Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 141
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 187(5): 1255-1277.e27, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38359819

RESUMO

Despite the successes of immunotherapy in cancer treatment over recent decades, less than <10%-20% cancer cases have demonstrated durable responses from immune checkpoint blockade. To enhance the efficacy of immunotherapies, combination therapies suppressing multiple immune evasion mechanisms are increasingly contemplated. To better understand immune cell surveillance and diverse immune evasion responses in tumor tissues, we comprehensively characterized the immune landscape of more than 1,000 tumors across ten different cancers using CPTAC pan-cancer proteogenomic data. We identified seven distinct immune subtypes based on integrative learning of cell type compositions and pathway activities. We then thoroughly categorized unique genomic, epigenetic, transcriptomic, and proteomic changes associated with each subtype. Further leveraging the deep phosphoproteomic data, we studied kinase activities in different immune subtypes, which revealed potential subtype-specific therapeutic targets. Insights from this work will facilitate the development of future immunotherapy strategies and enhance precision targeting with existing agents.


Assuntos
Neoplasias , Proteogenômica , Humanos , Terapia Combinada , Genômica , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Proteômica , Evasão Tumoral
2.
Cell ; 186(16): 3476-3498.e35, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37541199

RESUMO

To improve the understanding of chemo-refractory high-grade serous ovarian cancers (HGSOCs), we characterized the proteogenomic landscape of 242 (refractory and sensitive) HGSOCs, representing one discovery and two validation cohorts across two biospecimen types (formalin-fixed paraffin-embedded and frozen). We identified a 64-protein signature that predicts with high specificity a subset of HGSOCs refractory to initial platinum-based therapy and is validated in two independent patient cohorts. We detected significant association between lack of Ch17 loss of heterozygosity (LOH) and chemo-refractoriness. Based on pathway protein expression, we identified 5 clusters of HGSOC, which validated across two independent patient cohorts and patient-derived xenograft (PDX) models. These clusters may represent different mechanisms of refractoriness and implicate putative therapeutic vulnerabilities.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Proteogenômica , Feminino , Humanos , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética
3.
Cell ; 184(19): 5031-5052.e26, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34534465

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with poor patient survival. Toward understanding the underlying molecular alterations that drive PDAC oncogenesis, we conducted comprehensive proteogenomic analysis of 140 pancreatic cancers, 67 normal adjacent tissues, and 9 normal pancreatic ductal tissues. Proteomic, phosphoproteomic, and glycoproteomic analyses were used to characterize proteins and their modifications. In addition, whole-genome sequencing, whole-exome sequencing, methylation, RNA sequencing (RNA-seq), and microRNA sequencing (miRNA-seq) were performed on the same tissues to facilitate an integrated proteogenomic analysis and determine the impact of genomic alterations on protein expression, signaling pathways, and post-translational modifications. To ensure robust downstream analyses, tumor neoplastic cellularity was assessed via multiple orthogonal strategies using molecular features and verified via pathological estimation of tumor cellularity based on histological review. This integrated proteogenomic characterization of PDAC will serve as a valuable resource for the community, paving the way for early detection and identification of novel therapeutic targets.


Assuntos
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Proteogenômica , Adenocarcinoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Ductal Pancreático/diagnóstico , Estudos de Coortes , Células Endoteliais/metabolismo , Epigênese Genética , Feminino , Dosagem de Genes , Genoma Humano , Glicólise , Glicoproteínas/biossíntese , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Neoplasias Pancreáticas/diagnóstico , Fenótipo , Fosfoproteínas/metabolismo , Fosforilação , Prognóstico , Proteínas Quinases/metabolismo , Proteoma/metabolismo , Especificidade por Substrato , Transcriptoma/genética
5.
Nat Mater ; 23(6): 741-746, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38740956

RESUMO

Confining materials to two-dimensional forms changes the behaviour of the electrons and enables the creation of new devices. However, most materials are challenging to produce as uniform, thin crystals. Here we present a synthesis approach where thin crystals are grown in a nanoscale mould defined by atomically flat van der Waals (vdW) materials. By heating and compressing bismuth in a vdW mould made of hexagonal boron nitride, we grow ultraflat bismuth crystals less than 10 nm thick. Due to quantum confinement, the bismuth bulk states are gapped, isolating intrinsic Rashba surface states for transport studies. The vdW-moulded bismuth shows exceptional electronic transport, enabling the observation of Shubnikov-de Haas quantum oscillations originating from the (111) surface state Landau levels. By measuring the gate-dependent magnetoresistance, we observe multi-carrier quantum oscillations and Landau level splitting, with features originating from both the top and bottom surfaces. Our vdW mould growth technique establishes a platform for electronic studies and control of bismuth's Rashba surface states and topological boundary modes1-3. Beyond bismuth, the vdW-moulding approach provides a low-cost way to synthesize ultrathin crystals and directly integrate them into a vdW heterostructure.

6.
J Virol ; 96(13): e0056622, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35703545

RESUMO

The family of human papillomaviruses (HPV) includes over 400 genotypes. Genus α genotypes generally infect the anogenital mucosa, and a subset of these HPV are a necessary, but not sufficient, cause of cervical cancer. Of the 13 high-risk (HR) and 11 intermediate-risk (IR) HPV associated with cervical cancer, genotypes 16 and 18 cause 50% and 20% of cases, respectively, whereas HPV16 dominates in other anogenital and oropharyngeal cancers. A plethora of ßHPVs are associated with cutaneous squamous cell carcinoma (CSCC), especially in sun-exposed skin sites of epidermodysplasia verruciformis (EV), AIDS, and immunosuppressed patients. Licensed L1 virus-like particle (VLP) vaccines, such as Gardasil 9, target a subset of αHPV but no ßHPV. To comprehensively target both α- and ßHPVs, we developed a two-component VLP vaccine, RG2-VLP, in which L2 protective epitopes derived from a conserved αHPV epitope (amino acids 17 to 36 of HPV16 L2) and a consensus ßHPV sequence in the same region are displayed within the DE loop of HPV16 and HPV18 L1 VLP, respectively. Unlike vaccination with Gardasil 9, vaccination of wild-type and EV model mice (Tmc6Δ/Δ or Tmc8Δ/Δ) with RG2-VLP induced robust L2-specific antibody titers and protected against ß-type HPV5. RG2-VLP protected rabbits against 17 αHPV, including those not covered by Gardasil 9. HPV16- and HPV18-specific neutralizing antibody responses were similar between RG2-VLP- and Gardasil 9-vaccinated animals. However, only transfer of RG2-VLP antiserum effectively protected naive mice from challenge with all ßHPVs tested. Taken together, these observations suggest RG2-VLP's potential as a broad-spectrum vaccine to prevent αHPV-driven anogenital, oropharyngeal, and ßHPV-associated cutaneous cancers. IMPORTANCE Licensed preventive HPV vaccines are composed of VLPs derived by expression of major capsid protein L1. They confer protection generally restricted to infection by the αHPVs targeted by the up-to-9-valent vaccine, and their associated anogenital cancers and genital warts, but do not target ßHPV that are associated with CSCC in EV and immunocompromised patients. We describe the development of a two-antigen vaccine protective in animal models against known oncogenic αHPVs as well as diverse ßHPVs by incorporation into HPV16 and HPV18 L1 VLP of 20-amino-acid conserved protective epitopes derived from minor capsid protein L2.


Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Papillomaviridae , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Vacinas de Partículas Semelhantes a Vírus , Alphapapillomavirus/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Carcinoma de Células Escamosas/prevenção & controle , Epitopos/imunologia , Feminino , Papillomavirus Humano 16/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Papillomaviridae/imunologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Coelhos , Vacinas de Partículas Semelhantes a Vírus/imunologia
7.
Nat Chem Biol ; 16(7): 731-739, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32393898

RESUMO

Glucose is catabolized by two fundamental pathways, glycolysis to make ATP and the oxidative pentose phosphate pathway to make reduced nicotinamide adenine dinucleotide phosphate (NADPH). The first step of the oxidative pentose phosphate pathway is catalyzed by the enzyme glucose-6-phosphate dehydrogenase (G6PD). Here we develop metabolite reporter and deuterium tracer assays to monitor cellular G6PD activity. Using these, we show that the most widely cited G6PD antagonist, dehydroepiandosterone, does not robustly inhibit G6PD in cells. We then identify a small molecule (G6PDi-1) that more effectively inhibits G6PD. Across a range of cultured cells, G6PDi-1 depletes NADPH most strongly in lymphocytes. In T cells but not macrophages, G6PDi-1 markedly decreases inflammatory cytokine production. In neutrophils, it suppresses respiratory burst. Thus, we provide a cell-active small molecule tool for oxidative pentose phosphate pathway inhibition, and use it to identify G6PD as a pharmacological target for modulating immune response.


Assuntos
Inibidores Enzimáticos/farmacologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Animais , Linhagem Celular , Desidroepiandrosterona/farmacologia , Relação Dose-Resposta a Droga , Ensaios Enzimáticos , Glucose/metabolismo , Glucosefosfato Desidrogenase/imunologia , Glucosefosfato Desidrogenase/metabolismo , Glicólise/imunologia , Células HCT116 , Células Hep G2 , Humanos , Imunidade Inata , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/citologia , Linfócitos/enzimologia , Linfócitos/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/enzimologia , Macrófagos/imunologia , NADP/antagonistas & inibidores , NADP/metabolismo , Neutrófilos/citologia , Neutrófilos/enzimologia , Neutrófilos/imunologia , Via de Pentose Fosfato/imunologia
8.
J Neurooncol ; 159(2): 389-395, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35751740

RESUMO

BACKGROUND: The current standard of care for patients with a large brain metastasis and limited intracranial disease burden is surgical resection and post-operative single fraction stereotactic radiosurgery (SRS). However, post-operative SRS can still lead to substantial rates of local failure (LF), radiation necrosis (RN), and meningeal disease (MD). Pre-operative SRS may reduce the risk of RN and MD, while fractionated treatments may improve local control by allowing delivery of higher biological effective dose. We hypothesize that pre-operative fractionated stereotactic radiation therapy (FSRT) can minimize rates of LF, RN, and MD. METHODS: A retrospective, multi-institutional analysis was conducted and included patients who had pre-operative FSRT for a large or symptomatic brain metastasis. Pertinent demographic, clinical, radiation, surgical, and follow up data were collected for each patient. A primary measurement was the rate of a composite endpoint of (1) LF, (2) MD, and/or (3) Grade 2 or higher (symptomatic) RN. RESULTS: 53 patients with 55 lesions were eligible for analysis. FSRT was prescribed to a dose of 24-25 Gy in 3-5 fractions. There were 0 LFs, 3 Grade 2-3 RN events, and 1 MD occurrence, which corresponded to an 8% per-patient composite endpoint event rate. CONCLUSIONS: In this study, the composite endpoint of 8% for pre-operative FSRT was improved compared to previously reported rates with post-operative SRS of 49-60% (N107C, Mahajan etal. JCOG0504) and pre-operative SRS endpoints of 20.6% (PROPS-BM). Pre-operative FSRT appears to be safe, effective, and may decrease the incidence of adverse outcomes. Prospective validation is needed.


Assuntos
Neoplasias Encefálicas , Lesões por Radiação , Radiocirurgia , Humanos , Estudos Retrospectivos
9.
Angiogenesis ; 24(2): 363-377, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33201372

RESUMO

NADPH oxidase 4 (Nox4) is a major isoform of NADPH oxidases playing an important role in many biological processes. Previously we have shown that Nox4 is highly expressed in retinal blood vessels and is upregulated in oxygen-induced retinopathy (OIR). However, the exact role of endothelial Nox4 in retinal angiogenesis remains elusive. Herein, using endothelial cell (EC)-specific Nox4 knockout (Nox4EC-KO) mice, we investigated the impact of endothelial Nox4 deletion on retinal vascular development and pathological angiogenesis during OIR. Our results show that deletion of Nox4 in ECs led to retarded retinal vasculature development with fewer, blunted-end tip cells and sparser, dysmorphic filopodia at vascular front, and reduced density of vascular network in superficial, deep, and intermediate layers in postnatal day 7 (P7), P12, and P17 retinas, respectively. In OIR, loss of endothelial Nox4 had no effect on hyperoxia-induced retinal vaso-obliteration at P9 but significantly reduced aberrant retinal neovascularization at P17 and decreased the deep layer capillary density at P25. Ex vivo study confirmed that lack of Nox4 in ECs impaired vascular sprouting. Mechanistically, loss of Nox4 significantly reduced expression of VEGF, p-VEGFR2, integrin αV, angiopoietin-2, and p-ERK1/2, attenuating EC migration and proliferation. Taken together, our results indicate that endothelial Nox4 is important for retinal vascular development and contributes to pathological angiogenesis, likely through regulation of VEGF/VEGFR2 and angiopoietin-2/integrin αV/ERK pathways. In addition, our study suggests that endothelial Nox4 appears to be essential for intraretinal revascularization after hypoxia. These findings call for caution on targeting endothelial Nox4 in ischemic/hypoxic retinal diseases.


Assuntos
Células Endoteliais/enzimologia , Endotélio Vascular/enzimologia , Deleção de Genes , NADPH Oxidase 4/metabolismo , Neovascularização Fisiológica , Neovascularização Retiniana/enzimologia , Vasos Retinianos/crescimento & desenvolvimento , Animais , Camundongos , Camundongos Knockout , NADPH Oxidase 4/genética , Neovascularização Retiniana/genética
10.
Neurosurg Focus ; 50(2): E2, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33524943

RESUMO

OBJECTIVE: High-grade gliomas (HGGs) inevitably recur and progress despite resection and standard chemotherapies and radiation. Viral therapies have emerged as a theoretically favorable adjuvant modality that might overcome intrinsic factors of HGGs that confer treatment resistance. METHODS: The authors present the results of systematic searches of the MEDLINE and ClinicalTrials.gov databases that were performed for clinical trials published or registered up to July 15, 2020. RESULTS: Fifty-one completed clinical trials were identified that made use of a virus-based therapeutic strategy to treat HGG. The two main types of viral therapies were oncolytic viruses and viral vectors for gene therapy. Among clinical trials that met inclusion criteria, 20 related to oncolytic viruses and 31 to gene therapy trials. No oncolytic viruses have progressed to phase III clinical trial testing, although there have been many promising early-phase results and no reported cases of encephalitis or death due to viral therapy. Three phase III trials in which viral gene therapy was used have been completed but have not resulted in any FDA-approved therapy. Recent efforts in this area have been focused on the delivery of suicide genes such as herpes simplex virus thymidine kinase and cytosine deaminase. CONCLUSIONS: Decades of research efforts and an improving understanding of the immunomodulatory effects of viral therapies for gliomas are informing ongoing clinical efforts aimed at improving outcomes in patients with HGG. The available clinical data reveal varied efficacy among different virus-based treatment strategies.


Assuntos
Glioblastoma , Glioma , Terapia Viral Oncolítica , Vírus Oncolíticos , Adulto , Glioblastoma/terapia , Glioma/terapia , Humanos , Recidiva Local de Neoplasia
11.
J Med Internet Res ; 23(7): e29514, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34081611

RESUMO

BACKGROUND: The COVID-19 pandemic began in early 2021 and placed significant strains on health care systems worldwide. There remains a compelling need to analyze factors that are predictive for patients at elevated risk of morbidity and mortality. OBJECTIVE: The goal of this retrospective study of patients who tested positive with COVID-19 and were treated at NYU (New York University) Langone Health was to identify clinical markers predictive of disease severity in order to assist in clinical decision triage and to provide additional biological insights into disease progression. METHODS: The clinical activity of 3740 patients at NYU Langone Hospital was obtained between January and August 2020; patient data were deidentified. Models were trained on clinical data during different parts of their hospital stay to predict three clinical outcomes: deceased, ventilated, or admitted to the intensive care unit (ICU). RESULTS: The XGBoost (eXtreme Gradient Boosting) model that was trained on clinical data from the final 24 hours excelled at predicting mortality (area under the curve [AUC]=0.92; specificity=86%; and sensitivity=85%). Respiration rate was the most important feature, followed by SpO2 (peripheral oxygen saturation) and being aged 75 years and over. Performance of this model to predict the deceased outcome extended 5 days prior, with AUC=0.81, specificity=70%, and sensitivity=75%. When only using clinical data from the first 24 hours, AUCs of 0.79, 0.80, and 0.77 were obtained for deceased, ventilated, or ICU-admitted outcomes, respectively. Although respiration rate and SpO2 levels offered the highest feature importance, other canonical markers, including diabetic history, age, and temperature, offered minimal gain. When lab values were incorporated, prediction of mortality benefited the most from blood urea nitrogen and lactate dehydrogenase (LDH). Features that were predictive of morbidity included LDH, calcium, glucose, and C-reactive protein. CONCLUSIONS: Together, this work summarizes efforts to systematically examine the importance of a wide range of features across different endpoint outcomes and at different hospitalization time points.


Assuntos
Algoritmos , COVID-19/diagnóstico , COVID-19/mortalidade , Hospitalização , Adolescente , Adulto , Idoso , Área Sob a Curva , Criança , Pré-Escolar , Diabetes Mellitus , Feminino , Hospitais , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Morbidade , Cidade de Nova Iorque/epidemiologia , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Triagem , Adulto Jovem
12.
J Allergy Clin Immunol ; 144(1): 171-182, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30578874

RESUMO

BACKGROUND: Fibrosis and stricture are major comorbidities in patients with eosinophilic esophagitis (EoE). Lysyl oxidase (LOX), a collagen cross-linking enzyme, has not been investigated in the context of EoE. OBJECTIVE: We investigated regulation of epithelial LOX expression as a novel biomarker and functional effector of fibrostenotic disease conditions associated with EoE. METHODS: LOX expression was analyzed by using RNA-sequencing, PCR assays, and immunostaining in patients with EoE; cytokine-stimulated esophageal 3-dimensional organoids; and fibroblast-epithelial cell coculture, the latter coupled with fluorescence-activated cell sorting. RESULTS: Gene ontology and pathway analyses linked TNF-α and LOX expression in patients with EoE, which was validated in independent sets of patients with fibrostenotic conditions. TNF-α-mediated epithelial LOX upregulation was recapitulated in 3-dimensional organoids and coculture experiments. We find that fibroblast-derived TNF-α stimulates epithelial LOX expression through activation of nuclear factor κB and TGF-ß-mediated signaling. In patients receiver operating characteristic analyses suggested that LOX upregulation indicates disease complications and fibrostenotic conditions in patients with EoE. CONCLUSIONS: There is a novel positive feedback mechanism in epithelial LOX induction through fibroblast-derived TNF-α secretion. Esophageal epithelial LOX might have a role in the development of fibrosis with substantial translational implications.


Assuntos
Biomarcadores/metabolismo , Esofagite Eosinofílica/genética , Células Epiteliais/fisiologia , Esôfago/patologia , Fibroblastos/fisiologia , Proteína-Lisina 6-Oxidase/genética , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Células Cultivadas , Criança , Pré-Escolar , Técnicas de Cocultura , Constrição Patológica , Esofagite Eosinofílica/diagnóstico , Feminino , Fibrose , Ontologia Genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteína-Lisina 6-Oxidase/metabolismo , Regulação para Cima , Adulto Jovem
13.
Diabetologia ; 62(3): 531-543, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30612139

RESUMO

AIMS/HYPOTHESIS: Müller glia (MG) are major sources of retinal cytokines, and their activation is closely linked to retinal inflammation and vascular leakage in diabetic retinopathy. Previously, we demonstrated that X-box binding protein 1 (XBP1), a transcription factor activated by endoplasmic reticulum (ER) stress in diabetic retinopathy, is involved in regulation of inflammation in retinal endothelial cells. Now, we have explored the role of XBP1 and ER stress in the regulation of MG-derived proinflammatory factors, and their influence on vascular permeability in diabetic retinopathy. METHODS: MG-specific conditional Xbp1 knockout (Xbp1Müller-/-) mice were generated by crossing Xbp1 flox/flox mice with Müller-Cre transgenic mice. Diabetes was modelled by induction with streptozotocin, and retinal vascular permeability was measured with FITC-conjugated dextran 2 months after induction. Primary Müller cells were isolated from Xbp1Müller-/- and Xbp1Müller+/+ mice and exposed to hypoxia and high levels of glucose. Levels of ER-stress and inflammatory factors were examined by real-time PCR, western blotting or immunohistochemistry. RESULTS: Xbp1Müller-/- mice exhibited normal retinal development and retinal function and expressed similar levels of ER-stress and inflammatory genes to Xbp1Müller+/+ littermates. In diabetes-inducing conditions, compared with Xbp1Müller+/+ mice, Xbp1Müller-/- mice had higher mRNA levels of retinal Vegf (also known as Vegfa) and Tnf-α (also known as Tnf) and ER-stress marker genes Grp78 (also known as Hspa5), Atf4, Chop (also known as Ddit3) and Atf6 and higher protein levels of vascular endothelial growth factor (VEGF), TNF-α, phospho-c-Jun N-terminal kinase (JNK), 78 kDa glucose-regulated protein (GRP78), phospho-eukaryotic translation initiation factor (eIF)2α and activating transcription factor (ATF)6. Retinal vascular permeability was significantly higher in diabetic Xbp1Müller-/- mice than in diabetic Xbp1Müller+/+ mice (p < 0.01). Results obtained in vitro with primary Müller cells isolated from Xbp1Müller-/- mice confirmed higher expression levels of inflammatory and ER-stress markers (but not GRP78) than in cells from Xbp1Müller+/+ mice. Moreover, XBP1-deficient Müller cells were more susceptible to high-glucose- or hypoxia-induced ER stress and inflammation than cells from Xbp1Müller+/+ mice. Inhibition of ER stress with chemical chaperones suppressed hypoxia-induced VEGF and TNF-α production in XBP1-deficient Müller cells. CONCLUSIONS/INTERPRETATION: Our results have revealed an important role of XBP1 and ER stress in MG-driven retinal inflammation, and suggest that targeting ER stress may represent a promising approach for the prevention and treatment of diabetic retinopathy.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Células Ependimogliais/metabolismo , Inflamação/metabolismo , Retina/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo , Animais , Permeabilidade Capilar/fisiologia , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/patologia , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/fisiologia , Células Ependimogliais/patologia , Inflamação/patologia , Camundongos , Retina/patologia
14.
J Virol ; 92(15)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29743371

RESUMO

To address how L2-specific antibodies prevent human papillomavirus (HPV) infection of the genital tract, we generated neutralizing monoclonal antibodies (MAbs) WW1, a rat IgG2a that binds L2 residues 17 to 36 (like mouse MAb RG1), and JWW3, a mouse IgG2b derivative of Mab24 specific for L2 residues 58 to 64. By Western blotting, WW1 recognized L2 of 29/34 HPV genotypes tested, compared to only 13/34 for RG1 and 25/34 for JWW3. WW1 IgG and F(ab')2 bound HPV16 pseudovirions similarly; however, whole IgG provided better protection against HPV vaginal challenge. Passive transfer of WW1 IgG was similarly protective in wild-type and neonatal Fc receptor (FcRn)-deficient mice, suggesting that protection by WW1 IgG is not mediated by FcRn-dependent transcytosis. Rather, local epithelial disruption, required for genital infection and induced by either brushing or nonoxynol-9 treatment, released serum IgG in the genital tract, suggesting Fc-independent exudation. Depletion of neutrophils and macrophages reduced protection of mice upon passive transfer of whole WW1 or JWW3 IgGs. Similarly, IgG-mediated protection by L2 MAbs WW1, JWW3, and RG1 was reduced in Fc receptor knockout compared to wild-type mice. However, levels of in vitro neutralization by WW1 IgG were similar in TRIM21 knockout and wild-type cells, indicating that Fc does not contribute to antibody-dependent intracellular neutralization (ADIN). In conclusion, the Fc domain of L2-specific IgGs is not active for ADIN, but it opsonizes bound extracellular pseudovirions for phagocytes in protecting mice from intravaginal HPV challenge. Systemically administered neutralizing IgG can access the site of infection in an abrasion via exudation without the need for FcRn-mediated transcytosis.IMPORTANCE At least 15 alpha HPV types are causative agents for 5% of all cancers worldwide, and beta types have been implicated in nonmelanoma skin cancer, whereas others produce benign papillomas, such as genital warts, associated with considerable morbidity and health systems costs. Vaccines targeting the minor capsid protein L2 have the potential to provide broad-spectrum immunity against medically relevant HPVs of divergent genera via the induction of broadly cross-neutralizing serum IgG. Here we examine the mechanisms by which L2-specific serum IgG reaches the viral inoculum in the genital tract to effect protection. Abrasion of the vaginal epithelium allows the virus to access and infect basal keratinocytes, and our findings suggest that this also permits the local exudation of neutralizing IgG and vaccine-induced sterilizing immunity. We also demonstrate the importance of Fc-mediated phagocytosis of L2 antibody-virion complexes for humoral immunity, a protective mechanism that is not detected by current in vitro neutralization assays.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Fragmentos Fc das Imunoglobulinas , Imunoglobulina G , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Animais , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/farmacologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/farmacologia , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/imunologia , Domínios Proteicos , Ratos , Receptores Fc/genética , Receptores Fc/imunologia
15.
Allergy ; 74(12): 2449-2460, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31267532

RESUMO

BACKGROUND: Germline-encoded innate immune pattern recognition receptors (PRR) are expressed at epithelial surfaces and modulate epithelial defenses. Evidence suggests that stimulation of the Toll-like receptor (TLR) family of PRR may regulate epithelial barrier integrity by upregulating tight junction (TJ) complex protein expression, but it is not known whether this mechanism is utilized in esophageal epithelial cells. TJ complex proteins maintain intact barrier function and are dysregulated in atopic disorders including eosinophilic esophagitis. METHODS: Pattern recognition receptors expression was assessed in EoE and control primary esophageal epithelial cells, demonstrating robust expression of TLR2 and TLR3. The three-dimensional air-liquid interface culture (ALI) model was used to test whether TLR2 or TLR3 stimulation alters epithelial barrier function using an in vitro model of human epithelium. Transepithelial electrical resistance (TEER) and FITC-Dextran permeability were evaluated to assess membrane permeability. ALI cultures were evaluated by histology, immunohistochemistry, Western blotting, and chromatin immunoprecipitation (ChIP). RESULTS: TLR3 stimulation did not change TEER in the ALI model. TLR2 stimulation increased TEER (1.28- to 1.31-fold) and decreased paracellular permeability to FITC-Dextran, and this effect was abolished by treatment with anti-TLR2 blocking antibody. TJ complex proteins claudin-1 and zonula occludens-1 were upregulated following TLR2 stimulation, and ChIP assay demonstrated altered histone 4 acetyl binding at the TJP1 enhancer and CLDN1 enhancer and promoter following zymosan treatment, implying the occurrence of durable chromatin changes. CONCLUSIONS: Our findings implicate the TLR2 pathway as a potential regulator of esophageal epithelial barrier function and suggest that downstream chromatin modifications are associated with this effect.


Assuntos
Mucosa Esofágica/metabolismo , Receptor 2 Toll-Like/agonistas , Células Cultivadas , Células Epiteliais/metabolismo , Mucosa Esofágica/patologia , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Receptores de Reconhecimento de Padrão/metabolismo , Junções Íntimas , Receptores Toll-Like/metabolismo
16.
Neurosurg Rev ; 42(2): 209-226, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29027018

RESUMO

Hemangioblastomas (HBs) are benign, highly vascular tumors, often characterized by loss of function of the von Hippel-Lindau (vHL) gene. They are the most common central nervous system tumor observed in vHL syndrome. Loss of function of the vHL gene creates a "pseudo-hypoxic" state, causing overactivation of hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF)-related pathways. In some cases, HBs can rapidly increase in size during pregnancy to then present acutely, which most frequently occurs after the 20th gestational week. These changes in size usually occur from enlargement of the cystic component of the HB. Due to their preferred location in the posterior fossa near critical structures as well as along the spinal cord, such cases can present with severe neurological deficits, requiring urgent surgical intervention in a multidisciplinary setting. However, the reasons for this acute flare-up during pregnancy remain poorly understood, as are the reasons why this occurs in only a subset of tumors. Unveiling the etiology for this clinical scenario can affect the treatment of HBs, as it will contribute to the understanding of the pathophysiology of such a transformation from a quiescent lesion to a symptomatic one, not only in the setting of pregnancy. Identifying the correct triggers and the conditions initiating and mediating this switch will enable us to develop preventive medications which should allow us to keep the tumor in its quiescent phase. In this pathophysiological review, we investigate the association between HB growth and pregnancy based on an analysis > 40 such published cases. We suggest that the proangiogenic state of pregnancy is the leading etiology for this striking association, and to support the argument, we discuss its potential impact on HIF overexpression in a non-hypoxic manner through activation of the PI3K/Akt/mTOR pathway by proangiogenic factors. Specifically, we discuss the involvement of placental growth factor (PlGF) and its receptor vascular endothelial growth factor receptor 1 (VEGFR-1) in various pathologic processes that can lead to the formation and growth of peritumoral edema and cysts, which are the primary causes for the development of any symptoms in HB. Both PlGF and VEGFR-1 are expressed at increased levels during pregnancy, and both have been reported as part of various pathological processes, including angiogenesis and tumorigenesis. The unique feature that both do essentially not show any significant negative impact on regular physiological processes makes them attractive therapeutic targets since very little side effects are expected. Further research into the effects of anti-PlGF or anti-VEGFR-1 therapy in HB is therefore recommended.


Assuntos
Neoplasias Cerebelares/sangue , Neoplasias Cerebelares/patologia , Hemangioblastoma/sangue , Hemangioblastoma/patologia , Complicações Neoplásicas na Gravidez/sangue , Complicações Neoplásicas na Gravidez/patologia , Neoplasias Cerebelares/etiologia , Feminino , Hemangioblastoma/etiologia , Humanos , Hipóxia , Fator de Crescimento Placentário/sangue , Gravidez , Complicações Neoplásicas na Gravidez/etiologia , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
17.
Artigo em Inglês | MEDLINE | ID: mdl-29914949

RESUMO

Over the past decade, the prevalence of infections involving methicillin-resistant Staphylococcus aureus (MRSA) in patients with cystic fibrosis (CF) has increased significantly. Tedizolid (TZD) demonstrates excellent activity against MRSA and a favorable safety profile. The pharmacokinetics of several antibiotics have been shown to be altered in CF patients. The purpose of this study was to characterize the pharmacokinetics of tedizolid in this population. Eleven patients with CF were randomized to receive tedizolid phosphate at 200 mg orally or intravenously once daily for 3 doses with a minimum 2-day washout, followed by crossover to the remaining dosage form. Plasma and expectorated sputum were collected following the third dose of each dosage form for analysis. Population pharmacokinetic analysis was performed using the maximum likelihood expectation maximization method, and the disposition of TZD was described by a two-compartment model. The sputum concentrations exceeded the unbound plasma concentrations with an estimated mean sputum-to-unbound plasma penetration ratio of 2.88 (coefficient of variation, 50.3%). The estimated population mean ± standard deviation of total clearance, central volume of distribution, and bioavailability were 9.72 ± 1.62 liters/h, 61.6 ± 6.94 liters, and 1.04 ± 0.232, respectively. The total clearance was higher in CF patients than in healthy volunteers; however, it was similar to published data for patients with complicated skin and skin structure infections (cSSSIs). This study demonstrates that the oral bioavailability of tedizolid is excellent in patients with CF and that the plasma pharmacokinetics are similar to those reported for patients with cSSSIs.


Assuntos
Antibacterianos/sangue , Antibacterianos/farmacocinética , Fibrose Cística/sangue , Fibrose Cística/microbiologia , Organofosfatos/sangue , Organofosfatos/farmacocinética , Oxazóis/sangue , Oxazóis/farmacocinética , Plasma/metabolismo , Administração Intravenosa/métodos , Administração Oral , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Estudos Prospectivos , Escarro/metabolismo
18.
Genome Res ; 25(3): 413-25, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25504520

RESUMO

Candida albicans is a commensal fungus of the human gastrointestinal tract and a prevalent opportunistic pathogen. To examine diversity within this species, extensive genomic and phenotypic analyses were performed on 21 clinical C. albicans isolates. Genomic variation was evident in the form of polymorphisms, copy number variations, chromosomal inversions, subtelomeric hypervariation, loss of heterozygosity (LOH), and whole or partial chromosome aneuploidies. All 21 strains were diploid, although karyotypic changes were present in eight of the 21 isolates, with multiple strains being trisomic for Chromosome 4 or Chromosome 7. Aneuploid strains exhibited a general fitness defect relative to euploid strains when grown under replete conditions. All strains were also heterozygous, yet multiple, distinct LOH tracts were present in each isolate. Higher overall levels of genome heterozygosity correlated with faster growth rates, consistent with increased overall fitness. Genes with the highest rates of amino acid substitutions included many cell wall proteins, implicating fast evolving changes in cell adhesion and host interactions. One clinical isolate, P94015, presented several striking properties including a novel cellular phenotype, an inability to filament, drug resistance, and decreased virulence. Several of these properties were shown to be due to a homozygous nonsense mutation in the EFG1 gene. Furthermore, loss of EFG1 function resulted in increased fitness of P94015 in a commensal model of infection. Our analysis therefore reveals intra-species genetic and phenotypic differences in C. albicans and delineates a natural mutation that alters the balance between commensalism and pathogenicity.


Assuntos
Candida albicans/genética , Variação Genética , Fenótipo , Aneuploidia , Candida albicans/classificação , Candidíase/microbiologia , Cromossomos Fúngicos , Variações do Número de Cópias de DNA , Evolução Molecular , Genoma Fúngico , Genótipo , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Seleção Genética , Análise de Sequência de DNA
19.
J Virol ; 91(15)2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28515303

RESUMO

Mus musculus papillomavirus 1 (MmuPV1/MusPV1) induces persistent papillomas in immunodeficient mice but not in common laboratory strains. To facilitate the study of immune control, we sought an outbred and immunocompetent laboratory mouse strain in which persistent papillomas could be established. We found that challenge of SKH1 mice (Crl:SKH1-Hrhr) with MmuPV1 by scarification on their tail resulted in three clinical outcomes: (i) persistent (>2-month) papillomas (∼20%); (ii) transient papillomas that spontaneously regress, typically within 2 months (∼15%); and (iii) no visible papillomas and viral clearance (∼65%). SKH1 mice with persistent papillomas were treated by using a candidate preventive/therapeutic naked-DNA vaccine that expresses human calreticulin (hCRT) fused in frame to MmuPV1 E6 (mE6) and mE7 early proteins and residues 11 to 200 of the late protein L2 (hCRTmE6/mE7/mL2). Three intramuscular DNA vaccinations were delivered biweekly via in vivo electroporation, and both humoral and CD8 T cell responses were mapped and measured. Previously persistent papillomas disappeared within 2 months after the final vaccination. Coincident virologic clearance was confirmed by in situ hybridization and a failure of disease to recur after CD3 T cell depletion. Vaccination induced strong mE6 and mE7 CD8+ T cell responses in all mice, although they were significantly weaker in mice that initially presented with persistent warts than in those that spontaneously cleared their infection. A human papillomavirus 16 (HPV16)-targeted version of the DNA vaccine also induced L2 antibodies and protected mice from vaginal challenge with an HPV16 pseudovirus. Thus, MmuPV1 challenge of SKH1 mice is a promising model of spontaneous and immunotherapy-directed clearances of HPV-related disease.IMPORTANCE High-risk-type human papillomaviruses (hrHPVs) cause 5% of all cancer cases worldwide, notably cervical, anogenital, and oropharyngeal cancers. Since preventative HPV vaccines have not been widely used in many countries and do not impact existing infections, there is considerable interest in the development of therapeutic vaccines to address existing disease and infections. The strict tropism of HPV requires the use of animal papillomavirus models for therapeutic vaccine development. However, MmuPV1 failed to grow in common laboratory strains of mice with an intact immune system. We show that MmuPV1 challenge of the outbred immunocompetent SKH1 strain produces both transient and persistent papillomas and that vaccination of the mice with a DNA expressing an MmuPV1 E6E7L2 fusion with calreticulin can rapidly clear persistent papillomas. Furthermore, an HPV16-targeted version of the DNA can protect against vaginal challenge with HPV16, suggesting the promise of this approach to both prevent and treat papillomavirus-related disease.


Assuntos
Modelos Animais de Doenças , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/terapia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/imunologia , Animais , Anticorpos Antivirais/sangue , Linfócitos T CD8-Positivos/imunologia , Injeções Intramusculares , Camundongos , Resultado do Tratamento , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
20.
Adv Exp Med Biol ; 1074: 421-427, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721972

RESUMO

The molecular chaperone endoplasmic reticulum protein 29 (ERp29) plays a critical role in protein folding, trafficking, and secretion. Though ubiquitously expressed, ERp29 is upregulated in response to ER stress and is found at higher levels in certain cell types such as secretory epithelial cells and neurons. As an ER resident protein, ERp29 shares many structural and functional similarities with protein disulfide isomerases, but is not regarded as part of this family due to several key differences. The broad expression and myriad roles of ERp29 coupled with its upregulation via the unfolded protein response (UPR) upon ER stress have implicated ERp29 in a range of cellular processes and diseases. We summarize the diverse activities of ERp29 in protein trafficking, cell survival and apoptosis, and ER homeostasis and highlight a potential role of ERp29 in neuroprotection in retinal and neurodegenerative diseases.


Assuntos
Proteínas de Choque Térmico/fisiologia , Doenças Neurodegenerativas/metabolismo , Degeneração Retiniana/metabolismo , Apoptose , Reparo do DNA , Estresse do Retículo Endoplasmático , Células Epiteliais/metabolismo , Proteínas do Olho/fisiologia , Junções Comunicantes/fisiologia , Homeostase , Humanos , Terapia de Alvo Molecular , Doenças Neurodegenerativas/prevenção & controle , Doenças Neurodegenerativas/terapia , Neurônios/metabolismo , Dobramento de Proteína , Transporte Proteico , Degeneração Retiniana/prevenção & controle , Degeneração Retiniana/terapia , Resposta a Proteínas não Dobradas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA