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1.
Nat Immunol ; 18(12): 1299-1309, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28967880

RESUMO

NLRX1 is unique among the nucleotide-binding-domain and leucine-rich-repeat (NLR) proteins in its mitochondrial localization and ability to negatively regulate antiviral innate immunity dependent on the adaptors MAVS and STING. However, some studies have suggested a positive regulatory role for NLRX1 in inducing antiviral responses. We found that NLRX1 exerted opposing regulatory effects on viral activation of the transcription factors IRF1 and IRF3, which might potentially explain such contradictory results. Whereas NLRX1 suppressed MAVS-mediated activation of IRF3, it conversely facilitated virus-induced increases in IRF1 expression and thereby enhanced control of viral infection. NLRX1 had a minimal effect on the transcription of IRF1 mediated by the transcription factor NF-kB and regulated the abundance of IRF1 post-transcriptionally by preventing translational shutdown mediated by the double-stranded RNA (dsRNA)-activated kinase PKR and thereby allowed virus-induced increases in the abundance of IRF1 protein.


Assuntos
Hepacivirus/imunologia , Hepatite C/imunologia , Imunidade Inata/imunologia , Fator Regulador 1 de Interferon/imunologia , Fator Regulador 3 de Interferon/imunologia , Proteínas Mitocondriais/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Células Cultivadas , Ativação Enzimática/imunologia , Células HEK293 , Hepatite C/virologia , Hepatócitos/imunologia , Hepatócitos/virologia , Humanos , Fator Regulador 1 de Interferon/metabolismo , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/genética , NF-kappa B/metabolismo , RNA Viral/genética , Vírus Sendai/imunologia , eIF-2 Quinase/metabolismo
2.
PLoS Pathog ; 18(8): e1010543, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35969644

RESUMO

Although picornaviruses are conventionally considered 'nonenveloped', members of multiple picornaviral genera are released nonlytically from infected cells in extracellular vesicles. The mechanisms underlying this process are poorly understood. Here, we describe interactions of the hepatitis A virus (HAV) capsid with components of host endosomal sorting complexes required for transport (ESCRT) that play an essential role in release. We show release of quasi-enveloped virus (eHAV) in exosome-like vesicles requires a conserved export signal located within the 8 kDa C-terminal VP1 pX extension that functions in a manner analogous to late domains of canonical enveloped viruses. Fusing pX to a self-assembling engineered protein nanocage (EPN-pX) resulted in its ESCRT-dependent release in extracellular vesicles. Mutational analysis identified a 24 amino acid peptide sequence located within the center of pX that was both necessary and sufficient for nanocage release. Deleting a YxxL motif within this sequence ablated eHAV release, resulting in virus accumulating intracellularly. The pX export signal is conserved in non-human hepatoviruses from a wide range of mammalian species, and functional in pX sequences from bat hepatoviruses when fused to the nanocage protein, suggesting these viruses are released as quasi-enveloped virions. Quantitative proteomics identified multiple ESCRT-related proteins associating with EPN-pX, including ALG2-interacting protein X (ALIX), and its paralog, tyrosine-protein phosphatase non-receptor type 23 (HD-PTP), a second Bro1 domain protein linked to sorting of ubiquitylated cargo into multivesicular endosomes. RNAi-mediated depletion of either Bro1 domain protein impeded eHAV release. Super-resolution fluorescence microscopy demonstrated colocalization of viral capsids with endogenous ALIX and HD-PTP. Co-immunoprecipitation assays using biotin-tagged peptides and recombinant proteins revealed pX interacts directly through the export signal with N-terminal Bro1 domains of both HD-PTP and ALIX. Our study identifies an exceptionally potent viral export signal mediating extracellular release of virus-sized protein assemblies and shows release requires non-redundant activities of both HD-PTP and ALIX.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Vírus da Hepatite A , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Vírus da Hepatite A/genética , Vírus da Hepatite A/metabolismo , Mamíferos , Proteínas Virais/metabolismo
3.
World J Urol ; 42(1): 72, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38324022

RESUMO

PURPOSE: Prostate cancer is one of the most common oncologic diseases. Outpatient robotic-assisted laparoscopic radical prostatectomy (RALP) has gained popularity due to its ability to minimize patient costs while maintaining low complication rates. Few studies have analyzed the possibility of performing outpatient RALP specifically in patients undergoing concurrent pelvic lymph node dissections (PLND). METHODS: Using the National Surgical Quality Improvement Program Database (NSQIP), we identified total number of RALP, stratified into inpatient and outpatient groups including those with and without PLND from 2016 to 2021. Baseline characteristics, intraoperative and postoperative complications, and unplanned readmission rates were summarized. Proportions of outpatient procedures were calculated to assess adoption of outpatient protocol. RESULTS: Between 2016 and 2021, a total of 58,527 RALP were performed, 3.7% (2142) outpatient and 96.3% inpatient. Altogether, patients undergoing outpatient RALP without PLND were more likely to have hypertension (52.6% vs. 46.3%, p < 0.01). Patients undergoing outpatient RALP without PLND were more likely to have sepsis or urinary tract infections (3.4% vs. 1.9%, p = 0.04) when compared to outpatient RALP with PLND. Cardiopulmonary, renal, thromboembolic complications, and 30-day events such as unplanned readmission, reoperation rates, and mortality were similar in both groups. However, among multivariate analysis regarding 30-day readmission and complications, there were no significant differences between outpatient RALP with or without PLND. CONCLUSION: Patients undergoing outpatient RALP without PLND were more likely to have baseline hypertension and higher rates of postoperative infection, when compared to outpatient RALP with PLND. No significant differences were seen regarding 30-day readmission or complications on multivariate analysis.


Assuntos
Hipertensão , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Masculino , Humanos , Estudos de Viabilidade , Alta do Paciente , Prostatectomia , Excisão de Linfonodo
4.
J Hepatol ; 78(2): 271-280, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36152761

RESUMO

BACKGROUND & AIMS: Consistent with its relatively narrow host species range, hepatitis A virus (HAV) cannot infect C57BL/6 mice. However, in Mavs-/- mice with genetic deficiency of the innate immune signaling adaptor MAVS, HAV replicates robustly in the absence of disease. The HAV 3ABC protease cleaves MAVS in human cells, thereby disrupting virus-induced IFN responses, but it cannot cleave murine MAVS (mMAVS) due to sequence differences at the site of scission. Here, we sought to elucidate the role of 3ABC MAVS cleavage in determining HAV pathogenesis and host species range. METHODS: Using CRISPR/Cas9 gene editing, we established two independent lineages of C57BL/6 mice with knock-in mutations altering two amino acids in mMAVS ('mMAVS-VS'), rendering it susceptible to 3ABC cleavage without loss of signaling function. We challenged homozygous Mavsvs/vs mice with HAV, and compared infection outcomes with C57BL/6 and genetically deficient Mavs-/- mice. RESULTS: The humanized murine mMAVS-VS protein was cleaved as efficiently as human MAVS when co-expressed with 3ABC in Huh-7 cells. In embyronic fibroblasts from Mavsvs/vs mice, mMAVS-VS was cleaved by ectopically expressed 3ABC, significantly disrupting Sendai virus-induced IFN responses. However, in contrast to Mavs-/- mice with genetic MAVS deficiency, HAV failed to establish infection in Mavsvs/vs mice, even with additional genetic knockout of Trif or Irf1. Nonetheless, when crossed with permissive Ifnar1-/- mice lacking type I IFN receptors, Mavsvs/vsIfnar1-/- mice demonstrated enhanced viral replication coupled with significant reductions in serum alanine aminotransferase, hepatocellular apoptosis, and intrahepatic inflammatory cell infiltrates compared with Ifnar1-/- mice. CONCLUSIONS: MAVS cleavage by 3ABC boosts viral replication and disrupts disease pathogenesis, but it is not by itself sufficient to break the host-species barrier to HAV infection in mice. IMPACT AND IMPLICATIONS: The limited host range of human hepatitis viruses could be explained by species-specific viral strategies that disrupt innate immune responses. Both hepatitis A virus (HAV) and hepatitis C virus express viral proteases that cleave the innate immune adaptor protein MAVS, in human but not mouse cells. However, the impact of this immune evasion strategy has never been assessed in vivo. Here we show that HAV 3ABC protease cleavage of MAVS enhances viral replication and lessens liver inflammation in mice lacking interferon receptors, but that it is insufficient by itself to overcome the cross-species barrier to infection in mice. These results enhance our understanding of how hepatitis viruses interact with the host and their impact on innate immune responses.


