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1.
Heliyon ; 10(6): e27636, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38509988

RESUMO

Rationale and objectives: Coronary computed tomography angiography (CCTA) is becoming increasingly important for the diagnostic workup of coronary artery disease, nevertheless, imaging of in-stent stenosis remains challenging. For the first time, spectral imaging in Ultra High Resolution (UHR) is now possible in clinically available photon counting CT. The aim of this work is to determine the optimal virtual monoenergetic image (VMI) for imaging in-stent stenoses in cardiac stents. Materials and methods: 6 stents with inserted hypodense stenoses were scanned in an established phantom in UHR mode. Images were reconstructed with 3 different kernels for spectral data (Qr56, Qr64, Qr72) with varying levels of sharpness. Based on region of interest (ROI) measurements image quality parameters including contrast-to-noise ratio (CNR) were analyzed for all available VMI (40 keV-190 keV). Finally, based on quantitative results and VMI used in clinical routine, a set of VMI was included in a qualitative reading. Results: CNR showed significant variations across different keV levels (p < 0.001). Due to reduced noise there was a focal maximum in the VMI around 65 keV. The peak values were observed for kernel Qr56 at 116 keV with 19.47 ± 8.67, for kernel Qr64 at 114 keV with 13.56 ± 6.58, and for kernel Qr72 at 106 keV with 12.19 ± 3.25. However, in the qualitative evaluation the VMI with lower keV (55 keV) performed best. Conclusions: Based on these experimental results, a photon counting CCTA in UHR with stents should be reconstructed with the Qr72 kernel for the assessment of in-stent stenoses, and a VMI 55 keV should be computed for the evaluation.

3.
NPJ Microgravity ; 10(1): 14, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316814

RESUMO

The validity of venous ultrasound (V-US) for the diagnosis of deep vein thrombosis (DVT) during spaceflight is unknown and difficult to establish in diagnostic accuracy and diagnostic management studies in this context. We performed a systematic review of the use of V-US in the upper-body venous system in spaceflight to identify microgravity-related changes and the effect of venous interventions to reverse them, and to assess appropriateness of spaceflight V-US with terrestrial standards. An appropriateness tool was developed following expert panel discussions and review of terrestrial diagnostic studies, including criteria relevant to crew experience, in-flight equipment, assessment sites, ultrasound modalities, and DVT diagnosis. Microgravity-related findings reported as an increase in internal jugular vein (IJV) cross-sectional area and pressure were associated with reduced, stagnant, and retrograde flow. Changes were on average responsive to venous interventions using lower body negative pressure, Bracelets, Valsalva and Mueller manoeuvres, and contralateral IJV compression. In comparison with terrestrial standards, spaceflight V-US did not meet all appropriateness criteria. In DVT studies (n = 3), a single thrombosis was reported and only ultrasound modality criterion met the standards. In the other studies (n = 15), all the criteria were appropriate except crew experience criterion, which was appropriate in only four studies. Future practice and research should account for microgravity-related changes, evaluate individual effect of venous interventions, and adopt Earth-based V-US standards.

4.
Gut ; 73(7): 1110-1123, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38378253

RESUMO

OBJECTIVE: Intestinal fibrosis is considered an inevitable consequence of chronic IBD, leading to stricture formation and need for surgery. During the process of fibrogenesis, extracellular matrix (ECM) components critically regulate the function of mesenchymal cells. We characterised the composition and function of ECM in fibrostenosing Crohn's disease (CD) and control tissues. DESIGN: Decellularised full-thickness intestinal tissue platforms were tested using three different protocols, and ECM composition in different tissue phenotypes was explored by proteomics and validated by quantitative PCR (qPCR) and immunohistochemistry. Primary human intestinal myofibroblasts (HIMFs) treated with milk fat globule-epidermal growth factor 8 (MFGE8) were evaluated regarding the mechanism of their antifibrotic response, and the action of MFGE8 was tested in two experimental intestinal fibrosis models. RESULTS: We established and validated an optimal decellularisation protocol for intestinal IBD tissues. Matrisome analysis revealed elevated MFGE8 expression in CD strictured (CDs) tissue, which was confirmed at the mRNA and protein levels. Treatment with MFGE8 inhibited ECM production in normal control HIMF but not CDs HIMF. Next-generation sequencing uncovered functionally relevant integrin-mediated signalling pathways, and blockade of integrin αvß5 and focal adhesion kinase rendered HIMF non-responsive to MFGE8. MFGE8 prevented and reversed experimental intestinal fibrosis in vitro and in vivo. CONCLUSION: MFGE8 displays antifibrotic effects, and its administration may represent a future approach for prevention of IBD-induced intestinal strictures.


