Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Cell ; 187(5): 1238-1254.e14, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38367616

RESUMEN

CD4+ T cells with latent HIV-1 infection persist despite treatment with antiretroviral agents and represent the main barrier to a cure of HIV-1 infection. Pharmacological disruption of viral latency may expose HIV-1-infected cells to host immune activity, but the clinical efficacy of latency-reversing agents for reducing HIV-1 persistence remains to be proven. Here, we show in a randomized-controlled human clinical trial that the histone deacetylase inhibitor panobinostat, when administered in combination with pegylated interferon-α2a, induces a structural transformation of the HIV-1 reservoir cell pool, characterized by a disproportionate overrepresentation of HIV-1 proviruses integrated in ZNF genes and in chromatin regions with reduced H3K27ac marks, the molecular target sites for panobinostat. By contrast, proviruses near H3K27ac marks were actively selected against, likely due to increased susceptibility to panobinostat. These data suggest that latency-reversing treatment can increase the immunological vulnerability of HIV-1 reservoir cells and accelerate the selection of epigenetically privileged HIV-1 proviruses.


Asunto(s)
Infecciones por VIH , VIH-1 , Inhibidores de Histona Desacetilasas , Interferón-alfa , Panobinostat , Provirus , Humanos , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Panobinostat/uso terapéutico , Provirus/efectos de los fármacos , Latencia del Virus , Inhibidores de Histona Desacetilasas/uso terapéutico , Interferón-alfa/uso terapéutico
2.
Cell ; 185(2): 266-282.e15, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-35026153

RESUMEN

HIV-1-infected cells that persist despite antiretroviral therapy (ART) are frequently considered "transcriptionally silent," but active viral gene expression may occur in some cells, challenging the concept of viral latency. Applying an assay for profiling the transcriptional activity and the chromosomal locations of individual proviruses, we describe a global genomic and epigenetic map of transcriptionally active and silent proviral species and evaluate their longitudinal evolution in persons receiving suppressive ART. Using genome-wide epigenetic reference data, we show that proviral transcriptional activity is associated with activating epigenetic chromatin features in linear proximity of integration sites and in their inter- and intrachromosomal contact regions. Transcriptionally active proviruses were actively selected against during prolonged ART; however, this pattern was violated by large clones of virally infected cells that may outcompete negative selection forces through elevated intrinsic proliferative activity. Our results suggest that transcriptionally active proviruses are dynamically evolving under selection pressure by host factors.


Asunto(s)
VIH-1/genética , Provirus/genética , Transcripción Genética , Anciano , Secuencia de Bases , Evolución Biológica , Cromatina/metabolismo , Células Clonales , ADN Viral/genética , Epigénesis Genética/efectos de los fármacos , Femenino , Humanos , Ionomicina/farmacología , Masculino , Persona de Mediana Edad , Filogenia , Provirus/efectos de los fármacos , ARN Viral/genética , Acetato de Tetradecanoilforbol/farmacología , Transcripción Genética/efectos de los fármacos , Integración Viral/genética , Latencia del Virus/efectos de los fármacos , Latencia del Virus/genética
3.
Nature ; 614(7947): 309-317, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36599977

RESUMEN

Human immunodeficiency virus 1 (HIV-1) reservoir cells persist lifelong despite antiretroviral treatment1,2 but may be vulnerable to host immune responses that could be exploited in strategies to cure HIV-1. Here we used a single-cell, next-generation sequencing approach for the direct ex vivo phenotypic profiling of individual HIV-1-infected memory CD4+ T cells from peripheral blood and lymph nodes of people living with HIV-1 and receiving antiretroviral treatment for approximately 10 years. We demonstrate that in peripheral blood, cells harbouring genome-intact proviruses and large clones of virally infected cells frequently express ensemble signatures of surface markers conferring increased resistance to immune-mediated killing by cytotoxic T and natural killer cells, paired with elevated levels of expression of immune checkpoint markers likely to limit proviral gene transcription; this phenotypic profile might reduce HIV-1 reservoir cell exposure to and killing by cellular host immune responses. Viral reservoir cells harbouring intact HIV-1 from lymph nodes exhibited a phenotypic signature primarily characterized by upregulation of surface markers promoting cell survival, including CD44, CD28, CD127 and the IL-21 receptor. Together, these results suggest compartmentalized phenotypic signatures of immune selection in HIV-1 reservoir cells, implying that only small subsets of infected cells with optimal adaptation to their anatomical immune microenvironment are able to survive during long-term antiretroviral treatment. The identification of phenotypic markers distinguishing viral reservoir cells may inform future approaches for strategies to cure and eradicate HIV-1.


