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1.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33941687

RESUMO

Here, we present a physiologically relevant model of the human pulmonary alveoli. This alveolar lung-on-a-chip platform is composed of a three-dimensional porous hydrogel made of gelatin methacryloyl with an inverse opal structure, bonded to a compartmentalized polydimethylsiloxane chip. The inverse opal hydrogel structure features well-defined, interconnected pores with high similarity to human alveolar sacs. By populating the sacs with primary human alveolar epithelial cells, functional epithelial monolayers are readily formed. Cyclic strain is integrated into the device to allow biomimetic breathing events of the alveolar lung, which, in addition, makes it possible to investigate pathological effects such as those incurred by cigarette smoking and severe acute respiratory syndrome coronavirus 2 pseudoviral infection. Our study demonstrates a unique method for reconstitution of the functional human pulmonary alveoli in vitro, which is anticipated to pave the way for investigating relevant physiological and pathological events in the human distal lung.


Assuntos
Dispositivos Lab-On-A-Chip , Modelos Biológicos , Alvéolos Pulmonares/fisiologia , Células Epiteliais Alveolares , Antivirais/farmacologia , Fumar Cigarros/efeitos adversos , Dimetilpolisiloxanos/química , Gelatina/química , Humanos , Hidrogéis/química , Metacrilatos/química , Porosidade , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/patologia , Respiração , Mucosa Respiratória/citologia , Mucosa Respiratória/fisiologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade
2.
Int J Mol Sci ; 24(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37958979

RESUMO

Bacterial contamination during space missions is problematic for human health and damages filters and other vital support systems. Staphylococcus aureus is both a human commensal and an opportunistic pathogen that colonizes human tissues and causes acute and chronic infections. Virulence and colonization factors are positively and negatively regulated, respectively, by bacterial cell-to-cell communication (quorum sensing) via the agr (accessory gene regulator) system. When cultured under low-shear modelled microgravity conditions (LSMMG), S. aureus has been reported to maintain a colonization rather than a pathogenic phenotype. Here, we show that the modulation of agr expression via reduced production of autoinducing peptide (AIP) signal molecules was responsible for this behavior. In an LSMMG environment, the S. aureus strains JE2 (methicillin-resistant) and SH1000 (methicillin-sensitive) both exhibited reduced cytotoxicity towards the human leukemia monocytic cell line (THP-1) and increased fibronectin binding. Using S. aureus agrP3::lux reporter gene fusions and mass spectrometry to quantify the AIP concentrations, the activation of agr, which depends on the binding of AIP to the transcriptional regulator AgrC, was delayed in the strains with an intact autoinducible agr system. This was because AIP production was reduced under these growth conditions compared with the ground controls. Under LSMMG, S. aureus agrP3::lux reporter strains that cannot produce endogenous AIPs still responded to exogenous AIPs. Provision of exogenous AIPs to S. aureus USA300 during microgravity culture restored the cytotoxicity of culture supernatants for the THP-1 cells. These data suggest that microgravity does not affect AgrC-AIP interactions but more likely the generation of AIPs.


Assuntos
Infecções Estafilocócicas , Ausência de Peso , Humanos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Staphylococcus aureus/metabolismo , Proteínas Quinases/metabolismo , Percepção de Quorum/genética , Regulação para Baixo , Peptídeos/metabolismo , Proteínas de Bactérias/metabolismo
3.
Build Environ ; 240: 110422, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37251109

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2, the virus that causes the coronavirus disease (COVID)-19, is primarily transmitted through respiratory droplets which linger in enclosed spaces, often exacerbated by HVAC systems. Although research to improve HVAC handling of SARS-CoV-2 is progressing, currently installed HVAC systems cause problems because they recirculate air and use ineffective filters against virus. This paper details the process of developing a novel method of eliminating air pollutants and suspended pathogens in enclosed spaces using Photocatalytic Oxidation (PCO) technology. It has been previously employed to remove organic contaminants and compounds from air streams using the irradiation of titanium dioxide (TiO2) surfaces with ultraviolet (UV) lights causing the disintegration of organic compounds by reactions with oxygen (O) and hydroxyl radicals (OH). The outcome was two functional prototypes that demonstrate the operation of PCO-based air purification principle. These prototypes comprise a novel TiO2 coated fibre mop system, which provide very large surface area for UV irradiation. Four commercially accessible materials were used for the construction of the mop: Tampico, Brass, Coco, and Natural synthetic. Two types of UV lights were used: 365 nm (UVA) and 270 nm (UVC). A series of tests were conducted that proved the prototype's functionality and its efficiency in lowering volatile organic compounds (VOCs) and formaldehyde (HCHO). The results shown that a MopFan with rotary mop constructed with Coco fibres and utilising UVC light achieves the best VOC and HCHO purification performance. Within 2 h, this combination lowered HCHO by 50% and VOCs by 23% approximately.

4.
Anal Chem ; 94(26): 9389-9398, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35713879

RESUMO

Macrophages are important immune cells that respond to environmental cues acquiring a range of activation statuses represented by pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes at each end of their spectrum. Characterizing the metabolic signature (metabolic profiling) of different macrophage subsets is a powerful tool to understand the response of the human immune system to different stimuli. Here, the recently developed 3D OrbiSIMS instrument is applied to yield useful insight into the metabolome from individual cells after in vitro differentiation of macrophages into naïve, M1, and M2 phenotypes using different cytokines. This analysis strategy not only requires more than 6 orders of magnitude less sample than traditional mass spectrometry approaches but also allows the study of cell-to-cell variance. Characteristic metabolites in macrophage subsets are identified using a targeted lipid and data-driven multivariate approach highlighting amino acids and other small molecules. The diamino acids alanylasparagine and lipid sphingomyelin SM(d18/16:0) are uniquely found in M1 macrophages, while pyridine and pyrimidine are observed at increased intensity in M2 macrophages, findings which link to known biological pathways. The first demonstration of this capability illustrates the great potential of direct cell analysis for in situ metabolite profiling with the 3D OrbiSIMS to probe functional phenotype at the single-cell level using molecular signatures and to understand the response of the human body to implanted devices and immune diseases.


Assuntos
Macrófagos , Metabolômica , Citocinas/metabolismo , Lipídeos , Macrófagos/metabolismo , Fenótipo
5.
J Immunol ; 203(1): 148-157, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31118225

RESUMO

MicroRNAs are small, noncoding RNAs that function as posttranscriptional modulators of gene expression by binding target mRNAs and inhibiting translation. They are therefore crucial regulators of several biological as well as immunological events. Recently, miR-511-3p has been implicated in the development and differentiation of APCs, such as dendritic cells (DCs), and regulating several human diseases. Interestingly, miR-511-3p is embedded within the human MRC1 gene that encodes the mannose receptor. In this study, we sought to examine the impact of miR-511-3p up- or downregulation on human DC surface phenotype, cytokine profile, immunogenicity (using IDO activity as a surrogate), and downstream T cell polarization. Using gene silencing and a selection of microRNA mimics, we could successfully suppress or induce the expression of miR-511-3p in DCs. Consequently, we show for the first time, to our knowledge, that inhibition and/or overexpression of miR-511-3p has opposing effects on the expression levels of two key C-type lectin receptors, namely the mannose receptor and DC-specific ICAM 3 nonintegrin at protein and mRNA levels, thereby affecting C-type lectin receptor-induced modulation of IDO activity in DCs. Furthermore, we show that downregulation of miR-511-3p drives an anti-inflammatory DC response characterized by IL-10 production. Interestingly, the miR-511-3plow DCs also promoted IL-4 secretion and suppressed IL-17 in cocultures with autologous T cells. Together, our data highlight the potential role of miR-511 in regulating DC function and downstream events leading to Th polarization and immune modulation.


Assuntos
Células Dendríticas/fisiologia , Lectinas Tipo C/metabolismo , MicroRNAs/genética , Linfócitos T Auxiliares-Indutores/imunologia , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Regulação da Expressão Gênica , Humanos , Imunomodulação , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Molécula 3 de Adesão Intercelular/genética , Molécula 3 de Adesão Intercelular/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Ativação Linfocitária , RNA Interferente Pequeno/genética , Receptor Cross-Talk
6.
Metabolomics ; 16(3): 33, 2020 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-32114632

RESUMO

INTRODUCTION: Macrophages constitute a heterogeneous population of functionally distinct cells involved in several physiological and pathological processes. They display remarkable plasticity by changing their phenotype and function in response to environmental cues representing a spectrum of different functional phenotypes. The so-called M1 and M2 macrophages are often considered as representative of pro- and anti-inflammatory ends of such spectrum. Metabolomics approach is a powerful tool providing important chemical information about the cellular phenotype of living systems, and the changes in their metabolic pathways in response to various perturbations. OBJECTIVES: This study aimed to characterise M1 and M2 phenotypes in THP-1 macrophages in order to identify characteristic metabolites of each polarisation state. METHODS: Herein, untargeted liquid chromatography (LC)-mass spectrometry (MS)-based metabolite profiling was applied to characterise the metabolic profile of M1-like and M2-like THP-1 macrophages. RESULTS: The results showed that M1 and M2 macrophages have distinct metabolic profiles. Sphingolipid and pyrimidine metabolism was significantly changed in M1 macrophages whereas arginine, proline, alanine, aspartate and glutamate metabolism was significantly altered in M2 macrophages. CONCLUSION: This study represents successful application of LC-MS metabolomics approach to characterise M1 and M2 macrophages providing functional readouts that show unique metabolic signature for each phenotype. These data could contribute to a better understanding of M1 and M2 functional properties and could pave the way for developing new therapeutics targeting different immune diseases.


Assuntos
Macrófagos/metabolismo , Biomarcadores/metabolismo , Cromatografia Líquida , Humanos , Ativação de Macrófagos , Espectrometria de Massas , Metabolômica , Análise Multivariada , Células THP-1
7.
Cell Commun Signal ; 18(1): 120, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746854

RESUMO

Malignant gliomas are the most common and deadly type of central nervous system tumors. Despite some advances in treatment, the mean survival time remains only about 1.25 years. Even after surgery, radiotherapy and chemotherapy, gliomas still have a poor prognosis. Exosomes are the most common type of extracellular vesicles with a size range of 30 to 100 nm, and can act as carriers of proteins, RNAs, and other bioactive molecules. Exosomes play a key role in tumorigenesis and resistance to chemotherapy or radiation. Recent evidence has shown that exosomal microRNAs (miRNAs) can be detected in the extracellular microenvironment, and can also be transferred from cell to cell via exosome secretion and uptake. Therefore, many recent studies have focused on exosomal miRNAs as important cellular regulators in various physiological and pathological conditions. A variety of exosomal miRNAs have been implicated in the initiation and progression of gliomas, by activating and/or inhibiting different signaling pathways. Exosomal miRNAs could be used as therapeutic agents to modulate different biological processes in gliomas. Exosomal miRNAs derived from mesenchymal stem cells could also be used for glioma treatment. The present review summarizes the exosomal miRNAs that have been implicated in the pathogenesis, diagnosis and treatment of gliomas. Moreover, exosomal proteins could also be involved in glioma pathogenesis. Exosomal miRNAs and proteins could also serve as non-invasive biomarkers for prognosis and disease monitoring. Video Abstract.


Assuntos
Exossomos/metabolismo , Glioma/diagnóstico , Glioma/genética , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MicroRNAs/genética
8.
J Cell Biochem ; 120(10): 16352-16361, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31219202

RESUMO

Blood vessels rupture or occlusion in brain results in stroke. Stroke is the major reason for mortality and dysfunction worldwide. Despite several attempts, there are no any approved therapeutic approaches for stroke subjects. The most neuroprotective agents showed the positive effects in preclinical reports, while there are no significant therapeutic impacts in the clinical trials. MicroRNAs (miRNAs) are small noncoding RNAs which involved in the modulation of a variety of cellular and molecular pathways. Given that deregulation of these molecules is related to initiation and progression of stroke. Exosomes are nano-carriers which are able to transfer different cargos such as miRNAs to recipient cells. Increasing evidence revealed that exosomal miRNAs are one of very important factors which are involved in the pathogenesis of stroke. Hence, more understanding about the role of exosomal miRNAs in stroke pathogenesis could contribute in discovering and developing new therapeutic approaches. Moreover, it has been proved the exosomal miRNAs could be used as noninvasive biomarkers in diagnosis and monitoring response to therapy in subjects with stroke. Herein for first time, we summarized different exosomal miRNAs involved in pathogenesis of stroke.


Assuntos
MicroRNA Circulante/sangue , Exossomos/metabolismo , Acidente Vascular Cerebral/sangue , Biomarcadores/sangue , Exossomos/patologia , Humanos , Acidente Vascular Cerebral/patologia
9.
Biotechnol Lett ; 41(1): 1-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30368691

RESUMO

Bioreactors hold a lot of promise for tissue engineering and regenerative medicine applications. They have multiple uses including cell cultivation for therapeutic production and for in vitro organ modelling to provide a more physiologically relevant environment for cultures compared to conventional static conditions. Bioreactors are often used in combination with scaffolds as the nutrient flow can enhance oxygen and diffusion throughout the 3D constructs to prevent the formation of necrotic cores. A variety of scaffolds have been fabricated to achieve a structural architecture that mimic native extracellular matrix. Future developments of in vitro models will incorporate the ability to non-invasively monitor the cellular microenvironment to enhance the understanding of in vitro conditions. This review details current advancements in bioreactor and scaffold systems and provides insight on how in vitro models can be augmented for future biomedical applications.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/instrumentação , Engenharia Tecidual/instrumentação , Animais , Técnicas de Cultura de Células/métodos , Humanos , Engenharia Tecidual/métodos
10.
Opt Express ; 26(19): 25211-25225, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30469626

RESUMO

We present a new approach for combining holographic optical tweezers with confocal Raman spectroscopy. Multiple laser foci, generated using a liquid-crystal spatial light modulator, are individually used for both optical trapping and excitation of spontaneous Raman spectroscopy from trapped objects. Raman scattering from each laser focus is spatially filtered using reflective apertures on a digital micro-mirror device, which can be reconfigured with flexible patterns at video rate. We discuss operation of the instrument, and performance and viability considerations for biological measurements. We then demonstrate the capability of the instrument for fast, flexible, and interactive manipulation with molecular measurement of interacting live cell systems.


Assuntos
Bactérias/citologia , Células Dendríticas/citologia , Holografia/instrumentação , Pinças Ópticas , Análise Espectral Raman/instrumentação , Linfócitos T/citologia , Desenho de Equipamento , Luz
11.
Am J Respir Cell Mol Biol ; 56(6): 772-783, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28225294

RESUMO

Fibrosis is a major cause of progressive organ dysfunction in several chronic pulmonary diseases. Rho-associated coiled-coil forming kinase (ROCK) has been shown to be involved in myofibroblast differentiation driven by altered matrix stiffness in a fibrotic state. There are two known ROCK isoforms in humans, ROCK1 and ROCK2, but the specific role of each isoform in myofibroblast differentiation in lung fibrosis remains unknown. To study this, we developed a gelatin methacryloyl hydrogel-based culture system with different stiffness levels relevant to healthy and fibrotic lungs. We have shown that stiff matrix, but not soft matrix, can induce myofibroblast differentiation with high smooth muscle actin isoform (αSMA) expression. Furthermore, our data confirmed that the inhibition of ROCK signaling by a pharmacological inhibitor (i.e., Y27632) attenuates stiffness-induced αSMA expression and fiber assembly in myofibroblasts. To assess the role of ROCK isoforms in this process, we used short interfering RNA to knock down the expression of each isoform. Our data showed that knocking down either ROCK1 or ROCK2 did not result in a reduction in αSMA expression in myofibroblasts on stiff matrix, as opposed to soft matrix, where αSMA expression was reduced significantly. Paradoxically, on stiff matrix, the absence of one isoform (particularly ROCK2) exaggerated αSMA expression and led to thick fiber assembly. Moreover, complete loss of αSMA fiber assembly was seen only in the absence of both ROCK isoforms, suggesting that both isoforms are implicated in this process. Overall, our results indicate the differential role of ROCK isoforms in myofibroblast differentiation on soft and stiff matrices.


Assuntos
Diferenciação Celular , Miofibroblastos/enzimologia , Miofibroblastos/patologia , Fibrose Pulmonar/enzimologia , Fibrose Pulmonar/patologia , Estresse Mecânico , Quinases Associadas a rho/metabolismo , Actinas/metabolismo , Amidas/farmacologia , Fenômenos Biomecânicos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Gelatina/farmacologia , Inativação Gênica/efeitos dos fármacos , Humanos , Hidrogéis/farmacologia , Isoenzimas/metabolismo , Metacrilatos/farmacologia , Polimerização/efeitos dos fármacos , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fibras de Estresse/efeitos dos fármacos , Fibras de Estresse/metabolismo , Especificidade por Substrato/efeitos dos fármacos , Alicerces Teciduais/química , Transativadores/metabolismo
12.
J Immunol ; 194(12): 5761-74, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25980006

RESUMO

CD4(+)CD25(hi) FOXP3(+) regulatory T cells (Tregs) maintain tolerance to self-Ags. Their defective function is involved in the pathogenesis of multiple sclerosis (MS), an inflammatory demyelinating disease of the CNS. However, the mechanisms of such defective function are poorly understood. Recently, we reported that stimulation of TLR2, which is preferentially expressed by human Tregs, reduces their suppressive function and skews them into a Th17-like phenotype. In this study, we tested the hypothesis that TLR2 activation is involved in reduced Treg function in MS. We found that Tregs from MS patients expressed higher levels of TLR2 compared with healthy controls, and stimulation with the synthetic lipopeptide Pam3Cys, an agonist of TLR1/2, reduced Treg function and induced Th17 skewing in MS patient samples more than in healthy controls. These data provide a novel mechanism underlying diminished Treg function in MS. Infections that activate TLR2 in vivo (specifically through TLR1/2 heterodimers) could shift the Treg/Th17 balance toward a proinflammatory state in MS, thereby promoting disease activity and progression.


Assuntos
Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Receptor 2 Toll-Like/metabolismo , Adulto , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Citocinas/biossíntese , Feminino , Humanos , Imunomodulação , Imunofenotipagem , Lipoproteínas/farmacologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/metabolismo , Fator de Transcrição STAT3/metabolismo , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/citologia , Células Th17/citologia , Receptor 2 Toll-Like/agonistas , Adulto Jovem
13.
J Allergy Clin Immunol ; 137(6): 1841-1851.e2, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26703454

RESUMO

BACKGROUND: Dendritic cells (DCs) are key players in the induction and re-elicitation of TH2 responses to allergens. We have previously shown that different C-type lectin receptors on DCs play a major role in allergen recognition and uptake. In particular, mannose receptor (MR), through modulation of Toll-like receptor (TLR) 4 signaling, can regulate indoleamine 2,3-dioxygenase (IDO) activity, favoring TH2 responses. Interestingly, the aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor with an emerging role in immune modulation, has been implicated in IDO activation in response to TLR stimulation. OBJECTIVE: Here we investigated how allergens and lectins modulate the TLR4-AhR-IDO axis in human monocyte-derived DCs. METHODS: Using a combination of genomics, proteomics, and immunologic studies, we investigated the role of MR and AhR in IDO regulation and its effect on T helper cell differentiation. RESULTS: We have demonstrated that LPS induces both IDO isoforms (IDO1 and IDO2) in DCs, with partial involvement of AhR. Additionally, we found that, like mannan, different airborne allergens can effectively downregulate TLR4-induced IDO1 and IDO2 expression, most likely through binding to the MR. Mannose-based ligands were also able to downregulate IL-12p70 production by DCs, affecting T helper cell polarization. Interestingly, AhR and some components of the noncanonical nuclear factor κB pathway were shown to be downregulated after MR engagement, which could explain the regulatory effects of MR on IDO expression. CONCLUSION: Our work demonstrates a key role for MR in the modulation of the TLR4-AhR-IDO axis, which has a significant effect on DC behavior and the development of immune responses against allergens.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Superfície Celular/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Alérgenos/imunologia , Análise por Conglomerados , Citocinas/metabolismo , Perfilação da Expressão Gênica , Humanos , Interleucina-12/biossíntese , Ligantes , Ativação Linfocitária/imunologia , Receptor de Manose , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/metabolismo
14.
Immunology ; 149(4): 413-422, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27502559

RESUMO

Although eosinophils are inflammatory cells, there is increasing attention on their immunomodulatory roles. For example, murine eosinophils can present antigen to CD4+ T helper (Th) cells, but it remains unclear whether human eosinophils also have this ability. This study determined whether human eosinophils present a range of antigens, including allergens, to activate Th cells, and characterized their expression of MHC class II and co-stimulatory molecules required for effective presentation. Human peripheral blood eosinophils purified from non-allergic donors were pulsed with the antigens house dust mite extract (HDM), Timothy Grass extract (TG) or Mycobacterium tuberculosis purified protein derivative (PPD), before co-culture with autologous CD4+ Th cells. Proliferative and cytokine responses were measured, with eosinophil expression of HLA-DR/DP/DQ and the co-stimulatory molecules CD40, CD80 and CD86 determined by flow cytometry. Eosinophils pulsed with HDM, TG or PPD drove Th cell proliferation, with the response strength dependent on antigen concentration. The cytokine responses varied with donor and antigen, and were not biased towards any particular Th subset, often including combinations of pro- and anti-inflammatory cytokines. Eosinophils up-regulated surface expression of HLA-DR/DP/DQ, CD80, CD86 and CD40 in culture, increases that were sustained over 5 days when incubated with antigens, including HDM, or the major allergens it contains, Der p I or Der p II. Human eosinophils can, therefore, act as effective antigen-presenting cells to stimulate varied Th cell responses against a panel of antigens including HDM, TG or PPD, an ability that may help to determine the development of allergic disease.


Assuntos
Eosinófilos/metabolismo , Mycobacterium tuberculosis/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Apresentação de Antígeno , Antígenos de Dermatophagoides/imunologia , Antígenos de Dermatophagoides/metabolismo , Antígenos de Plantas/imunologia , Antígenos de Plantas/metabolismo , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/metabolismo , Células Cultivadas , Técnicas de Cocultura , Cisteína Endopeptidases/imunologia , Cisteína Endopeptidases/metabolismo , Citocinas/metabolismo , Eosinófilos/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Ativação Linfocitária , Phleum , Pyroglyphidae , Tuberculina/imunologia , Tuberculina/metabolismo
15.
Cell Microbiol ; 17(7): 1008-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25600171

RESUMO

Neisseria meningitidis, a major cause of bacterial meningitis and septicaemia, secretes multiple virulence factors, including the adhesion and penetration protein (App) and meningococcal serine protease A (MspA). Both are conserved, immunogenic, type Va autotransporters harbouring S6-family serine endopeptidase domains. Previous work suggested that both could mediate adherence to human cells, but their precise contribution to meningococcal pathogenesis was unclear. Here, we confirm that App and MspA are in vivo virulence factors since human CD46-expressing transgenic mice infected with meningococcal mutants lacking App, MspA or both had improved survival rates compared with mice infected with wild type. Confocal imaging showed that App and MspA were internalized by human cells and trafficked to the nucleus. Cross-linking and enzyme-linked immuno assay (ELISA) confirmed that mannose receptor (MR), transferrin receptor 1 (TfR1) and histones interact with MspA and App. Dendritic cell (DC) uptake could be blocked using mannan and transferrin, the specific physiological ligands for MR and TfR1, whereas in vitro clipping assays confirmed the ability of both proteins to proteolytically cleave the core histone H3. Finally, we show that App and MspA induce a dose-dependent increase in DC death via caspase-dependent apoptosis. Our data provide novel insights into the roles of App and MspA in meningococcal infection.


Assuntos
Apoptose , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/metabolismo , Histonas/metabolismo , Interações Hospedeiro-Patógeno , Neisseria meningitidis/patogenicidade , Sistemas de Secreção Tipo V/metabolismo , Fatores de Virulência/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Sobrevivência Celular , Células Cultivadas , Células Dendríticas/microbiologia , Células Dendríticas/fisiologia , Modelos Animais de Doenças , Humanos , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/patologia , Camundongos Transgênicos , Proteólise , Análise de Sobrevida
16.
Biomacromolecules ; 17(6): 2189-98, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27183396

RESUMO

This study aims to design an optimal polyelectrolyte multilayer film of poly-l-lysine (PLL) and hyaluronic acid (HA) as an anti-inflammatory cytokine release system in order to decrease the implant failure due to any immune reactions. The chemical modification of the HA with aldehyde moieties allows self-cross-linking of the film and an improvement in the mechanical properties of the film. The cross-linking of the film and the release of immunomodulatory cytokine (IL-4) stimulate the differentiation of primary human monocytes seeded on the films into pro-healing macrophages phenotype. This induces the production of anti-inflammatory cytokines (IL1-RA and CCL18) and the decrease of pro-inflammatory cytokines secreted (IL-12, TNF-α, and IL-1ß). Moreover, we demonstrate that cross-linking PLL/HA film using HA-aldehyde is already effective by itself to limit inflammatory processes. Finally, this functionalized self-cross-linked PLL/HA-aldehyde films constitutes an innovative and efficient candidate for immunomodulation of any kind of implants of various architecture and properties.


Assuntos
Reagentes de Ligações Cruzadas/química , Citocinas/administração & dosagem , Ácido Hialurônico/química , Imunomodulação/efeitos dos fármacos , Inflamação/tratamento farmacológico , Polieletrólitos/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/química , Humanos , Inflamação/imunologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Propriedades de Superfície
17.
Respir Res ; 16: 144, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26619903

RESUMO

BACKGROUND: Inflammatory respiratory diseases are amongst major global health challenges. Lung fibroblasts have been shown to play a key role in lung inflammatory responses. However, their exact role in initiation and maintenance of lung diseases has remained elusive partly due to the limited availability of physiologically relevant in vitro models. Therefore, developing new tools that enable investigating the molecular pathways (e.g. nuclear factor-kappa B (NF-κB) activation) that underpin inflammatory responses in fibroblasts could be a valuable resource for scientists working in this area of research. RESULTS: In order to investigate NF-κB activation in response to pro-inflammatory stimuli in real-time, we first developed two detection systems based on nuclear localization of NF-κB by immunostaining and luciferase reporter assay system. Furthermore using electrospun porous scaffolds, with similar geometry to human lung extracellular matrix, we developed 3D cultures of lung fibroblasts allowing comparing NF-κB activation in response to pro-inflammatory stimuli (i.e. TNF-α) in 2D and 3D. Our data clearly show that the magnitude of NF-κB activation in 2D cultures is substantially higher than 3D cultures. However, unlike 2D cultures, cells in the 3D model remained responsive to TNF-α at higher concentrations. The more subdued and wider dynamic range of NF-κB responses in 3D culture system was associated with a different expression pattern for TNF receptor I in 3D versus 2D cultures collectively reflecting a more in vivo like TNF receptor I expression and NF-κB activation pattern in the 3D system. CONCLUSION: Our data suggest that lung fibroblasts are actively involved in the pathogenesis of lung inflammation by activation of NF-κB signaling pathway. The 3D culture detection system provides a sensitive and biologically relevant tool for investigating different pro-inflammatory events involving lung fibroblasts.


Assuntos
Técnicas de Cultura de Células , Fibroblastos/metabolismo , Mediadores da Inflamação/metabolismo , Pulmão/metabolismo , Pneumonia/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Genes Reporter , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pneumonia/patologia , Receptores Tipo I de Fatores de Necrose Tumoral/agonistas , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Transcrição RelA/genética , Transfecção , Fator de Necrose Tumoral alfa/farmacologia
18.
Mol Pharm ; 11(7): 2082-91, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24628276

RESUMO

The development of more complex in vitro models for the assessment of novel drugs and chemicals is needed because of the limited biological relevance of animal models to humans as well as ethical considerations. Although some human-cell-based assays exist, they are usually 2D, consist of single cell type, and have limited cellular and functional representation of the native tissue. In this study, we have used biomimetic porous electrospun scaffolds to develop an immunocompetent 3D model of the human respiratory tract comprised of three key cell types present in upper airway epithelium. The three cell types, namely, epithelial cells (providing a physical barrier), fibroblasts (extracellular matrix production), and dendritic cells (immune sensing), were initially grown on individual scaffolds and then assembled into the 3D multicell tissue model. The epithelial layer was cultured at the air-liquid interface for up to four weeks, leading to formation of a functional barrier as evidenced by an increase in transepithelial electrical resistance (TEER) and tight junction formation. The response of epithelial cells to allergen exposure was monitored by quantifying changes in TEER readings and by assessment of cellular tight junctions using immunostaining. It was found that epithelial cells cocultured with fibroblasts formed a functional epithelial barrier at a quicker rate than single cultures of epithelial cells and that the recovery from allergen exposure was also more rapid. Also, our data show that dendritic cells within this model remain viable and responsive to external stimulation as evidenced by their migration within the 3D construct in response to allergen challenge. This model provides an easy to assemble and physiologically relevant 3D model of human airway epithelium that can be used for studies aiming at better understanding lung biology, the cross-talk between immune cells, and airborne allergens and pathogens as well as drug delivery.


Assuntos
Avaliação de Medicamentos/métodos , Preparações Farmacêuticas/administração & dosagem , Mucosa Respiratória/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Alérgenos/administração & dosagem , Biomimética/métodos , Linhagem Celular , Técnicas de Cocultura/métodos , Células Dendríticas/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Junções Íntimas/efeitos dos fármacos , Alicerces Teciduais
19.
J Allergy Clin Immunol ; 132(1): 27-36, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23534971

RESUMO

Allergic diseases are a global public health issue affecting millions of persons around the world. However, full understanding of the molecular basis of this group of chronic inflammatory disorders remains rather elusive. Recently, the role of carbohydrates on allergens and their counterstructures on antigen-presenting cells (lectins) have been highlighted as crucial factors in allergen sensitization, which culminates in TH2 cell differentiation and the production of deleterious specific IgE antibodies. Here we review recent progress on the role of different lectins in patients with type I hypersensitivity or allergy, their interplay with other determinants of allergenicity, and ways of developing therapeutic modalities against newly identified targets.


Assuntos
Hipersensibilidade/etiologia , Lectinas/fisiologia , Animais , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/fisiologia , Galectinas/química , Galectinas/fisiologia , Glicosilação , Humanos , Imunoterapia , Lectinas Tipo C/química , Lectinas Tipo C/fisiologia , Receptor de Manose , Lectinas de Ligação a Manose/química , Lectinas de Ligação a Manose/fisiologia , Receptores de Superfície Celular/química , Receptores de Superfície Celular/fisiologia , Receptores Toll-Like/fisiologia
20.
Bio Protoc ; 14(4): e4939, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405080

RESUMO

Biomaterials are designed to interact with biological systems to replace, support, enhance, or monitor their function. However, there are challenges associated with traditional biomaterials' development due to the lack of underlying theory governing cell response to materials' chemistry. This leads to the time-consuming process of testing different materials plus the adverse reactions in the body such as cytotoxicity and foreign body response. High-throughput screening (HTS) offers a solution to these challenges by enabling rapid and simultaneous testing of a large number of materials to determine their bio-interactions and biocompatibility. Secreted proteins regulate many physiological functions and determine the success of implanted biomaterials through directing cell behaviour. However, the majority of biomaterials' HTS platforms are suitable for microscopic analyses of cell behaviour and not for investigating non-adherent cells or measuring cell secretions. Here, we describe a multi-well platform adaptable to robotic printing of polymers and suitable for secretome profiling of both adherent and non-adherent cells. We detail the platform's development steps, encompassing the preparation of individual cell culture chambers, polymer printing, and the culture environment, as well as examples to demonstrate surface chemical characterisation and biological assessments of secreted mediators. Such platforms will no doubt facilitate the discovery of novel biomaterials and broaden their scope by adapting wider arrays of cell types and incorporating assessments of both secretome and cell-bound interactions. Key features • Detailed protocols for preparation of substrate for contact printing of acrylate-based polymers including O2 plasma etching, functionalisation process, and Poly(2-hydroxyethyl methacrylate) (pHEMA) dip coating. • Preparations of 7 mm × 7 mm polymers employing pin printing system. • Provision of confined area for each polymer using ProPlate® multi-well chambers. • Compatibility of this platform was validated using adherent cells [primary human monocyte-derived macrophages (MDMs)) and non-adherent cells (primary human monocyte-derived dendritic cells (moDCs)]. • Examples of the adaptability of the platform for secretome analysis including five different cytokines using enzyme-linked immunosorbent assay (ELISA, DuoSet®). Graphical overview.

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