Assuntos
Vírus da Hepatite A , Hepatite A , Animais , Camundongos , Humanos , Vírus da Hepatite A/genética , Peptídeo Hidrolases , Camundongos Endogâmicos C57BL , Imunidade Inata , Proteases Virais
5.
J Virol ; 96(21): e0119522, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36286484

RESUMO

Hepatoviruses are atypical hepatotropic picornaviruses that are released from infected cells without lysis in small membranous vesicles. These exosome-like, quasi-enveloped virions (eHAV) are infectious and the only form of hepatitis A virus (HAV) found circulating in blood during acute infection. eHAV is released through multivesicular endosomes in a process dependent on endosomal sorting complexes required for transport (ESCRT). Capsid protein interactions with the ESCRT-associated Bro1 domain proteins, ALG-2-interacting protein X (ALIX) and His domain-containing protein tyrosine phosphatase (HD-PTP), which are both recruited to the pX domain of 1D (VP1pX), are critical for this process. Previous proteomics studies suggest pX also binds the HECT domain, NEDD4 family E3 ubiquitin ligase, ITCH. Here, we confirm this interaction and show ITCH binds directly to the carboxy-terminal half of pX from both human and bat hepatoviruses independently of ALIX. A small chemical compound (compound 5) designed to disrupt interactions between WW domains of NEDD4 ligases and substrate molecules blocked ITCH binding to pX and demonstrated substantial antiviral activity against HAV. CRISPR deletion or small interfering RNA (siRNA) knockdown of ITCH expression inhibited the release of a self-assembling nanocage protein fused to pX and also impaired the release of eHAV from infected cells. The release could be rescued by overexpression of wild-type ITCH, but not a catalytically inactive ITCH mutant. Despite this, we found no evidence that ITCH ubiquitylates pX or that eHAV release is strongly dependent upon Lys residues in pX. These data indicate ITCH plays an important role in the ESCRT-dependent release of quasi-enveloped hepatovirus, although the substrate molecule targeted for ubiquitylation remains to be determined. IMPORTANCE Mechanisms underlying the cellular release of quasi-enveloped hepatoviruses are only partially understood, yet play a crucial role in the pathogenesis of this common agent of viral hepatitis. Multiple NEDD4 family E3 ubiquitin ligases, including ITCH, have been reported to promote the budding of conventional enveloped viruses but are not known to function in the release of HAV or other picornaviruses from infected cells. Here, we show that the unique C-terminal pX extension of the VP1 capsid protein of HAV interacts directly with ITCH and that ITCH promotes eHAV release in a manner analogous to its role in budding of some conventional enveloped viruses. The catalytic activity of ITCH is required for efficient eHAV release and may potentially function to ubiquitylate the viral capsid or activate ESCRT components.


Assuntos
Vírus da Hepatite A , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Hepatovirus/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Vírus da Hepatite A/fisiologia , Ubiquitina-Proteína Ligases Nedd4/metabolismo
6.
PLoS Pathog ; 17(9): e1009960, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34591933

RESUMO

HAV-infected Ifnar1-/- mice recapitulate many of the cardinal features of hepatitis A in humans, including serum alanine aminotransferase (ALT) elevation, hepatocellular apoptosis, and liver inflammation. Previous studies implicate MAVS-IRF3 signaling in pathogenesis, but leave unresolved the role of IRF3-mediated transcription versus the non-transcriptional, pro-apoptotic activity of ubiquitylated IRF3. Here, we compare the intrahepatic transcriptomes of infected versus naïve Mavs-/- and Ifnar1-/- mice using high-throughput sequencing, and identify IRF3-mediated transcriptional responses associated with hepatocyte apoptosis and liver inflammation. Infection was transcriptionally silent in Mavs-/- mice, in which HAV replicates robustly within the liver without inducing inflammation or hepatocellular apoptosis. By contrast, infection resulted in the upregulation of hundreds of genes in Ifnar1-/- mice that develop acute hepatitis closely modeling human disease. Upregulated genes included pattern recognition receptors, interferons, chemokines, cytokines and other interferon-stimulated genes. Compared with Ifnar1-/- mice, HAV-induced inflammation was markedly attenuated and there were few apoptotic hepatocytes in livers of infected Irf3S1/S1Ifnar1-/- mice in which IRF3 is transcriptionally-inactive due to alanine substitutions at Ser-388 and Ser-390. Although transcriptome profiling revealed remarkably similar sets of genes induced in Irf3S1/S1Ifnar1-/- and Ifnar1-/- mice, a subset of genes was differentially expressed in relation to the severity of the liver injury. Prominent among these were both type 1 and type III interferons and interferon-responsive genes associated previously with apoptosis, including multiple members of the ISG12 and 2'-5' oligoadenylate synthetase families. Ifnl3 and Ifnl2 transcript abundance correlated strongly with disease severity, but mice with dual type 1 and type III interferon receptor deficiency remained fully susceptible to liver injury. Collectively, our data show that IRF3-mediated transcription is required for HAV-induced liver injury in mice and identify key IRF3-responsive genes associated with pathogenicity, providing a clear distinction from the transcription-independent role of IRF3 in liver injury following binge exposure to alcohol.


Assuntos
Hepatite A/metabolismo , Hepatite A/patologia , Fator Regulador 3 de Interferon/metabolismo , Fígado/patologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Transcriptoma
7.
Purinergic Signal ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906424

RESUMO

Bladder cancer (BC) is the most common cancer of the urinary tract. Bozepinib (BZP), a purine-derived molecule, is a potential compound for the treatment of cancer. Purinergic signaling consists of the activity of nucleosides and nucleotides present in the extracellular environment, modulating a variety of biological actions. In cancer, this signaling is mainly controlled by the enzymatic cascade involving the NTPDase/E-NPP family and ecto-5'-nucleotidase/CD73, which hydrolyze extracellular adenosine triphosphate (ATP) to adenosine (ADO). The aim of this work is to evaluate the activity of BZP in the purinergic system in BC cell lines and to compare its in vitro antitumor activity with cisplatin, a chemotherapeutic drug widely used in the treatment of BC. In this study, two different BC cell lines, grade 1 RT4 and the more aggressive grade 3 T24, were used along with a human fibroblast cell line MRC-5, a cell used to predict the selectivity index (SI). BZP shows strong antitumor activity, with notable IC50 values (8.7 ± 0.9 µM for RT4; 6.7 ± 0.7 µM for T24), far from the SI for cisplatin (SI for BZP: 19.7 and 25.7 for RT4 and T24, respectively; SI for cisplatin: 1.7 for T24). BZP arrests T24 cells in the G2/M phase of the cell cycle, inducing early apoptosis. Moreover, BZP increases ATP and ADP hydrolysis and gene/protein expression of the NPP1 enzyme in the T24 cell line. In conclusion, BZP shows superior activity compared to cisplatin against BC cell lines in vitro.

8.
Acta Paediatr ; 112(10): 2104-2112, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37332100

RESUMO

AIM: We examined the correlation between how long it took the parents of very low birthweight infants, born weighing up to 1500 g, to provide different kinds of autonomous care in a neonatal intensive care unit (NICU). METHODS: This prospective observational was conducted in the NICU of a Spanish hospital from 10 January 2020 to 3 May 2022. The unit had 11 beds single-family rooms and provided eight beds in an open bay room. The study examined breastfeeding, patient safety, participation in rounds, pain prevention and cleanliness. RESULTS: We studied 96 patients and their parents and there was no correlation between any type of care and the time it took parents to provide it autonomously. Parents in the single-family room cohort spent a median of 9.5 h per day between them in the NICU, while the parents in the open bay room spent 7.0 h with their infants (p = 0.03). However, parents in the single-family room group were able to recognise pain faster (p = 0.02). CONCLUSION: Parents in single-family rooms spent more time in the NICU and recognised pain faster but did not achieve autonomous care faster than parents in the open bay group.


Assuntos
Unidades de Terapia Intensiva Neonatal , Pais , Recém-Nascido , Feminino , Humanos , Lactente , Peso ao Nascer , Aleitamento Materno , Recém-Nascido de muito Baixo Peso
9.
Ann Diagn Pathol ; 61: 152030, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36055007

RESUMO

BACKGROUND: Urothelial carcinoma of the urinary bladder is the most common malignancy of the urinary system. Patients with low grade papillary urothelial carcinoma (LGPUC) usually have a low risk for tumor recurrence and progression; yet a subset of patients develop recurrence or grade/stage progression to high-grade papillary urothelial carcinoma (HGPUC). The clinicopathological and molecular factors that contribute to this progression are yet to be determined. OBJECTIVES: In our study, we aimed to assess the incidence and clinicopathological factors associated with tumor recurrence/progression of LGPUC. METHODS: Using a pathological database of surgical specimens from patients who underwent bladder biopsies and/or transurethral resection of bladder tumors (TURBTs) between August 01, 2011, and July 31, 2021, at a large academic medical center, a single-center retrospective cohort analysis was performed, and medical charts of patients were reviewed. RESULTS: Of the total 258 patients included, 157 (60.9 %) had "no recurrence", 85 (32.9 %) had ≥1 "recurrence of LGPUC", and 16 (6.2 %) had "grade progression to HGPUC". The mean follow-up time was 31.5 ± 32 months. Patients with "grade progression" and "recurrence of LGPUC" had larger mean tumor size on initial biopsy and multiple lesions on initial cystoscopy compared to those with "no recurrence." Interestingly, former smokers had 2.5- and 8.5-times higher risk of recurrence of LGPUC and grade progression, respectively. CONCLUSION: Since the majority of our patients did not develop recurrence, we question whether there is tendency to overclassify the papillomas as LGPUC based on the 2004 WHO/ISUP consensus grading classification.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Estudos Retrospectivos , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Hiperplasia/patologia
10.
J Clin Apher ; 36(5): 697-710, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34185332

RESUMO

We conducted a multicenter interventional study to assess the efficacy of Therakos ECP to treat steroid-resistant graft-vs-host disease (SRes-GVHD) after allogeneic HSCT and to identify biomarkers of GVHD response. A total of 62 patients were treated for acute SRes-GVHD (n = 37) or chronic SRes-GVHD (n = 25). Median time to best response was 35 days (range, 28-85) and 90 days (range, 27-240) in acute and chronic SRes-GVHD, respectively. Overall, 27 patients (72.9%) with SRes-aGVHD responded to treatment (40.5% CR and 32.4% PR). The response rate was significantly higher in grade I-II than in grade III-IV aGVHD (100% vs 50.0%, respectively, P-value = .001). In chronic SRes-GVHD, 22 patients (88%) achieved a clinical response (24.0% CR and 64% PR). Response was higher in moderate than in severe SRes-cGVHD (100% vs 75%, P = .096). In both acute and chronic SRes-GVHD patients, the percentage of peripheral blood CD3+ CD4+ was higher and CD3+ CD8+ lower in responding than nonresponding patients. Acute SRes-GVHD responding patients presented a higher number of Treg cells (CD4+ CD25+ CD127low/- ) at day 0 (P = .028) than nonresponding patients, differences that were maintained over the observation period. Phenotypic analysis of T-cell maturation showed a trend toward reduction in TCD8 naive cells, along with an increased percentage of TCD8 Mem Efect T cells after starting ECP in responding patients. None of the studied serum cytokines displayed statistically significant changes in either acute or chronic SRes-GVHD. ECP is an effective treatment for patients with SRes-GVHD. Biomarkers could help guide decision-making on ECP treatment initiation and duration.


Assuntos
Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Fotoferese/métodos , Adulto , Idoso , Biomarcadores , Citocinas/sangue , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Esteroides/uso terapêutico , Linfócitos T Reguladores/imunologia , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
11.
J Enzyme Inhib Med Chem ; 36(1): 1553-1563, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34251942

RESUMO

A series of 11 new substituted 1,5-dihydro-4,1-benzoxazepine derivatives was synthesised to study the influence of the methyl group in the 1-(benzenesulphonyl) moiety, the replacement of the purine by the benzotriazole bioisosteric analogue, and the introduction of a bulky substituent at position 6 of the purine, on the biological effects. Their inhibition against isolated HER2 was studied and the structure-activity relationships have been confirmed by molecular modelling studies. The most potent compound against isolated HER2 is 9a with an IC50 of 7.31 µM. We have investigated the effects of the target compounds on cell proliferation. The most active compound (7c) against all the tumour cell lines studied (IC50 0.42-0.86 µM) does not produce any modification in the expression of pro-caspase 3, but increases the caspase 1 expression, and promotes pyroptosis.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Receptor ErbB-2/metabolismo , Relação Estrutura-Atividade
12.
J Biol Chem ; 294(35): 13073-13092, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31308175

RESUMO

Reactivation of Kaposi's sarcoma-associated herpesvirus (KSHV) from latency requires the viral transactivator Rta to contact the host protein Jκ recombination signal-binding protein (RBP-Jκ or CSL). RBP-Jκ normally binds DNA sequence-specifically to determine the transcriptional targets of the Notch-signaling pathway, yet Notch alone cannot reactivate KSHV. We previously showed that Rta stimulates RBP-Jκ DNA binding to the viral genome. On a model viral promoter, this function requires Rta to bind to multiple copies of an Rta DNA motif (called "CANT" or Rta-c) proximal to an RBP-Jκ motif. Here, high-resolution ChIP/deep sequencing from infected primary effusion lymphoma cells revealed that RBP-Jκ binds nearly exclusively to different sets of viral genome sites during latency and reactivation. RBP-Jκ bound DNA frequently, but not exclusively, proximal to Rta bound to single, but not multiple, Rta-c motifs. To discover additional regulators of RBP-Jκ DNA binding, we used bioinformatics to identify cellular DNA-binding protein motifs adjacent to either latent or reactivation-specific RBP-Jκ-binding sites. Many of these cellular factors, including POU class homeobox (POU) proteins, have known Notch or herpesvirus phenotypes. Among a set of Rta- and RBP-Jκ-bound promoters, Rta transactivated only those that also contained POU motifs in conserved positions. On some promoters, POU factors appeared to inhibit RBP-Jκ DNA binding unless Rta bound to a proximal Rta-c motif. Moreover, POU2F1/Oct-1 expression was induced during KSHV reactivation, and POU2F1 knockdown diminished infectious virus production. Our results suggest that Rta and POU proteins broadly regulate DNA binding of RBP-Jκ during KSHV reactivation.


Assuntos
DNA/metabolismo , Herpesvirus Humano 8/metabolismo , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Fatores do Domínio POU/metabolismo , Transativadores/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Herpesvirus Humano 8/genética , Humanos
13.
Proc Natl Acad Sci U S A ; 114(25): 6587-6592, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28490497

RESUMO

The Picornaviridae are a diverse family of RNA viruses including many pathogens of medical and veterinary importance. Classically considered "nonenveloped," recent studies show that some picornaviruses, notably hepatitis A virus (HAV; genus Hepatovirus) and some members of the Enterovirus genus, are released from cells nonlytically in membranous vesicles. To better understand the biogenesis of quasi-enveloped HAV (eHAV) virions, we conducted a quantitative proteomics analysis of eHAV purified from cell-culture supernatant fluids by isopycnic ultracentrifugation. Amino acid-coded mass tagging (AACT) with stable isotopes followed by tandem mass spectrometry sequencing and AACT quantitation of peptides provided unambiguous identification of proteins associated with eHAV versus unrelated extracellular vesicles with similar buoyant density. Multiple peptides were identified from HAV capsid proteins (53.7% coverage), but none from nonstructural proteins, indicating capsids are packaged as cargo into eHAV vesicles via a highly specific sorting process. Other eHAV-associated proteins (n = 105) were significantly enriched for components of the endolysosomal system (>60%, P < 0.001) and included many common exosome-associated proteins such as the tetraspanin CD9 and dipeptidyl peptidase 4 (DPP4) along with multiple endosomal sorting complex required for transport III (ESCRT-III)-associated proteins. Immunoprecipitation confirmed that DPP4 is displayed on the surface of eHAV produced in cell culture or present in sera from humans with acute hepatitis A. No LC3-related peptides were identified by mass spectrometry. RNAi depletion studies confirmed that ESCRT-III proteins, particularly CHMP2A, function in eHAV biogenesis. In addition to identifying surface markers of eHAV vesicles, the results support an exosome-like mechanism of eHAV egress involving endosomal budding of HAV capsids into multivesicular bodies.


Assuntos
Proteínas do Capsídeo/metabolismo , Vírus da Hepatite A/metabolismo , Aminoácidos/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Dipeptidil Peptidase 4/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos/metabolismo , Exossomos/metabolismo , Humanos , Corpos Multivesiculares/metabolismo , Proteômica/métodos , Tetraspaninas/metabolismo , Vírion/metabolismo , Liberação de Vírus/fisiologia
14.
J Virol ; 92(23)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30232181

RESUMO

The quasi-envelopment of hepatitis A virus (HAV) capsids in exosome-like virions (eHAV) is an important but incompletely understood aspect of the hepatovirus life cycle. This process is driven by recruitment of newly assembled capsids to endosomal vesicles into which they bud to form multivesicular bodies with intraluminal vesicles that are later released at the plasma membrane as eHAV. The endosomal sorting complexes required for transport (ESCRT) are key to this process, as is the ESCRT-III-associated protein, ALIX, which also contributes to membrane budding of conventional enveloped viruses. YPX1or3L late domains in the structural proteins of these viruses mediate interactions with ALIX, and two such domains exist in the HAV VP2 capsid protein. Mutational studies of these domains are confounded by the fact that the Tyr residues (important for interactions of YPX1or3L peptides with ALIX) are required for efficient capsid assembly. However, single Leu-to-Ala substitutions within either VP2 YPX3L motif (L1-A and L2-A mutants) were well tolerated, albeit associated with significantly reduced eHAV release. In contrast, simultaneous substitutions in both motifs (L1,2-A) eliminated virus release but did not inhibit assembly of infectious intracellular particles. Immunoprecipitation experiments suggested that the loss of eHAV release was associated with a loss of ALIX recruitment. Collectively, these data indicate that HAV YPX3L motifs function as redundant late domains during quasi-envelopment and viral release. Since these motifs present little solvent-accessible area in the crystal structure of the naked extracellular capsid, the capsid structure may be substantially different during quasi-envelopment.IMPORTANCE Nonlytic release of hepatitis A virus (HAV) as exosome-like quasi-enveloped virions is a unique but incompletely understood aspect of the hepatovirus life cycle. Several lines of evidence indicate that the host protein ALIX is essential for this process. Tandem YPX3L "late domains" in the VP2 capsid protein could be sites of interaction with ALIX, but they are not accessible on the surface of an X-ray model of the extracellular capsid, raising doubts about this putative late domain function. Here, we describe YPX3L domain mutants that assemble capsids normally but fail to bind ALIX and be secreted as quasi-enveloped eHAV. Our data support late domain function for the VP2 YPX3L motifs and raise questions about the structure of the HAV capsid prior to and following quasi-envelopment.


Assuntos
Motivos de Aminoácidos , Proteínas do Capsídeo/metabolismo , Capsídeo/fisiologia , Carcinoma Hepatocelular/metabolismo , Vírus da Hepatite A/fisiologia , Vírion/fisiologia , Replicação Viral , Substituição de Aminoácidos , Capsídeo/química , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos , Hepatite A/genética , Hepatite A/metabolismo , Hepatite A/virologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Corpos Multivesiculares , Mutação , Conformação Proteica , Células Tumorais Cultivadas , Liberação de Vírus
16.
BMC Cardiovasc Disord ; 19(1): 203, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438858

RESUMO

BACKGROUND: Cellular therapies have been increasingly applied to diverse human diseases. Intracoronary infusion of bone marrow-derived mononuclear cells (BMMNC) has demonstrated to improve ventricular function after acute myocardial infarction. However, less information is available about the role of BMMNC therapy for the treatment of dilated myocardiopathies (DCs) of non-ischemic origin. This article presents the methodological description of a study aimed at investigating the efficacy of intracoronary injection of autologous BMMNCs in the improvement of the ventricular function of patients with DC. METHODS: This randomised, placebo-controlled, double-blinded phase IIb clinical trial compares the improvement on ventricular function (measured by the changes on the ejection fraction) of patients receiving the conventional treatment for DC in combination with a single dose of an intracoronary infusion of BMMNCs, with the functional recovery of patients receiving placebo plus conventional treatment. Patients assigned to both treatment groups are monitored for 24 months. This clinical trial is powered enough to detect a change in Left Ventricular Ejection Fraction (LVEF) equal to or greater than 9%, although an interim analysis is planned to re-calculate sample size. DISCUSSION: The study protocol was approved by the Andalusian Coordinating Ethics Committee for Biomedical Research (Comité Coordinador de Ética en Investigación Biomédica de Andalucia), the Spanish Medicines and Medical Devices Agency (Agencia Española de Medicamentos y Productos Sanitarios), and is registered at the EU Clinical Trials Register (EudraCT: 2013-002015-98). The publication of the trial results in scientific journals will be performed in accordance with the applicable regulations and guidelines to clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02033278 (First Posted January 10, 2014): https://clinicaltrials.gov/ct2/show/NCT02033278 ; EudraCT number: 2013-002015-98, EU CT Register: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-002015-98 . Trial results will also be published according to the CONSORT statement at conferences and reported peer-reviewed journals.


Assuntos
Transplante de Medula Óssea , Cardiomiopatia Dilatada/cirurgia , Função Ventricular Esquerda , Adolescente , Adulto , Idoso , Transplante de Medula Óssea/efeitos adversos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Espanha , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
17.
Eur J Haematol ; 100(5): 436-443, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29384595

RESUMO

OBJECTIVE: MLL gene is involved in more than 80 known genetic fusions in acute leukemia. To study the relevance of MLL partner gene and selected gene's expression, in this work, we have studied a cohort of 20 MLL-rearranged acute myeloid leukemia (AML). METHODS: Twenty MLL-rearranged AML patients along with a control cohort of 138 AML patients are included in this work. By RT-PCR and sequencing, MLL genetic fusion was characterized, and relative gene expression quantification was carried out for EVI1, MEIS1, MLL-3', RUNX1, SETBP1, HOXA5, and FLT3 genes. Risk stratification and association of MLL genetic partner and gene expression to overall survival, in the context of received therapy, were performed. RESULTS: MLLr cohort showed to have an OS more similar to intermediate-risk AML. Type of MLL genetic partner showed to be relevant in allo-HSCT response; having MLLT1 and MLLT3, a better benefit from it. Expression of MLL-3' region, EVI1 and FLT3, showed association with OS in patients undergoing allo-HSCT. CONCLUSION: We show that the MLL genetic partner could have implications in allo-HSCT response, and we propose three genes whose expression could be useful for the prognosis of this leukemia in patients undergoing allo-HSCT: 3' region of MLL, EVI1, and FLT3.


Assuntos
Regiões 3' não Traduzidas , Biomarcadores Tumorais , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , RNA Mensageiro , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Regulação Neoplásica da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Humanos , Hibridização in Situ Fluorescente , Lactente , Estimativa de Kaplan-Meier , Cariótipo , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Proteína do Locus do Complexo MDS1 e EVI1/genética , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Prognóstico , Modelos de Riscos Proporcionais , Translocação Genética , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genética
18.
Liver Int ; 37(7): 1013-1022, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27988985

RESUMO

BACKGROUND & AIMS: Cognitive dysfunction in cirrhotic patients with minimal hepatic encephalopathy (MHE) is associated with falls. Alterations in postural control and stability could contribute to increase falls risk in these patients. We aimed to assess whether postural control and direction-specific limits of stability are altered in cirrhotic patients with MHE compared to patients without MHE and controls. We also assessed if alterations in postural control correlate with neurological impairment and/or blood biomarkers. METHODS: Posturography analysis, attention Stroop test and bimanual and visuo-motor coordination tests were performed in 18 controls, 19 patients with cirrhosis without MHE and 17 with MHE, diagnosed by PHES. Posturography was assessed by NedSVE® /IBV system under four sensory conditions. Limits of stability and rhythmic weight-shifting tests were also performed. Blood ammonia and serum interleukins were also measured. Falls were assessed after 12-24 months follow-up. RESULTS: MHE patients show impaired balance, mainly on unstable surface with eyes open, with longer reaction and confinement times and lower success in Limits of Stability test compared to patients without MHE. Performance in attention and motor coordination tests correlated with most posturography parameters alterations. Logistic regression analysis shows that posturography parameters and bimanual coordination test are good predictors of falls. CONCLUSION: Balance patterns and limits of stability in MHE patients are impaired compared to patients without MHE and controls. This seems to contribute to a higher falls risk. Attention and motor coordination deficits could contribute to balance impairment in patients with MHE.


Assuntos
Acidentes por Quedas , Transtornos Cognitivos/etiologia , Cognição , Encefalopatia Hepática/etiologia , Cirrose Hepática/complicações , Equilíbrio Postural , Transtornos de Sensação/etiologia , Amônia/sangue , Atenção , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Feminino , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/fisiopatologia , Encefalopatia Hepática/psicologia , Humanos , Interleucinas/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/fisiopatologia , Cirrose Hepática/psicologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Exame Físico , Valor Preditivo dos Testes , Psicometria , Desempenho Psicomotor , Fatores de Risco , Transtornos de Sensação/diagnóstico , Transtornos de Sensação/fisiopatologia , Transtornos de Sensação/psicologia , Teste de Stroop
19.
Contact Dermatitis ; 77(1): 25-34, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28300294

RESUMO

BACKGROUND: Many skin diseases are associated with either increases or decreases in lamellar body secretion, or dysfunctional lamellar bodies. Consequently, diseased skin is characterized by reduced barrier function and altered lipid composition and organization. Human skin is commonly evaluated in vivo with non-invasive biophysical techniques. The dynamic functions of the skin are evaluated with repeat measurements such as the sorption-desorption test (SDT). OBJECTIVES: The aim of this study was to evaluate in vivo skin hydration-dehydration kinetics after treatment with a lipid system that mimics the morphology, structure and composition of lamellar bodies in both healthy and irritated human skin. METHODS: A patch with an aqueous solution of 2% sodium lauryl sulfate (SLS) was used to irritate the skin of the volunteers. The SDT was performed with the CM 820 corneometer. RESULTS: After treatment with this system, both healthy and SLS-irritated skin increased their ability to retain water and to release water slowly during the desorption phase. CONCLUSIONS: Treatment with this system seems to reinforce the barrier function in both healthy and SLS-irritated human skin. Therefore, the present study provides evidence that this system could be of interest for developing future treatments for protecting and repairing the skin.


Assuntos
Dermatite Irritante/diagnóstico , Absorção Cutânea , Testes Cutâneos/métodos , Água/metabolismo , Adulto , Epiderme/metabolismo , Feminino , Humanos , Irritantes/administração & dosagem , Metabolismo dos Lipídeos , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Pele
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