Asunto(s)
Linfocitos T CD4-Positivos , Infecciones por VIH , VIH-1 , Fenotipo , Latencia del Virus , Humanos , Antirretrovirales/farmacología , Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/genética , VIH-1/inmunología , VIH-1/aislamiento & purificación , Provirus/efectos de los fármacos , Provirus/genética , Provirus/aislamiento & purificación , Carga Viral , Latencia del Virus/efectos de los fármacos , Memoria Inmunológica , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Supervivencia Celular , Antígenos CD28 , Receptores de Interleucina-21
4.
Immunity ; 48(6): 1183-1194.e5, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29802019

RESUMEN

HIV-1 infection of CD4+ T cells leads to cytopathic effects and cell demise, which is counter to the observation that certain HIV-1-infected cells possess a remarkable long-term stability and can persist lifelong in infected individuals treated with suppressive antiretroviral therapy (ART). Using quantitative mass spectrometry-based proteomics, we showed that HIV-1 infection activated cellular survival programs that were governed by BIRC5, a molecular inhibitor of cell apoptosis that is frequently overexpressed in malignant cells. BIRC5 and its upstream regulator OX40 were upregulated in productively and latently infected CD4+ T cells and were functionally involved in maintaining their viability. Moreover, OX40-expressing CD4+ T cells from ART-treated patients were enriched for clonally expanded HIV-1 sequences, and pharmacological inhibition of BIRC5 resulted in a selective decrease of HIV-1-infected cells in vitro. Together, these findings suggest that BIRC5 supports long-term survival of HIV-1-infected cells and may lead to clinical strategies to reduce persisting viral reservoirs.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Survivin/metabolismo , Latencia del Virus/fisiología , Adulto , Anciano , Apoptosis , Supervivencia Celular/fisiología , Femenino , Infecciones por VIH/metabolismo , Infecciones por VIH/virología , VIH-1 , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
5.
Nature ; 585(7824): 261-267, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32848246

RESUMEN

Sustained, drug-free control of HIV-1 replication is naturally achieved in less than 0.5% of infected individuals (here termed 'elite controllers'), despite the presence of a replication-competent viral reservoir1. Inducing such an ability to spontaneously maintain undetectable plasma viraemia is a major objective of HIV-1 cure research, but the characteristics of proviral reservoirs in elite controllers remain to be determined. Here, using next-generation sequencing of near-full-length single HIV-1 genomes and corresponding chromosomal integration sites, we show that the proviral reservoirs of elite controllers frequently consist of oligoclonal to near-monoclonal clusters of intact proviral sequences. In contrast to individuals treated with long-term antiretroviral therapy, intact proviral sequences from elite controllers were integrated at highly distinct sites in the human genome and were preferentially located in centromeric satellite DNA or in Krüppel-associated box domain-containing zinc finger genes on chromosome 19, both of which are associated with heterochromatin features. Moreover, the integration sites of intact proviral sequences from elite controllers showed an increased distance to transcriptional start sites and accessible chromatin of the host genome and were enriched in repressive chromatin marks. These data suggest that a distinct configuration of the proviral reservoir represents a structural correlate of natural viral control, and that the quality, rather than the quantity, of viral reservoirs can be an important distinguishing feature for a functional cure of HIV-1 infection. Moreover, in one elite controller, we were unable to detect intact proviral sequences despite analysing more than 1.5 billion peripheral blood mononuclear cells, which raises the possibility that a sterilizing cure of HIV-1 infection, which has previously been observed only following allogeneic haematopoietic stem cell transplantation2,3, may be feasible in rare instances.


