locales/administración & dosificación , Anestésicos Locales/normas , Anestésicos Locales/uso terapéutico , Humanos , Lidocaína/normas , Lidocaína/uso terapéutico
7.
Arch Sex Behav ; 48(6): 1829-1845, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30874976

RESUMEN

Majority of college students hook up at least once during their time in school. The literature on casual sex encounters among college students is growing, though most studies are cross-sectional and individual studies focus on few outcomes at a time, leaving piecemeal and mixed results. The current longitudinal study clarifies prior work by analyzing how post-event process (PEP), an understudied construct within the hookup literature, and emotional (i.e., positive or negative) hookup reactions interact to predict a breadth of outcomes, representing holistic student well-being. The inclusion of PEP reframes the current literature to consider PEP as a predictor variable of hookup outcomes, as moderated by emotional hookup reactions. This is consistent with literature indicating emotional experiences affect PEP across a variety of incidents. Participants (N = 377, 87.6% female) completed self-report measures at 2-month intervals. We tested relationships between the main and interaction effects of PEP and emotional hookup reactions as a moderation regression analyses on anxiety, academic engagement, religious coping, and psychological flourishing. The main effect of PEP predicted more anxiety and less negative religious coping, negative hookup reactions predicted more anxiety, and positive hookup reactions predicted more flourishing. Regarding interaction effects, high levels of positive hookup reactions and PEP were associated with less anxiety, less academic engagement, more negative religious coping, and less psychological flourishing; high levels of negative hookup reactions and PEP were associated with less anxiety and more negative religious coping and were unrelated to academic engagement or flourishing over two months.


Asunto(s)
Conducta Sexual/psicología , Parejas Sexuales/psicología , Estudiantes/psicología , Emociones , Femenino , Humanos , Estudios Longitudinales , Masculino , Universidades
8.
PLoS Pathog ; 12(8): e1005868, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27580123

RESUMEN

The natural killer cell receptor NKG2D activates NK cells by engaging one of several ligands (NKG2DLs) belonging to either the MIC or ULBP families. Human cytomegalovirus (HCMV) UL16 and UL142 counteract this activation by retaining NKG2DLs and US18 and US20 act via lysomal degradation but the importance of NK cell evasion for infection is unknown. Since NKG2DLs are highly conserved in rhesus macaques, we characterized how NKG2DL interception by rhesus cytomegalovirus (RhCMV) impacts infection in vivo. Interestingly, RhCMV lacks homologs of UL16 and UL142 but instead employs Rh159, the homolog of UL148, to prevent NKG2DL surface expression. Rh159 resides in the endoplasmic reticulum and retains several NKG2DLs whereas UL148 does not interfere with NKG2DL expression. Deletion of Rh159 releases human and rhesus MIC proteins, but not ULBPs, from retention while increasing NK cell stimulation by infected cells. Importantly, RhCMV lacking Rh159 cannot infect CMV-naïve animals unless CD8+ cells, including NK cells, are depleted. However, infection can be rescued by replacing Rh159 with HCMV UL16 suggesting that Rh159 and UL16 perform similar functions in vivo. We therefore conclude that cytomegaloviral interference with NK cell activation is essential to establish but not to maintain chronic infection.


Asunto(s)
Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Evasión Inmune , Células Asesinas Naturales/inmunología , Activación de Linfocitos , Animales , Humanos , Células K562 , Macaca fascicularis , Glicoproteínas de Membrana/inmunología , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Proteínas Virales/inmunología
9.
Planta Med ; 84(9-10): 613-626, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29672820

RESUMEN

Use of herbal dietary supplements by the public is common and has been happening for centuries. In the United States, the Food and Drug Administration has a limited scope of regulation over marketed herbal dietary supplements, which may contain toxic botanical compounds that pose a public health risk. While the Food and Drug Administration has made efforts to prohibit the sale of unsafe herbal dietary supplements, numerous reports have proliferated of adverse events due to these supplements. This literature review investigates bioactive plant compounds commonly used in herbal dietary supplements and their relative toxicities. Using primarily the National Library of Medicine journal database and SciFinder for current reports, 47 toxic compounds in 55 species from 46 plant families were found to demonstrate harmful effects due to hepatic, cardiovascular, central nervous system, and digestive system toxicity. This review further contributes a novel and comprehensive view of toxicity across the botanical dietary market, and investigates the toxicity of the top ten botanical dietary supplements purchased in the United States of America to gauge the exposure risk of toxicity to the public. The criteria of measuring toxicity in this review (plant compound, family, quantity, and toxicity effects) across the entire market in the United States, with special attention to those supplements whose exposure to the consumer is maximal, provides a unique contribution to the investigation of botanical supplements.


Asunto(s)
Suplementos Dietéticos/efectos adversos , Preparaciones de Plantas/efectos adversos , Plantas/química , Animales , Humanos
10.
J Virol ; 88(6): 3298-308, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24390327

RESUMEN

UNLABELLED: The U21 gene product from human herpesvirus 7 binds to and redirects class I major histocompatibility complex (MHC) molecules to a lysosomal compartment. The molecular mechanism by which U21 reroutes class I MHC molecules to lysosomes is not known. Here, we have reconstituted the interaction between purified soluble U21 and class I MHC molecules, suggesting that U21 does not require additional cellular proteins to interact with class I MHC molecules. Our results demonstrate that U21, itself predicted to contain an MHC class I-like protein fold, interacts tightly with class I MHC molecules as a tetramer, in a 4:2 stoichiometry. These observations have helped to elucidate a refined model describing the mechanism by which U21 escorts class I MHC molecules to the lysosomal compartment. IMPORTANCE: In this report, we show that the human herpesvirus 7 (HHV-7) immunoevasin U21, itself a class I MHC-like protein, binds with high affinity to class I MHC molecules as a tetramer and escorts them to lysosomes, where they are degraded. While many class I MHC-like molecules have been described in detail, this unusual viral class I-like protein functions as a tetramer, associating with class I MHC molecules in a 4:2 ratio, illuminating a functional significance of homooligomerization of a class I MHC-like protein.


Asunto(s)
Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Herpesvirus Humano 7/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Infecciones por Roseolovirus/metabolismo , Infecciones por Roseolovirus/virología , Proteínas Virales/química , Proteínas Virales/metabolismo , Proteínas Portadoras/genética , Herpesvirus Humano 7/química , Herpesvirus Humano 7/genética , Humanos , Unión Proteica , Multimerización de Proteína , Proteínas Virales/genética
11.
Rural Remote Health ; 15(4): 3354, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26498673

RESUMEN

INTRODUCTION: Canada has the second highest per capita water consumption in the world. However, little is known about complex socio-economic and cultural dynamics of water insecurities in Indigenous communities and the multiple health consequences. Most studies have concentrated on a simplified interpretation of accessibility, availability and quality issues, including some common water-borne infections as the only health outcomes. Thus, several government initiatives on potable water supply, particularly for remotely located communities, have failed to sustain and promote a healthy lifestyle. The objective was to explore the water insecurity, coping strategies and associated health risks in a small and isolated sub-Arctic Indigenous (Inuit) community in Canada. METHODS: The study was based on a community-based survey (2013) in one of the most remote Inuit communities of Labrador. In-depth, open-ended key informant (KI) interviews (community leader (1), woman (1), nurse (1), teacher (1), and elder (1)) and focus group discussions (FGDs) were conducted with community leaders (5), community members (25), women (5), and high school students (8). Convenience sampling was followed in selection of the subjects for FGDs and approached some KIs. All the water sources (five in April and seven in October) were visited and tested for their physical, chemical and microbiological parameters. The FGDs and KI interviews were audio recorded and transcribed. In the analysis, the data (qualitative and quantitative) were broadly categorized into (a) water sources, access and quality, (b) coping, (c) health risks and (d) challenges to run a public water system. RESULTS: The community did not have any piped water supply. Their regular sources of water consisted of several unmonitored local streams, brooks, and ponds. The public water system was not affordable to the majority of community members who solely depended on government aid. Animal fecal contamination (in natural sources such as streams, brooks, and ponds) and the presence of disinfection by-products (in the public water system) were the major quality issues. Gastro-intestinal infections were the most common disease in the community. Per capita water consumption was less than one-third of the Canadian national average (274 L/day/person), severely compromising personal hygiene and water intake. High-sugar-content beverages were the most common alternative to lack of accessible and affordable potable water, particularly for children. Mental stress due to water insecurity and chronic back and shoulder injuries due to carrying heavy water buckets every day were the commonly encountered adverse health outcomes. CONCLUSIONS: Water insecurity has put the community at risk of multiple serious adverse health outcomes. The scenario is not unique in Canada. There are many remote Indigenous communities facing similar kinds of water insecurity.


Asunto(s)
Agua Potable/normas , Salud Ambiental/normas , Inuk , Contaminación del Agua/estadística & datos numéricos , Abastecimiento de Agua/métodos , Canadá , Agua Potable/microbiología , Salud Ambiental/tendencias , Femenino , Humanos , Masculino , Evaluación de Necesidades , Terranova y Labrador , Investigación Cualitativa , Características de la Residencia , Factores de Riesgo , Salud Rural , Factores Socioeconómicos , Encuestas y Cuestionarios , Poblaciones Vulnerables
12.
Front Immunol ; 15: 1363156, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38953028

RESUMEN

Introduction: Human Herpesvirus 6B (HHV-6B) impedes host immune responses by downregulating class I MHC molecules (MHC-I), hindering antigen presentation to CD8+ T cells. Downregulation of MHC-I disengages inhibitory receptors on natural killer (NK) cells, resulting in activation and killing of the target cell if NK cell activating receptors such as NKG2D have engaged stress ligands upregulated on the target cells. Previous work has shown that HHV-6B downregulates three MHC-like stress ligands MICB, ULBP1, and ULBP3, which are recognized by NKG2D. The U20 glycoprotein of the related virus HHV-6A has been implicated in the downregulation of ULBP1, but the precise mechanism remains undetermined. Methods: We set out to investigate the role of HHV-6B U20 in modulating NK cell activity. We used HHV-6B U20 expressed as a recombinant protein or transduced into target cells, as well as HHV-6B infection, to investigate binding interactions with NK cell ligands and receptors and to assess effects on NK cell activation. Small-angle X-ray scattering was used to align molecular models derived from machine-learning approaches. Results: We demonstrate that U20 binds directly to ULBP1 with sub-micromolar affinity. Transduction of U20 decreases NKG2D binding to ULBP1 at the cell surface but does not decrease ULBP1 protein levels, either at the cell surface or in toto. HHV-6B infection and soluble U20 have the same effect. Transduction of U20 blocks NK cell activation in response to cell-surface ULBP1. Structural modeling of the U20 - ULBP1 complex indicates some similarities to the m152-RAE1γ complex.


Asunto(s)
Proteínas Ligadas a GPI , Herpesvirus Humano 6 , Células Asesinas Naturales , Activación de Linfocitos , Subfamilia K de Receptores Similares a Lectina de Células NK , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Herpesvirus Humano 6/inmunología , Proteínas Ligadas a GPI/metabolismo , Proteínas Ligadas a GPI/inmunología , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Activación de Linfocitos/inmunología , Unión Proteica , Proteínas Virales/inmunología , Proteínas Virales/metabolismo , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Péptidos y Proteínas de Señalización Intracelular
13.
Natl Sci Rev ; 11(5): nwae163, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38855727

RESUMEN

China, one of the most populous countries in the world, has suffered the highest number of natural disaster-related deaths from fire. On local scales, the main causes of urban fires are anthropogenic in nature. Yet, on regional to national scales, little is known about the indicators of large-scale co-varying urban fire activity in China. Here, we present the China Fire History Atlas (CFHA), which is based on 19 947 documentary records and represents fires in urban areas of China over the twentieth century (1901-1994). We found that temperature variability is a key indicator of urban fire activity in China, with warmer temperatures being correlated with more urban fires, and that this fire-temperature relationship is seasonally and regionally explicit. In the early twentieth century, however, the fire-temperature relationship was overruled by war-related fires in large urban areas. We further used the fire-temperature relationship and multiple emissions scenarios to project fire activity across China into the twenty-first century. Our projections show a distinct increase in future urban fire activity and fire-related economic loss. Our findings provide insights into fire-climate relationships in China for densely-populated areas and on policy-relevant time scales and they contribute spatial coverage to efforts to improve global fire models.

14.
Cancer Immun ; 13: 9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23885215

RESUMEN

Invariant natural killer T (iNKT) cells are innate T lymphocytes that specifically recognize α-linked glycosphingolipids (α-GSLs) as antigens presented by CD1d molecules. Activating iNKT cells by administering α-GSLs improves disease outcomes in murine cancer models and, thus, there is great interest in the clinical potential of these lipids for treating human cancers. However, humans possess several other CD1 isoforms that are not present in mice and it is not clear whether these CD1 molecules, which also bind lipids, affect human iNKT cell responses. We demonstrate here that CD1c, which is co-expressed with CD1d on blood dendritic cells and on a fraction of B cells, is able to present α-galactosylceramide (α-GalCer) as a weak agonist to human iNKT cells, and that the presence of CD1c synergistically enhances α-GalCerdependent activation of iNKT cells by CD1d. Primary human B cells expressing CD1c induced stronger iNKT cell responses to α-GalCer than the CD1c- subset, and an antibody against CD1c inhibited iNKT cell cytokine secretion. These results suggest that therapeutic activation of human iNKT cells by α-GSLs will be driven preferentially by CD1c+ cell types. Thus, B cell neoplasias that co-express CD1c and CD1d may be particularly susceptible to α-GSL therapy, and cancer vaccines using α-GSLs as adjuvants may be most effective when presented by CD1c+ antigen-presenting cells.


Asunto(s)
Antígenos CD1/biosíntesis , Galactosilceramidas/inmunología , Glicoproteínas/biosíntesis , Células T Asesinas Naturales/inmunología , Secuencia de Aminoácidos , Animales , Antígenos CD1/inmunología , Antígenos CD1/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Células HeLa , Humanos , Activación de Linfocitos/inmunología , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica
15.
PLoS Pathog ; 7(11): e1002362, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22102813

RESUMEN

Herpesviruses have evolved numerous immune evasion strategies to facilitate establishment of lifelong persistent infections. Many herpesviruses encode gene products devoted to preventing viral antigen presentation as a means of escaping detection by cytotoxic T lymphocytes. The human herpesvirus-7 (HHV-7) U21 gene product, for example, is an immunoevasin that binds to class I major histocompatibility complex molecules and redirects them to the lysosomal compartment. Virus infection can also induce the upregulation of surface ligands that activate NK cells. Accordingly, the herpesviruses have evolved a diverse array of mechanisms to prevent NK cell engagement of NK-activating ligands on virus-infected cells. Here we demonstrate that the HHV-7 U21 gene product interferes with NK recognition. U21 can bind to the NK activating ligand ULBP1 and reroute it to the lysosomal compartment. In addition, U21 downregulates the surface expression of the NK activating ligands MICA and MICB, resulting in a reduction in NK-mediated cytotoxicity. These results suggest that this single viral protein may interfere both with CTL-mediated recognition through the downregulation of class I MHC molecules as well as NK-mediated recognition through downregulation of NK activating ligands.


Asunto(s)
Proteínas Portadoras/metabolismo , Citotoxicidad Inmunológica , Herpesvirus Humano 7/patogenicidad , Antígenos de Histocompatibilidad Clase I/metabolismo , Células Asesinas Naturales/inmunología , Proteínas Virales/metabolismo , Presentación de Antígeno , Línea Celular , Proteínas Ligadas a GPI/metabolismo , Células HEK293 , Herpesvirus Humano 7/inmunología , Herpesvirus Humano 7/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/virología , Lisosomas , Infecciones por Roseolovirus/inmunología , Proteínas Virales/inmunología
16.
J Med Entomol ; 60(6): 1221-1229, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37862060

RESUMEN

Orbiviruses are of significant importance to the health of wildlife and domestic animals worldwide; the major orbiviruses transmitted by multiple biting midge (Culicoides) species include bluetongue virus, epizootic hemorrhagic disease virus, and African horse sickness virus. The viruses, insect vectors, and hosts are anticipated to be impacted by global climate change, altering established Orbivirus epidemiology. Changes in global climate have the potential to alter the vector competence and extrinsic incubation period of certain biting midge species, affect local and long-distance dispersal dynamics, lead to range expansion in the geographic distribution of vector species, and increase transmission period duration (earlier spring onset and later fall transmission). If transmission intensity is associated with weather anomalies such as droughts and wind speeds, there may be changes in the number of outbreaks and periods between outbreaks for some regions. Warmer temperatures and changing climates may impact the viral genome by facilitating reassortment and through the emergence of novel viral mutations. As the climate changes, Orbivirus epidemiology will be inextricably altered as has been seen with recent outbreaks of bluetongue, epizootic hemorrhagic disease, and African horse sickness outside of endemic areas, and requires interdisciplinary teams and approaches to assess and mitigate future outbreak threats.


Asunto(s)
Virus de la Enfermedad Equina Africana , Enfermedad Equina Africana , Ceratopogonidae , Enfermedades de los Caballos , Orbivirus , Caballos , Animales , Enfermedad Equina Africana/epidemiología , Cambio Climático
17.
Sci Adv ; 9(12): eadf0567, 2023 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-36961891

RESUMEN

An important paradigm in allogeneic hematopoietic cell transplantations (allo-HCTs) is the prevention of graft-versus-host disease (GVHD) while preserving the graft-versus-leukemia (GVL) activity of donor T cells. From an observational clinical study of adult allo-HCT recipients, we identified a CD4+/CD8+ double-positive T cell (DPT) population, not present in starting grafts, whose presence was predictive of ≥ grade 2 GVHD. Using an established xenogeneic transplant model, we reveal that the DPT population develops from antigen-stimulated CD8 T cells, which become transcriptionally, metabolically, and phenotypically distinct from single-positive CD4 and CD8 T cells. Isolated DPTs were sufficient to mediate xeno-GVHD pathology when retransplanted into naïve mice but provided no survival benefit when mice were challenged with a human B-ALL cell line. Overall, this study reveals human DPTs as a T cell population directly involved with GVHD pathology.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Ratones , Animales , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos/patología
18.
Sleep ; 45(7)2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35460556

RESUMEN

Sleep disturbances are a common and unmet health problem in Latinx. While Latinx report similar sleep disturbances as non-Hispanic Whites [NHW], Latinx suffer from these disturbances to a greater degree than their NHW counterparts. Sleep disturbances are associated with increased risk of chronic health conditions, which Latinx experience at high rates. Research also points to significant sleep differences within Latinx. Given that Latinx are a rapidly growing population in the United States, sleep disparities between Latinx and NHWs and sleep differences within Latinx warrant further investigation. While research on Latinx sleep is growing, the last narrative review on US Latinx sleep health was published by Loredo and colleagues in 2010. Our narrative review expands on Loredo et al.'s work, adding the literature on Latinx sleep published since 2010 (N = 70). A total of 78 peer-reviewed articles related to young to middle-aged (i.e., 18-65 years) healthy Latinx adult sleep were identified in three databases-PsycInfo, PubMed/Medline, and Web of Science. With the socioecological model as framework, this review (1) summarizes current evidence pertaining to sleep health in healthy, community dwelling, urban Latinx adults; (2) discusses measurement challenges related to investigating Latinx sleep disparities and differences; and (3) discusses potential contributors to Latinx sleep. The prevalence of short sleep duration, long sleep duration, and poor sleep quality is high among Latinx; there are differences by Latinx subgroup. Our review identifies several multi-level influences associated with poor sleep: SES, sexual minority status, racial discrimination, access to care, neighborhood environment, and shift work. N = 250/250.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Adulto , Enfermedad Crónica , Etnicidad , Humanos , Persona de Mediana Edad , Sueño , Trastornos del Sueño-Vigilia/epidemiología , Estados Unidos/epidemiología , Población Blanca
19.
Front Immunol ; 13: 864898, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35444636

RESUMEN

Human roseolovirus U20 and U21 are type I membrane glycoproteins that have been implicated in immune evasion by interfering with recognition of classical and non-classical MHC proteins. U20 and U21 are predicted to be type I glycoproteins with extracytosolic immunoglobulin-like domains, but detailed structural information is lacking. AlphaFold and RoseTTAfold are next generation machine-learning-based prediction engines that recently have revolutionized the field of computational three-dimensional protein structure prediction. Here, we review the structural biology of viral immunoevasins and the current status of computational structure prediction algorithms. We use these computational tools to generate structural models for U20 and U21 proteins, which are predicted to adopt MHC-Ia-like folds with closed MHC platforms and immunoglobulin-like domains. We evaluate these structural models and place them within current understanding of the structural basis for viral immune evasion of T cell and natural killer cell recognition.


Asunto(s)
Herpesvirus Humano 6 , Herpesvirus Humano 7 , Infecciones por Roseolovirus , Herpesvirus Humano 6/metabolismo , Herpesvirus Humano 7/metabolismo , Humanos , Modelos Estructurales , Proteínas Virales/metabolismo
20.
Front Immunol ; 13: 936968, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35677042

RESUMEN

[This corrects the article DOI: 10.3389/fimmu.2022.864898.].

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