Assuntos
Antígenos de Superfície , Doença de Crohn , Matriz Extracelular , Fibrose , Proteínas do Leite , Humanos , Animais , Doença de Crohn/patologia , Doença de Crohn/metabolismo , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia , Antígenos de Superfície/metabolismo , Matriz Extracelular/metabolismo , Miofibroblastos/metabolismo , Modelos Animais de Doenças , Camundongos , Ratos
5.
Eur J Radiol ; 167: 111031, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37591133

RESUMO

PURPOSE: Purpose of this study is to re-evaluate the accuracy and diagnostic reliability of virtual non-contrast (VNC) images acquired with the photon-counting computed tomography (PCCT) after an update of the CT scanner software. METHODS: Fifty-four patients were retrospectively enrolled. VNC images were reconstructed from true non-contrast (TNC) images (VNCn) and contrast-enhanced images in portal venous contrast phase (VNCv). Additionally, a liver-specific VNC (VNCl) was assessed. Quantitative image properties of VNC and TNC images were compared and consistency between VNC images was evaluated. Regions of interest were drawn in the liver, spleen, renal cortex, aorta, muscle and subcutaneous fat. RESULTS: Attenuation values on all VNC images differed significantly from TNC images in the liver, renal cortex, aorta and fat. A mean offset of <10HU between TNC and all VNC images was found in the liver, spleen and muscle. The comparison of TNC and VNCl images revealed an offset < 10HU in fat. Differences ≤ 10HU between TNC and VNCv and between TNC and VNCl were found in 68%, respectively in 75%. Differences ≤ 15HU were found in 79%, respectively in 92% of all measurements. Differences ≤ 10HU between TNC and VNCn were found in 79% and differences ≤ 15HU in 85%. CONCLUSION: Although there are statistically significant differences between HU values measured on TNC and VNC images in certain tissues, the minor offsets measured in liver and spleen suggest a good clinical applicability of VNCv and VNCl images. The significantly lower offset in subcutaneous fat on VNCl images suggests a superiority for measurements in adipose tissues.


Assuntos
Fígado , Tomografia Computadorizada por Raios X , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Fígado/diagnóstico por imagem , Abdome
6.
Matrix Biol ; 113: 1-21, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36108990

RESUMO

OBJECTIVE: Inflammatory bowel diseases (IBD) cause chronic intestinal damage and extracellular matrix (ECM) remodeling. The ECM may play an active role in inflammation by modulating immune cell functions, including cell adhesion, but this hypothesis has not been tested in IBD. DESIGN: Primary human intestinal myofibroblast (HIMF)-derived ECM from IBD and controls, 3D decellularized colon or ECM molecule-coated scaffolds were tested for their adhesiveness for T cells. Matrisome was analysed via proteomics. Functional integrin blockade was used to investigate the underlying mechanism. Analysis of the pediatric Crohn's disease (CD) RISK inception cohort was used to explore an altered ECM gene expression as a potential predictor for a future complicated disease course. RESULTS: HIMF-derived ECM and 3D decellularized colonic ECM from IBD bound more T cells compared to control. Control HIMFs exposed to the pro-inflammatory cytokines Iinterleukin-1ß (IL-1ß) and tumor necrosis factor (TNF) increased, and to transforming growth factor-ß1 (TGF-ß1) decreased ECM adhesiveness to T cells. Matrisome analysis of the HIMF-derived ECM revealed collagen VI as a major culprit for differences in T cell adhesion. Collagen VI knockdown in HIMF reduced adhesion T cell as did the blockage of integrin αvß1. Elevated gene expression of collagen VI in biopsies of pediatric CD patients was linked to risk for future stricturing disease. CONCLUSION: HIMF-derived ECM in IBD binds a remarkably enhanced number of T cells, which is dependent on Collagen VI and integrin αvß1. Collagen VI expression is a risk factor for a future complicated CD course. Blocking immune cells retention may represent a novel approach to treatment in IBD.


Assuntos
Doenças Inflamatórias Intestinais , Miofibroblastos , Criança , Humanos , Miofibroblastos/metabolismo , Adesividade , Linfócitos T/patologia , Colágeno/metabolismo , Inflamação/metabolismo
7.
Gut ; 71(1): 55-67, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33468536

RESUMO

OBJECTIVE: Creeping fat, the wrapping of mesenteric fat around the bowel wall, is a typical feature of Crohn's disease, and is associated with stricture formation and bowel obstruction. How creeping fat forms is unknown, and we interrogated potential mechanisms using novel intestinal tissue and cell interaction systems. DESIGN: Tissues from normal, UC, non-strictured and strictured Crohn's disease intestinal specimens were obtained. The muscularis propria matrisome was determined via proteomics. Mesenteric fat explants, primary human preadipocytes and adipocytes were used in multiple ex vivo and in vitro cell migration systems on muscularis propria muscle cell derived or native extracellular matrix. Functional experiments included integrin characterisation via flow cytometry and their inhibition with specific blocking antibodies and chemicals. RESULTS: Crohn's disease muscularis propria cells produced an extracellular matrix scaffold which is in direct spatial and functional contact with the immediately overlaid creeping fat. The scaffold contained multiple proteins, but only fibronectin production was singularly upregulated by transforming growth factor-ß1. The muscle cell-derived matrix triggered migration of preadipocytes out of mesenteric fat, fibronectin being the dominant factor responsible for their migration. Blockade of α5ß1 on the preadipocyte surface inhibited their migration out of mesenteric fat and on 3D decellularised intestinal tissue extracellular matrix. CONCLUSION: Crohn's disease creeping fat appears to result from the migration of preadipocytes out of mesenteric fat and differentiation into adipocytes in response to an increased production of fibronectin by activated muscularis propria cells. These new mechanistic insights may lead to novel approaches for prevention of creeping fat-associated stricture formation.


Assuntos
Adipócitos/patologia , Movimento Celular , Doença de Crohn/patologia , Intestinos/patologia , Músculo Liso/patologia , Adipogenia/fisiologia , Tecido Adiposo/patologia , Diferenciação Celular , Células Cultivadas , Matriz Extracelular/patologia , Fibronectinas/metabolismo , Humanos , Alicerces Teciduais
8.
Aliment Pharmacol Ther ; 55(3): 277-291, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34932238

RESUMO

BACKGROUND: Ozanimod, a high selective sphingosine 1 phosphate (S1P) receptor (S1PR) 1/5 modulator was approved by the Food and Drug Administration for the treatment of adult patients with moderately to severely active ulcerative colitis. Additional S1PR modulators are being tested in clinical development programmes for both ulcerative colitis and Crohn's disease. AIM: To provide an overview of advances in understanding S1PRs biology and summarise preclinical and clinical investigations of S1P receptor modulators in chronic inflammatory disease with special emphasis on inflammatory bowel diseases (IBD). METHODS: We performed a narrative review using PubMed and ClinicalTrials.gov. RESULTS: Through S1PRs, S1P regulates multiple cellular processes, including proliferation, migration, survival, and vascular barrier integrity. The S1PRs function of regulating lymphocyte trafficking is well known, but new functions of S1PRs expand our knowledge of S1PRs biology. Several S1PR modulators are in clinical development for both ulcerative colitis and Crohn's disease and have shown promise in phase II and III studies with ozanimod now being approved for ulcerative colitis. CONCLUSIONS: S1P receptor modulators constitute a novel, promising, safe, and convenient strategy for the treatment of IBD.


Assuntos
Doenças Inflamatórias Intestinais , Moduladores do Receptor de Esfingosina 1 Fosfato , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Fosfatos/uso terapêutico , Esfingosina/uso terapêutico , Moduladores do Receptor de Esfingosina 1 Fosfato/uso terapêutico , Receptores de Esfingosina-1-Fosfato , Estados Unidos
9.
Environ Toxicol Chem ; 40(9): 2484-2498, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34288068

RESUMO

The potential for delayed mortality following short-term episodic pollution events was evaluated by exposing cladocerans (Ceriodaphnia dubia) and rainbow trout (Oncorhynchus mykiss) to zinc (Zn) in various 1- to 48-h and 1- to 96-h exposures, respectively, followed by transferring the exposed organisms to clean water for up to 47 h for C. dubia and up to 95 h for trout for additional observation. For C. dubia, 1-h exposures of up to 3790 µg Zn/L never resulted in mortality during the actual Zn exposures, but by 48 h, a 1-h exposure to 114 µg/L, a concentration similar to the present US national water quality acute criterion for the test water conditions, ultimately killed 70% of C. dubia. With C. dubia, the speed of action of Zn toxicity was faster for intermediate concentrations than for the highest concentrations tested. For rainbow trout, pronounced delayed mortalities by 96 h only occurred following ≥8-h exposures. For both species, ultimate mortalities from Zn exposures ≤8 h mostly presented as delayed mortalities, whereas for exposures ≥24 h, almost all ultimate mortalities presented during the actual exposure periods. With Zn, risks of delayed mortality following exposures to all concentrations tested were much greater for the more sensitive, small-bodied invertebrate (C. dubia) than for the less sensitive, larger-bodied fish (rainbow trout). These results, along with previous studies, show that delayed mortality is an important consideration in evaluating risks to aquatic organisms from brief, episodic exposures to some substances. Environ Toxicol Chem 2021;40:2484-2498. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.


Assuntos
Cladocera , Oncorhynchus mykiss , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água , Zinco/toxicidade
10.
Environ Toxicol Chem ; 40(9): 2425-2442, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34187091

RESUMO

Perfluorooctane sulfonate (PFOS) is one of the dominant perfluoroalkyl substances (PFAS) detected in aquatic ecosystems. It has been used in a wide range of industrial and consumer products for decades. The unique properties of PFOS, including its stability and resistance to degradation, have made it highly persistent in the aquatic environment. Because of its persistence, potential toxicity, and occurrence in aquatic ecosystems, interest in PFOS has increased in recent decades. Despite this interest, current information on the environmental distribution of PFOS in ambient surface waters of the United States is fairly limited. This critical review summarizes the currently available literature on PFOS occurrence in surface waters across the United States and highlights existing data gaps. Available data are largely from a handful of study areas with known PFAS manufacturing or industrial uses, with much of the data collected from freshwater systems in eastern states and the upper Midwest. Measured PFOS concentrations in surface waters vary widely, over 8 orders of magnitude, with the highest concentrations occurring downstream from manufacturing and industrial use plants, areas near aqueous film-forming foam-use sites, and sites where PFOS precursors were used in textile treatment. Non-point source-related occurrences are highest near urbanized areas with high population densities. Current data illustrate the occurrence of PFOS in surface waters across multiple US states. Additional data are needed to better understand PFOS occurrence in US aquatic ecosystems, particularly in estuarine and marine systems and where monitoring data are not available (e.g., southwestern, central, and western United States). Additional PFOS occurrence data would provide valuable information on potential spatial and temporal variability in surface waters and possible risks posed to aquatic ecosystems. Environ Toxicol Chem 2021;40:2425-2442. Published 2021. This article is a U.S. Government work and is in the public domain in the USA.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/toxicidade , Ecossistema , Monitoramento Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/toxicidade
11.
J Clin Invest ; 131(2)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33463541

RESUMO

IL-36 is a member of the IL-1 superfamily and consists of three agonists and one receptor antagonist (IL-36Ra). The three endogenous agonists, IL-36α, -ß, and -γ, act primarily as proinflammatory cytokines, and their signaling through the IL-36 receptor (IL-36R) promotes immune cell infiltration and secretion of inflammatory and chemotactic molecules. However, IL-36 signaling also fosters secretion of profibrotic soluble mediators, suggesting a role in fibrotic disorders. IL-36 isoforms and IL-36 have been implicated in inflammatory diseases including psoriasis, arthritis, inflammatory bowel diseases, and allergic rhinitis. Moreover, IL-36 has been connected to fibrotic disorders affecting the kidney, lung, and intestines. This review summarizes the expression, cellular source, and function of IL-36 in inflammation and fibrosis in various organs, and proposes that IL-36 modulation may prove valuable in preventing or treating inflammatory and fibrotic diseases and may reveal a mechanistic link between inflammation and fibrosis.


Assuntos
Regulação da Expressão Gênica , Interleucina-1/biossíntese , Animais , Fibrose , Humanos , Especificidade de Órgãos
12.
J Intensive Care Med ; 36(3): 277-283, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31774029

RESUMO

BACKGROUND: Indications for inferior vena cava filter (IVCF) placement are controversial. This study assesses the proportion of different indications for IVCF placement and the associated 30-day event rates and predictors for all-cause mortality, deep vein thrombosis (DVT), pulmonary embolism, and bleeding after IVCF placement. METHOD: In this 5-year retrospective cohort observational study in a quaternary care center, consecutive patients with IVCF placement were identified through cross-matching of 3 database sets and classified into 3 indication groups defined as "standard" in patients with venous thromboembolism (VTE) and contraindication to anticoagulants, "extended" in patients with VTE but no contraindication to anticoagulants, and "prophylactic" in patients without VTE. RESULTS: We identified 1248 IVCF placements, that is, 238 (19.1%) IVCF placements for standard indications, 583 (46.7%) IVCF placements for extended indications, and 427 (34.2%) IVCF placements for prophylactic indications. Deep vein thrombosis rates [95% confidence interval] were higher in the extended (8.06% [5.98-10.58]) and prophylactic (7.73% [5.38-10.68]) groups than in the standard group (3.36% [1.46-6.52]). Mortality rates were higher in the standard group (12.18% [8.31-17.03]) than in the extended group (7.55% [5.54-9.99]) and the prophylactic (5.85% [3.82-8.52]) group. Bleeding rates were higher in the standard group (4.62% [2.33-8.12]) than in the prophylactic group (2.11% [0.97-3.96]). Best predictors for VTE were acute medical conditions; best predictors for mortality were age, acute medical conditions, cancer, and Medicare health insurance. CONCLUSIONS: Prophylactic and extended indications account for the majority of IVCF placements. The standard indication is associated with the lowest VTE rate that may be explained by the competing risk of mortality higher in this group and related to the underlying medical conditions and bleeding risk. In the prophylactic group (no VTE at baseline), the exceedingly high DVT rate may be related to the IVCF placement.


Assuntos
Embolia Pulmonar , Filtros de Veia Cava , Tromboembolia Venosa , Idoso , Humanos , Medicare , Mortalidade , Prognóstico , Embolia Pulmonar/terapia , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos , Tromboembolia Venosa/terapia
13.
J Dig Dis ; 21(6): 308-314, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32410365

RESUMO

The rapidly increasing incidence of inflammatory bowel disease (IBD) in South America, eastern Europe, Asia, and Africa has resulted in a global public health challenge. Intestinal fibrosis is a common complication in patients with long-term IBD, which may develop into stenosis and subsequent obstruction. Hitherto, the origin of IBD is unclear and several factors may be involved, including genetic, immune, environmental and microbial influences. Little is known about how the recurrent inflammation in patients with IBD develops into intestinal fibrosis and currently, there is no suitable treatment to reverse intestinal fibrosis in these patients. Here, we review the role of immune components in the pathogenesis of IBD and intestinal fibrosis, including cytokine networks, host-microbiome interactions, and immune cell trafficking.


Assuntos
Citocinas/imunologia , Imunidade/imunologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Intestinos/patologia , Fibrose/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Intestinos/imunologia
14.
Environ Toxicol Chem ; 39(1): 101-117, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31880834

RESUMO

Regulatory jurisdictions worldwide are increasingly incorporating bioavailability-based toxicity models into development of protective values (PVALs) for freshwater and saltwater aquatic life (e.g., water quality criteria, standards, and/or guidelines) for metals. Use of such models for regulatory purposes should be contingent on their ability to meet performance criteria as specified through a model-validation process. Model validation generally involves an assessment of a model's appropriateness, relevance, and accuracy. We review existing guidance for validation of bioavailability-based toxicity models, recommend questions that should be addressed in model-validation studies, discuss model study type and design considerations, present several new ways to evaluate model performance in validation studies, and suggest a framework for use of model validation in PVAL development. We conclude that model validation should be rigorous but flexible enough to fit the user's purpose. Although a model can never be fully validated to a level of zero uncertainty, it can be sufficiently validated to fit a specific purpose. Therefore, support (or lack of support) for a model should be presented in such a way that users can choose their own level of acceptability. We recommend that models be validated using experimental designs and endpoints consistent with the data sets that were used to parameterize and calibrate the model and validated across a broad range of geographically and ecologically relevant water types. Environ Toxicol Chem 2019;39:101-117. © 2019 SETAC.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Monitoramento Ambiental/métodos , Água Doce/química , Metais , Modelos Biológicos , Poluentes Químicos da Água , Animais , Organismos Aquáticos/metabolismo , Disponibilidade Biológica , Monitoramento Ambiental/legislação & jurisprudência , Metais/metabolismo , Metais/toxicidade , Reprodutibilidade dos Testes , Especificidade da Espécie , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Qualidade da Água
15.
J Immunol ; 203(11): 2777-2790, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31636239

RESUMO

Options for effective prevention and treatment of epidemic allergic diseases remain limited, and particularly so for IgE-mediated food allergies. We previously found that mouse low-affinity anti-human IgE mAbs with KD in the 10-6-10-8 M range were capable of blocking allergic reactivity without triggering immediate allergic mediator release. In this study, we humanized three parent low affinity allergic response inhibitor (LARI) mouse anti-human IgE mAbs and characterized their biological and immunological features, refined the lead candidate for further clinical development, examined their safety profiles, determined their therapeutic efficiency, and explored the mechanism of action potentially responsible for their therapeutic effects. LARI profoundly blocked cat- and peanut-allergic IgE-mediated basophil activation, inhibited acute release of both prestored and newly synthesized mediator from human mast cells, suppressed peanut-specific IgE-mediated passive cutaneous anaphylaxis, and attenuated dansyl IgE-mediated systemic anaphylaxis in human FcεRIα transgenic mice. Safety testing demonstrated that concentrations of LARI well above therapeutic levels failed to trigger immediate release of prestored and newly synthesized allergic mediators, failed to promote robust cytokine/chemokine production from allergic effector cells, and did not elicit allergic reactivity in an animal model of cutaneous and systemic anaphylaxis. Mechanistic studies revealed that LARI downregulated surface FcεRI receptors and IgE via internalization of the IgE/FcεRI, promoted a partial mediator depletion pathway leading to slow release of small amount of mediators, and functioned as a partial antagonist to inhibit FcεRI signaling phosphorylation of Syk, Akt, Erk, and p38 MAPK. These studies demonstrate that targeting surface-bound IgE with LARI profoundly suppresses human allergic reactivity while displaying an excellent safety profile.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Receptores de IgE/imunologia , Humanos
16.
Front Immunol ; 10: 138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30833944

RESUMO

Mast cells (MC) are important immune sentinels found in most tissue and widely recognized for their role as mediators of Type I hypersensitivity. However, they also secrete anti-cancer mediators such as tumor necrosis factor alpha (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF). The purpose of this study was to investigate adipose tissue as a new source of MC in quantities that could be used to study MC biology focusing on their ability to bind to and kill breast cancer cells. We tested several cell culture media previously demonstrated to induce MC differentiation. We report here the generation of functional human MC from adipose tissue. The adipose-derived mast cells (ADMC) are phenotypically and functionally similar to connective tissue expressing tryptase, chymase, c-kit, and FcεRI and capable of degranulating after cross-linking of FcεRI. The ADMC, sensitized with anti-HER2/neu IgE antibodies with human constant regions (trastuzumab IgE and/or C6MH3-B1 IgE), bound to and released MC mediators when incubated with HER2/neu-positive human breast cancer cells (SK-BR-3 and BT-474). Importantly, the HER2/neu IgE-sensitized ADMC induced breast cancer cell (SK-BR-3) death through apoptosis. Breast cancer cell apoptosis was observed after the addition of cell-free supernatants containing mediators released from FcεRI-challenged ADMC. Apoptosis was significantly reduced when TNF-α blocking antibodies were added to the media. Adipose tissue represents a source MC that could be used for multiple research purposes and potentially as a cell-mediated cancer immunotherapy through the expansion of autologous (or allogeneic) MC that can be targeted to tumors through IgE antibodies recognizing tumor specific antigens.


Assuntos
Tecido Adiposo/citologia , Neoplasias da Mama , Mastócitos/imunologia , Apoptose , Células Cultivadas , Citotoxicidade Imunológica , Humanos
17.
Cell Death Dis ; 10(2): 59, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683851

RESUMO

Breast cancer (BC) cells (BCCs) can retain cellular quiescence for decades, a phenomenon referred to as dormancy. BCCs show preference for the bone marrow (BM) where they can remain dormant for decades. Targeting BCCs within the BM is a challenge since the dormant BCCs reside within BM stroma, also residence for hematopoietic stem cells (HSCs). Dormant BCCs could behave as cancer stem cells (CSCs). The CSCs and HSCs are similar by function and also, by commonly expressed genes. The method by which dormant BCCs transition into clinically metastatic cells remains unclear. This study tested the hypothesis that macrophages (MΦs) within BM stroma, facilitates dormancy or reverse this state into metastatic cells. MΦs exhibiting an M2 phenotype constitute ~10% of cultured BM stroma. The M2 MΦs form gap junctional intercellular communication (GJIC) with CSCs, resulting in cycling quiescence, reduced proliferation and carboplatin resistance. In contrast, MΦs expressing the M1 phenotype reversed BC dormancy. Activation of M2a MΦs via the toll-like receptor 4 (TLR4) switched to M1 phenotype. The switch can occur by direct activation of M2a MΦs, or indirectly through activation of mesenchymal stem cells. M1 MΦ-derived exosomes activated NFкB to reverse quiescent BCCs to cycling cells. Using an in vivo model of BC dormancy, injected Mi MOs sensitized BCCs to carboplatin and increased host survival. In summary, we have shown how BM stromal MΦs, through exosomes, regulate the behavior of BCCs, by either inducing or reversing dormancy.


Assuntos
Medula Óssea/patologia , Neoplasias da Mama/patologia , Comunicação Celular , Exossomos/metabolismo , Macrófagos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Adolescente , Adulto , Animais , Neoplasias da Mama/tratamento farmacológico , Carboplatina/uso terapêutico , Células Cultivadas , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos , Feminino , Junções Comunicantes , Xenoenxertos , Humanos , Macrófagos/classificação , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Receptor 4 Toll-Like/metabolismo , Adulto Jovem
18.
Artigo em Inglês | MEDLINE | ID: mdl-28861134

RESUMO

Undergraduate students learn about mammalian cell culture applications in introductory biology courses. However, laboratory modules are rarely designed to provide hands-on experience with mammalian cells or teach cell culture techniques, such as trypsinization and cell counting. Students are more likely to learn about cell culture using bacteria or yeast, as they are typically easier to grow, culture, and manipulate given the equipment, tools, and environment of most undergraduate biology laboratories. In contrast, the utilization of mammalian cells requires a dedicated biological safety cabinet and rigorous antiseptic techniques. For this reason, we have devised a laboratory module and method herein that familiarizes students with common cell culture procedures, without the use of a sterile hood or large cell culture facility. Students design and perform a time-efficient inquiry-based cell viability experiment using HeLa cells and tools that are readily available in an undergraduate biology laboratory. Students will become familiar with common techniques such as trypsinizing cells, cell counting with a hemocytometer, performing serial dilutions, and determining cell viability using trypan blue dye. Additionally, students will work with graphing software to analyze their data and think critically about the mechanism of death on a cellular level. Two different adaptations of this inquiry-based lab are presented-one for non-biology majors and one for biology majors. Overall, these laboratories aim to expose students to mammalian cell culture and basic techniques and help them to conceptualize their application in scientific research.

19.
Nanomedicine ; 13(6): 2037-2048, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28457935

RESUMO

The transformation of monocyte-derived macrophages into lipid-laden foam cells is one inflammatory process underlying atherosclerotic disease. Previous studies have demonstrated that fullerene derivatives (FDs) have inflammation-blunting properties. Thus, it was hypothesized that FD could inhibit the transformation process underlying foam cell formation. Fullerene derivatives inhibited the phorbol myristic acid/oxidized low-density lipoprotein-induced differentiation of macrophages into foam cells as determined by lipid staining and morphology.Lipoprotein-induced generation of TNF-α, C5a-induced MC activation, ICAM-1 driven adhesion, and CD36 expression were significantly inhibited in FD treated cells compared to non-treated cells. Inhibition appeared to be mediated through the NF-κB pathway as FD reduced expression of NF-κB and atherosclerosis-associated genes. Compared to controls, FD dramatically inhibited plaque formation in arteries of apolipoprotein E null mice. Thus, FD may be an unrecognized therapy to prevent atherosclerotic lesions via inhibition of foam cell formation and MC stabilization.


Assuntos
Células Espumosas/efeitos dos fármacos , Fulerenos/farmacologia , Mastócitos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Placa Aterosclerótica/prevenção & controle , Animais , Células Cultivadas , Células Espumosas/metabolismo , Células Espumosas/patologia , Humanos , Masculino , Mastócitos/metabolismo , Mastócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Células U937
20.
Clin Lipidol ; 6(3): 305-314, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22162978

RESUMO

Nonalcoholic fatty liver disease is now regarded as the most common form of chronic liver disease in adults and children. The close association between nonalcoholic fatty liver disease (NAFLD) and the metabolic syndrome has been extensively described. Moreover, a growing body of evidence suggest that NAFLD by itself confers a substantial cardiovascular risk independent of the other components of the metabolic syndrome. Given the significant potential for morbidity and mortality in these patients, and the large proportion of both pediatric and adult population affected, it is important that we clearly define the overall risk, identify early predictors for cardiovascular disease progression, and establish management strategies. In this article, we will focus on current data linking NAFLD and the severity of liver damage present in children with cardiovascular risk.

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