Asunto(s)
Silenciador del Gen , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Heterocromatina/genética , Provirus/genética , Integración Viral/genética , Latencia del Virus/genética , Adulto , Anciano , Centrómero/genética , Cromosomas Humanos Par 19/genética , ADN Satélite/genética , Femenino , Genoma Viral/genética , Infecciones por VIH/sangre , VIH-1/aislamiento & purificación , Heterocromatina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Provirus/aislamiento & purificación , Proteínas Represoras/genética , Sitio de Iniciación de la Transcripción
6.
Trends Immunol ; 43(8): 608-616, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35905706

RESUMEN

With more than 38 million people living with HIV-1 (PLWH) worldwide, developing a cure for HIV-1 remains a major global health priority. Lifelong persistence of HIV-1 is frequently attributed to a pool of stable, transcriptionally silent HIV-1 proviruses, which are unaffected by currently available antiretroviral therapy (ART) or host immune activity. In this opinion article, we propose a more dynamic interpretation of HIV-1 reservoir cell biology and argue that HIV-1 proviruses frequently display residual viral transcriptional activity, making them vulnerable to longitudinal immune-mediated selection processes. Such mechanisms may, over extended periods of ART, induce an attenuated viral reservoir profile characterized by intact proviruses preferentially integrated into heterochromatin locations. We suggest that intensifying and accelerating naturally occurring selection mechanisms might represent a promising strategy for finding a potential cure for HIV-1 infection.


Asunto(s)
Infecciones por VIH , VIH-1 , Linfocitos T CD4-Positivos , Infecciones por VIH/tratamiento farmacológico , Humanos , Provirus , Latencia del Virus
7.
J Infect Dis ; 228(3): 281-286, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37201510

RESUMEN

Immune mechanisms that modulate human immunodeficiency virus-1 (HIV-1) reservoir size in neonates are poorly understood. Using samples from neonates who initiated antiretroviral therapy shortly after birth, we demonstrate that interleukin-8-secreting CD4 T cells, which are selectively expanded in early infancy, are more resistant to HIV-1 infection and inversely correlated with the frequency of intact proviruses at birth. Moreover, newborns with HIV-1 infection displayed a distinct B-cell profile at birth, with reduction of memory B cells and expansion of plasmablasts and transitional B cells; however, B-cell immune perturbations were unrelated to HIV-1 reservoir size and normalized after initiation of antiretroviral therapy. Clinical Trials Registration. NCT02369406.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Recién Nacido , Antirretrovirales/uso terapéutico , Provirus , Linfocitos T CD4-Positivos , Carga Viral
8.
Biochem Biophys Res Commun ; 686: 149182, 2023 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-37922575

RESUMEN

The specification of endoderm cells to prospective hepatoblasts is the starting point for hepatogenesis. However, how a prospective hepatoblast gains the hepatic fate remains elusive. Previous studies have shown that loss-of-function of either hhex or prox1a alone causes a small liver phenotype but without abolishing the hepatocyte differentiation, suggesting that absence of either Hhex or Prox1a alone is not sufficient to block the hepatoblast differentiation. Here, via genetic studies of the zebrafish two single (hhex-/- and prox1a-/-) and one double (hhex-/-prox1a-/-) mutants, we show that simultaneous loss-of-function of the hhex and prox1a two genes does not block the endoderm cells to gain the hepatoblast potency but abolishes the hepatic differentiation from the prospective hepatoblast. Consequently, the hhex-/-prox1a-/- double mutant displays a liverless phenotype that cannot be rescued by the injection of bmp2a mRNA. Taken together, we provide strong evidences showing that Hhex teams with Prox1a to act as a master control of the differentiation of the prospective hepatoblasts towards hepatocytes.


Asunto(s)
Hígado , Pez Cebra , Animales , Diferenciación Celular/genética , Hepatocitos , Estudios Prospectivos , Proteínas Represoras , Pez Cebra/genética , Proteínas de Pez Cebra/genética
9.
J Med Virol ; 95(1): e28425, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36562411

RESUMEN

Development of biomarkers for predicting the occurrence of hepatitis E virus related-acute liver failure (HEV-ALF) is conducive to prevention and early intervention. Serum samples from 250 HEV-ALF patients, 250 patients with acute hepatitis E (AHE) and 250 health controls (HCs) were collected. We assessed the predictive ability of extracellular vesicle (EV)-derived argininosuccinate synthase 1 (ASS1) levels for HEV-ALF occurrence. Serum EVs were successfully isolated. EV-derived ASS1 levels in the HEV-ALF patients were significantly higher than those in the AHE patients and HCs. In HEV-ALF patients, EV-derived ASS1 levels were positively correlated with the number of failed organs and disease progression. The logistical regression showed that EV-derived ASS1 level is an independent risk factor for HEV-ALF, and orthogonal partial least squares discriminant analysis (OPLS-DA) also suggested that EV-derived ASS1 level has high predictive capability. Besides, the area under the curve (AUC) of EV-derived ASS1 level to predict HEV-ALF occurrence was 0.728 (0.684-0.772) with the sensitivity and specificity being 72.80% and 64.80%, which had a high decision-making ability. Furthermore, there existed no significant difference between the age ≥60 and age <60 groups in EV-derived ASS1 levels. Serum EV-derived ASS1 level is a promising predictor for the occurrence of HEV-ALF.


Asunto(s)
Vesículas Extracelulares , Virus de la Hepatitis E , Hepatitis E , Fallo Hepático Agudo , Humanos , Argininosuccinato Sintasa , Hepatitis E/diagnóstico , Hepatitis E/epidemiología
10.
Anal Biochem ; 671: 115154, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37100107

RESUMEN

Dopamine (DA) and Fe3+ as the important bioactive ingredients, playing an indispensable role in human metabolism. Therefore, developing the accurate detection of DA and Fe3+ is of great significance for disease screening. Herein, we put forward a simple, rapid, and sensitive fluorescent detection strategy for the detection of dopamine and Fe3+ based on Rhodamine B-modified MOF-808 (RhB@MOF-808). RhB@MOF-808 produced strong fluorescence at 580 nm, and the fluorescence was significantly quenched after DA or Fe3+ was added, which was regarded as a static quenching process. Detection limits are as low as 60.25 nM and 48.34 nM, respectively. Furthermore, based on the responses of DA and Fe3+ to the probe, molecular logic gates were successfully designed. More importantly, RhB@MOF-808 had excellent cell membrane permeability and had been successfully used to label DA and Fe3+ in Hela cells, which presented a potential biological application value as a fluorescent probe for detecting DA and Fe3+.


Asunto(s)
Dopamina , Colorantes Fluorescentes , Humanos , Células HeLa , Límite de Detección
11.
Ann Intern Med ; 175(1): 95-100, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34781719

RESUMEN

BACKGROUND: A sterilizing cure of HIV-1 infection has been reported in 2 persons living with HIV-1 who underwent allogeneic hematopoietic stem cell transplantations from donors who were homozygous for the CCR5Δ32 gene polymorphism. However, this has been considered elusive during natural infection. OBJECTIVE: To evaluate persistent HIV-1 reservoir cells in an elite controller with undetectable HIV-1 viremia for more than 8 years in the absence of antiretroviral therapy. DESIGN: Detailed investigation of virologic and immunologic characteristics. SETTING: Tertiary care centers in Buenos Aires, Argentina, and Boston, Massachusetts. PATIENT: A patient with HIV-1 infection and durable drug-free suppression of HIV-1 replication. MEASUREMENTS: Analysis of genome-intact and replication-competent HIV-1 using near-full-length individual proviral sequencing and viral outgrowth assays, respectively; analysis of HIV-1 plasma RNA by ultrasensitive HIV-1 viral load testing. RESULTS: No genome-intact HIV-1 proviruses were detected in analysis of a total of 1.188 billion peripheral blood mononuclear cells and 503 million mononuclear cells from placental tissues. Seven defective proviruses, some of them derived from clonally expanded cells, were detected. A viral outgrowth assay failed to retrieve replication-competent HIV-1 from 150 million resting CD4+ T cells. No HIV-1 RNA was detected in 4.5 mL of plasma. LIMITATIONS: Absence of evidence for intact HIV-1 proviruses in large numbers of cells is not evidence of absence of intact HIV-1 proviruses. A sterilizing cure of HIV-1 can never be empirically proved. CONCLUSION: Genome-intact and replication-competent HIV-1 were not detected in an elite controller despite analysis of massive numbers of cells from blood and tissues, suggesting that this patient may have naturally achieved a sterilizing cure of HIV-1 infection. These observations raise the possibility that a sterilizing cure may be an extremely rare but possible outcome of HIV-1 infection. PRIMARY FUNDING SOURCE: National Institutes of Health and Bill & Melinda Gates Foundation.


Asunto(s)
Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/genética , Receptores CCR5/genética , Adulto , Argentina , Linfocitos T CD4-Positivos/inmunología , Femenino , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno , Humanos , Massachusetts , Embarazo , Resultado del Embarazo , Provirus/genética , Provirus/inmunología , Carga Viral , Viremia/virología , Replicación Viral/inmunología
12.
Neurochem Res ; 47(2): 264-278, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34468932

RESUMEN

Further understanding the mechanism for microglia activation is necessary for developing novel anti-inflammatory strategies. Our previous study found that the activation of sigma-1 receptor can effectively inhibit the neuroinflammation, independent of the canonical mechanisms, such as NF-κB, JNK and ERK inflammatory pathways. Thus, it is reasonable that an un-identified, non-canonical pathway contributes to the activation of microglia. In the present study, we found that a sigma-1 receptor agonist of 2-morpholin-4-ylethyl 1-phenylcyclohexane-1-carboxylate (PRE-084) suppressed lipopolysaccharide (LPS) elevated nitric oxide (NO) content in BV-2 microglia culture supernatant and LPS-raised mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), inducible nitric oxide synthase (iNOS) in BV-2 microglia. Moreover, PRE-084 alleviated LPS-increased Ser 9 de-phosphorylation of glycogen synthase kinase-3 beta (GSK-3ß), LPS-elevated catalytic activity of calcineurin, and LPS-raised percent and frequency of Ca2+ oscillatory BV-2 cells. We further found that the inhibitory effect of PRE-084 was reversed by a calcineurin activator of chlorogenic acid and a GSK-3ß activator of pyrvinium. Moreover, an IP3 receptor inhibitor of 2-aminoethoxydiphenyl borate mimicked the anti-inflammatory activity of PRE-084. Thus, we identified a noncanonical pro-neuroinflammary pathway of Ca2+ oscillation/Calcineurin/GSK-3ß and the inhibition of this pathway is necessary for the anti-inflammatory activity of sigma-1 receptor activation.


Asunto(s)
Calcineurina , Microglía , Antiinflamatorios/farmacología , Calcineurina/metabolismo , Línea Celular , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Lipopolisacáridos/farmacología , Microglía/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Receptores sigma , Factor de Necrosis Tumoral alfa/metabolismo , Receptor Sigma-1
13.
J Infect Dis ; 224(5): 777-782, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34467988

RESUMEN

We analyzed plasma levels of interferons (IFNs) and cytokines, and expression of IFN-stimulated genes in peripheral blood mononuclear cells in patients with coronavirus disease 2019 of varying disease severity. Patients hospitalized with mild disease exhibited transient type I IFN responses, while intensive care unit patients had prolonged type I IFN responses. Type II IFN responses were compromised in intensive care unit patients. Type III IFN responses were induced in the early phase of infection, even in convalescent patients. These results highlight the importance of early type I and III IFN responses in controlling coronavirus disease 2019 progression.


Asunto(s)
COVID-19/inmunología , Interferón Tipo I/inmunología , Interferón gamma/inmunología , Interferones/inmunología , COVID-19/sangre , Quimiocinas/sangre , Citocinas/sangre , Humanos , Interferón Tipo I/sangre , Interferón Tipo I/genética , Interferón gamma/sangre , Interferón gamma/genética , Interferones/sangre , Leucocitos Mononucleares/inmunología , SARS-CoV-2/aislamiento & purificación , Interferón lambda
14.
Brain Behav Immun ; 94: 225-234, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33607235

RESUMEN

A growing body of studies indicated that exosomes are one of vital players in pathological process of neuropsychiatric diseases, but their role in major depressive disorder (MDD) remains poorly understood. Here we purified plasma exosomes from depression including lipopolysaccharide (LPS)-challenged depression, chronic restraint stress (CRS)-induced depression, MDD subjects, and from control mice or volunteers. The therapeutic effect of these exogenous exosomes was assessed utilizing behavioral tests and biochemical approaches in the LPS-caused depression or microglial BV2 cells. The expression of exosomal sigma-1 receptor (Sig-1R) was evaluated by western blotting. The role of Sig-1R in the biological function of exosomes was determined using Sig-1R knockout mice and HEK 293 cells. Our results revealed that injection of exosomes from depression models or patients rather than normal controls significantly ameliorated depressive-like behaviors, deficiency of BDNF expression and neuro-inflammation in LPS-challenged mice. In addition, co-culture with exosomes from depression models or patients instead of from controls prevented LPS-induced inflammation responses in microglial BV2 cells. Moreover, Sig-1R was demonstrated for the first time to significantly be enriched in exosomes from depression models or patients compared with that from normal controls. However, Sig-1R null exosomes no longer emerged antidepressant-like action in LPS-challenged mice. Thus, we demonstrated that plasma exosomes from depression exerted antidepressant-like effects in a Sig-1R dependent manner in the LPS-induced depression. This work improves our understanding of the exosomes in depression, suggesting a novel exosomes-based approach for MDD treatment.


Asunto(s)
Trastorno Depresivo Mayor , Exosomas , Animales , Depresión , Células HEK293 , Humanos , Inflamación , Ratones , Receptores sigma , Receptor Sigma-1
15.
J Infect Dis ; 222(4): 655-660, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32236405

RESUMEN

The majority of cells with latent human immunodeficiency virus 1 infection are located in lymphoid tissues that are difficult to access. In the current study, we used single-genome near-full-length proviral sequencing to evaluate intact and defective proviruses in blood and lymph node CD4 T cells enriched for specific functional polarizations. We observed minor variations between the frequencies of proviral sequences within individual CD4 T-cell subsets and across tissue compartments. However, we noted multiple clonal clusters of identical intact or defective proviral sequences from distinct compartments and CD4 T-cell subpopulations, suggesting frequent interchanges between viral reservoir cells in blood and tissues.


Asunto(s)
Linfocitos T CD4-Positivos/virología , Infecciones por VIH/sangre , VIH-1/genética , Ganglios Linfáticos/virología , Provirus/genética , Subgrupos de Linfocitos T/virología , Antirretrovirales/uso terapéutico , Secuencia de Bases , ADN Viral/sangre , Infecciones por VIH/tratamiento farmacológico , Humanos , Carga Viral
16.
Glia ; 68(11): 2415-2426, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32460411

RESUMEN

Despite sigma-1 receptor (Sig-1R) is a promising therapeutic target in depression, little is known regarding the cellular mechanisms underlying its antidepressant responses. Here, we demonstrated that astrocyte can be a direct cellular target of Sig-1R exerting antidepressant-like effect. In multiple behavioral models including forced swimming test (FST), tail suspension test (TST), open field test (OFT), and chronic unpredictable mild stress (CUMS), inhibition of astrocyte function blocked pharmacological Sig-1R activation-induced antidepressant-like effect, while specific activation of astrocytc Sig-1R by adeno-associated virus (AAV) was sufficient to produce antidepressant-like effect. In depression-related cellular tests, Sig-1R agonist or lentivirus-stimulated astrocyte conditioned medium (ACM) promoted neuronal neurite outgrowth, dendritic branch, and survival. Mechanismly, stimulation of Sig-1R enhanced the expression of CD38 via activation of extracellular regulated protein kinases 1/2 (ERK1/2), resulting in facilitating mitochondrial transfer from astrocyte. Furthermore, blockage of CD38-driven astrocyte transferring mitochondria in vivo and in vitro reversed the antidepressant-like effect of pharmacological Sig-1R activation. Thus, this study sheds light on the cellular mechanism of Sig-1R activation producing antidepressant-like effect. These data present the first evidence that enhancement of Sig-1R action on astrocytes entirely exerts antidepressant-like effect, indicating that specific activation of astrocytic Sig-1R may provide a new approach for antidepressant drug development.


Asunto(s)
Astrocitos , Antidepresivos/farmacología , Mitocondrias , Receptores sigma , Receptor Sigma-1
17.
Gastroenterology ; 156(1): 187-202.e14, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30267710

RESUMEN

BACKGROUND & AIMS: Upon liver injury in which hepatocyte proliferation is compromised, liver progenitor cells (LPCs), derived from biliary epithelial cells (BECs), differentiate into hepatocytes. Little is known about the mechanisms of LPC differentiation. We used zebrafish and mouse models of liver injury to study the mechanisms. METHODS: We used transgenic zebrafish, Tg(fabp10a:CFP-NTR), to study the effects of compounds that alter epigenetic factors on BEC-mediated liver regeneration. We analyzed zebrafish with disruptions of the histone deacetylase 1 gene (hdac1) or exposed to MS-275 (an inhibitor of Hdac1, Hdac2, and Hdac3). We also analyzed zebrafish with mutations in sox9b, fbxw7, kdm1a, and notch3. Zebrafish larvae were collected and analyzed by whole-mount immunostaining and in situ hybridization; their liver tissues were collected for quantitative reverse transcription polymerase chain reaction. We studied mice in which hepatocyte-specific deletion of ß-catenin (Ctnnb1flox/flox mice injected with Adeno-associated virus serotype 8 [AAV8]-TBG-Cre) induces differentiation of LPCs into hepatocytes after a choline-deficient, ethionine-supplemented (CDE) diet. Liver tissues were collected and analyzed by immunohistochemistry and immunoblots. We performed immunohistochemical analyses of liver tissues from patients with compensated or decompensated cirrhosis or acute on chronic liver failure (n = 15). RESULTS: Loss of Hdac1 activity in zebrafish blocked differentiation of LPCs into hepatocytes by increasing levels of sox9b mRNA and reduced differentiation of LPCs into BECs by increasing levels of cdk8 mRNA, which encodes a negative regulator gene of Notch signaling. We identified Notch3 as the receptor that regulates differentiation of LPCs into BECs. Loss of activity of Kdm1a, a lysine demethylase that forms repressive complexes with Hdac1, produced the same defects in differentiation of LPCs into hepatocytes and BECs as observed in zebrafish with loss of Hdac1 activity. Administration of MS-275 to mice with hepatocyte-specific loss of ß-catenin impaired differentiation of LPCs into hepatocytes after the CDE diet. HDAC1 was expressed in reactive ducts and hepatocyte buds of liver tissues from patients with cirrhosis. CONCLUSIONS: Hdac1 regulates differentiation of LPCs into hepatocytes via Sox9b and differentiation of LPCs into BECs via Cdk8, Fbxw7, and Notch3 in zebrafish with severe hepatocyte loss. HDAC1 activity was also required for differentiation of LPCs into hepatocytes in mice with liver injury after the CDE diet. These pathways might be manipulated to induce LPC differentiation for treatment of patients with advanced liver diseases.


Asunto(s)
Conductos Biliares/enzimología , Diferenciación Celular , Proliferación Celular , Quinasa 8 Dependiente de Ciclina/metabolismo , Hepatocitos/enzimología , Histona Desacetilasa 1/metabolismo , Regeneración Hepática , Hígado/enzimología , Factor de Transcripción SOX9/metabolismo , Células Madre/enzimología , Proteínas de Pez Cebra/metabolismo , Insuficiencia Hepática Crónica Agudizada/enzimología , Insuficiencia Hepática Crónica Agudizada/patología , Animales , Conductos Biliares/patología , Deficiencia de Colina/genética , Deficiencia de Colina/metabolismo , Deficiencia de Colina/patología , Quinasa 8 Dependiente de Ciclina/genética , Modelos Animales de Enfermedad , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Hepatocitos/patología , Histona Desacetilasa 1/genética , Humanos , Hígado/patología , Cirrosis Hepática/enzimología , Cirrosis Hepática/patología , Ratones Noqueados , Mutación , Receptor Notch3/genética , Receptor Notch3/metabolismo , Factor de Transcripción SOX9/genética , Transducción de Señal , Células Madre/patología , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , beta Catenina/genética , beta Catenina/metabolismo
18.
Sensors (Basel) ; 21(1)2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33379344

RESUMEN

Target detection in hyperspectral imagery (HSI) aims at extracting target components of interest from hundreds of narrow contiguous spectral bands, where the prior target information plays a vital role. However, the limitation of the previous methods is that only single-layer detection is carried out, which is not sufficient to discriminate the target parts from complex background spectra accurately. In this paper, we introduce a hierarchical structure to the traditional algorithm matched filter (MF). Because of the advantages of MF in target separation performance, that is, the background components are suppressed while preserving the targets, the detection result of MF is used to further suppress the background components in a cyclic iterative manner. In each iteration, the average output of the previous iteration is used as a suppression criterion to distinguish these pixels judged as backgrounds in the current iteration. To better stand out the target spectra from the background clutter, HSI spectral input and the given target spectrum are whitened and then used to construct the MF in the current iteration. Finally, we provide the corresponding proofs for the convergence of the output and suppression criterion. Experimental results on three classical hyperspectral datasets confirm that the proposed method performs better than some traditional and recently proposed methods.

19.
PLoS Biol ; 14(9): e1002555, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27657329

RESUMEN

Digestive organ expansion factor (Def) is a nucleolar protein that plays dual functions: it serves as a component of the ribosomal small subunit processome for the biogenesis of ribosomes and also mediates p53 degradation through the cysteine proteinase calpain-3 (CAPN3). However, nothing is known about the exact relationship between Def and CAPN3 or the regulation of the Def function. In this report, we show that CAPN3 degrades p53 and its mutant proteins p53A138V, p53M237I, p53R248W, and p53R273P but not the p53R175H mutant protein. Importantly, we show that Def directly interacts with CAPN3 in the nucleoli and determines the nucleolar localisation of CAPN3, which is a prerequisite for the degradation of p53 in the nucleolus. Furthermore, we find that Def is modified by phosphorylation at five serine residues: S50, S58, S62, S87, and S92. We further show that simultaneous phosphorylations at S87 and S92 facilitate the nucleolar localisation of Capn3 that is not only essential for the degradation of p53 but is also important for regulating cell cycle progression. Hence, we propose that the Def-CAPN3 pathway serves as a nucleolar checkpoint for cell proliferation by selective inactivation of cell cycle-related substrates during organogenesis.

20.
Ann Plast Surg ; 82(4): 411-414, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30557181

RESUMEN

The current study introduces a novel approach of anterior mandible and mouth floor reconstruction with the myofascial iliac crest free flap. A series of 4 patients who presented between May 2015 and July 2017 had benefited from this technique. The myofascial component of this flap was designed to be attached to the iliac crest, and the flap was obtained after identifying the neurovascular pedicle. We transferred the iliac crest, with an outward-oriented placement, to the mandibular defect as the base of the alveolar process. We found that the iliac crest can provide sufficient bone height and an aesthetic shape for the reconstruction of the anterior mandible. More important, we also observed that the myofascial component on the flap surface completely replaced the oral mucosa in as early as 1 month after the operation. Moreover, the proper soft tissue volume can be achieved using this approach for better functional reconstruction of the oral mucosa. No obvious scar contracture of the myofascial component was observed during the follow-up period. The myofascial iliac crest free flap could provide a suitable reconstruction method for combined oral mucosa-mandible defects.


Asunto(s)
Trasplante Óseo/métodos , Colgajos Tisulares Libres/trasplante , Neoplasias Mandibulares/cirugía , Osteotomía Mandibular/métodos , Suelo de la Boca/cirugía , Procedimientos de Cirugía Plástica/métodos , Adulto , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Ilion/trasplante , Masculino , Neoplasias Mandibulares/patología , Microcirugia/métodos , Persona de Mediana Edad , Suelo de la Boca/patología , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Neoplasias de la Boca/cirugía , Recuperación de la Función , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA