Letteratura scientifica selezionata sul tema "A549-Thp-1"

Epithelial–mesenchymal transition (EMT) plays a key role in the process of pulmonary fibrosis (PF). Increasing evidences have shown that exaggerated EMT in recurrent pulmonary injury mediates the early pathogenesis of PF. This study aimed to evaluate EMT of human alveolar epithelial cells (A549) when cocultured with human macrophages Tohoku hospital pediatrics-1 (THP-1) induced by lipopolysaccharide (LPS) and investigate the role of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Firstly, we detected the inflammatory and EMT biomarkers in A549 cells monoculture and A549/THP-1 cells coculture in the presence or absence of LPS. Then, the activation of JAK2/STAT3 signaling pathway was determined in coculture. Interestingly, inflammatory markers, such as interleukin (IL)-6, matrix metalloproteinase (MMP)-9, transforming growth factor (TGF)- β, and collagen type 1 (COL-1), were enhanced in LPS treated coculture. Besides, the expression of E-cadherin decreased but α-smooth muscle actin expression increased, indicating the presence of EMT in A549 cells when cocultured with THP-1 macrophages. However, these phenotypes could not be observed in LPS-treated A549 cells monoculture. Meanwhile, JAK2/STAT3 signaling pathway was activated, and the STAT3 DNA-binding and inflammatory markers were inhibited by Stattic. Together, these findings demonstrate the key role of JAK2/STAT3 signaling pathway in LPS promoted EMT of A549 in the presence of THP-1 macrophages as an in vitro PF model.

ABSTRACT The Streptococcus pneumoniae pore-forming toxin, pneumolysin, is an important virulence factor in pneumococcal pneumonia. The effect of pneumolysin on human lung epithelial and monocyte cell viability was compared. Pneumolysin caused a dose-dependent loss of viability of human lung epithelial (A549 and L132) and monocyte (U937 and THP-1) cell lines. Analysis of the dose-response curves revealed similar log 50% inhibitory concentration (pIC50) values for A549, L132, and THP-1 of 0.12± 0.1, 0.02± 0.04, and 0.12± 0.13 hemolytic units (HU), respectively, but U937 cells showed a significantly greater pIC50 of 0.42± 0.12 HU. Differentiation of A549 and L132 with phorbol ester or THP-1 with gamma interferon had no effect on their sensitivity to pneumolysin. However, a significant decrease in the potency of pneumolysin against U937 cells followed gamma interferon treatment. The Hill slopes of the inhibition curves were greater than unity, indicating that pneumolysin may act with positive cooperativity. Analysis of pneumolysin-treated THP-1 cells by electron microscopy revealed membrane lesions of between 100 and 200 nm in diameter.

Background: Neuregulin (NRG)-1-human epidermal receptor (HER)-2 signaling pathway is a key regulator of IL-1β-mediated pulmonary inflammation and epithelial permeability. The inflammasome is a newly discovered molecular platform required for caspase-1 activation and maturation of IL-1β. However, the role of the inflammasome in NRG-1-HER2 signaling-mediated alveolar cell permeability is unknown. Methods: The inflammasome was activated or inhibited in THP-1 cells; supernatants from these cells were added to A549 cells and human small airway epithelial cells (HSAEC). The protein expression of NRG-1 and phospho-HER2 (pHER2) were measured by Western blot analysis and epithelial permeability was measured using Lucifer yellow dye. Results: Results reveal that alveolar permeability in A549 cells and HSAEC is increased when treated with supernatants of inflammasome-activated THP-1 cells. Alveolar permeability is significantly suppressed when treated with supernatant of inflammasome-inhibited THP-1 cells. Inflammasome-mediated permeability is decreased when A549 cells and HSAEC are pretreated with IL-1β receptor antagonist (IL-1βRA). In addition, HER2 kinase inhibitor AG825 or NRG-1 inhibitor TAPI inhibits inflammasome-mediated permeability in A549 cells and HSAEC demonstrating critical roles of IL-1β, NRG-1, and HER2 in inflammasome-mediated alveolar permeability. Conclusion: These findings suggest that inflammasome-induced alveolar cell permeability is mediated by NRG-1/HER2 signaling through IL-1β regulation.

The most common Aspergilli isolated from indoor air samples from occupied buildings and a grain mill were extracted and analyzed for their combined (Flavi + Nigri, Versicolores + Nigri) cytotoxic, genotoxic and pro-inflammatory properties on human adenocarcinoma cells (A549) and monocytic leukemia cells induced in macrophages (THP-1 macrophages). Metabolite mixtures from the Aspergilli series Nigri increase the cytotoxic and genotoxic potency of Flavi extracts in A549 cells suggesting additive and/or synergistic effects, while antagonizing the cytotoxic potency of Versicolores extracts in THP-1 macrophages and genotoxicity in A549 cells. All tested combinations significantly decreased IL-5 and IL-17, while IL-1β, TNF-α and IL-6 relative concentrations were increased. Exploring the toxicity of extracted Aspergilli deepens the understanding of intersections and interspecies differences in events of chronic exposure to their inhalable mycoparticles.

Respiratory exposure of humans to environmental and therapeutic nanoparticles repeatedly occurs at relatively low concentrations. To identify adverse effects of particle accumulation under realistic conditions, monocultures of Calu-3 and A549 cells and co-cultures of A549 and THP-1 macrophages in the air–liquid interphase culture were exposed repeatedly to 2 µg/cm2 20 nm and 200 nm polystyrene particles with different functionalization. Particle accumulation, transepithelial electrical resistance, dextran (3–70 kDa) uptake and proinflammatory cytokine secretion were determined over 28 days. Calu-3 cells showed constant particle uptake without any change in barrier function and cytokine release. A549 cells preferentially ingested amino- and not-functionalized particles combined with decreased endocytosis. Cytokine release was transiently increased upon exposure to all particles. Carboxyl-functionalized demonstrated higher uptake and higher cytokine release than the other particles in the A549/THP-1 co-cultures. The evaluated respiratory cells and co-cultures ingested different amounts and types of particles and caused small (partly transient) effects. The data suggest that the healthy cells can adapt to low doses of non-cytotoxic particles.

ABSTRACT The clinical picture of severe acute respiratory syndrome (SARS) is characterized by pulmonary inflammation and respiratory failure, resembling that of acute respiratory distress syndrome. However, the events that lead to the recruitment of leukocytes are poorly understood. To study the cellular response in the acute phase of SARS coronavirus (SARS-CoV)-host cell interaction, we investigated the induction of chemokines, adhesion molecules, and DC-SIGN (dendritic cell-specific ICAM-3-grabbing nonintegrin) by SARS-CoV. Immunohistochemistry revealed neutrophil, macrophage, and CD8 T-cell infiltration in the lung autopsy of a SARS patient who died during the acute phase of illness. Additionally, pneumocytes and macrophages in the patient's lung expressed P-selectin and DC-SIGN. In in vitro study, we showed that the A549 and THP-1 cell lines were susceptible to SARS-CoV. A549 cells produced CCL2/monocyte chemoattractant protein 1 (MCP-1) and CXCL8/interleukin-8 (IL-8) after interaction with SARS-CoV and expressed P-selectin and VCAM-1. Moreover, SARS-CoV induced THP-1 cells to express CCL2/MCP-1, CXCL8/IL-8, CCL3/MIP-1α, CXCL10/IP-10, CCL4/MIP-1β, and CCL5/RANTES, which attracted neutrophils, monocytes, and activated T cells in a chemotaxis assay. We also demonstrated that DC-SIGN was inducible in THP-1 as well as A549 cells after SARS-CoV infection. Our in vitro experiments modeling infection in humans together with the study of a lung biopsy of a patient who died during the early phase of infection demonstrated that SARS-CoV, through a dynamic interaction with lung epithelial cells and monocytic cells, creates an environment conducive for immune cell migration and accumulation that eventually leads to lung injury.

Air pollutants of PM2.5 can alter the composition of gut microbiota and lead to inflammation in the lung and gastrointestinal tract. The aim of this study was to evaluate the protective effect of a novel herbal extract blend, FC, composed of Lonicera japonica extract, Momordica grosvenori extract, and broccoli seed extract, on PM2.5-induced inflammation in the respiratory and intestinal tract. A549 cells and THP-1 cells, as well as C57BL/6 mice, were stimulated with PM2.5 to establish in vitro and in vivo exposure models. The models were treated with or without FC. The expression of inflammatory cytokines and tight junction proteins were studied. Proteomic analysis was performed to elucidate mechanisms. Mouse feces were collected for gut microbiota analysis. FC was shown to modulate the upregulation of pro-inflammatory cytokines mRNA expression in A549 and THP-1 cells and downregulated tight junction proteins mRNA expression in A549 cells due to PM2.5 stimulation. In animal models, the decreased expression of the anti-inflammatory factor il-10, tight junction protein ZO-1, and the elevated expression of COX-2 induced by PM2.5 were improved by FC intervention, which may be associated with zo-1 and cox-2 signaling pathways. In addition, FC was shown to improve the gut microbiota by increasing the abundance of beneficial bacteria.

Introduction. The biological functions of neutrophil extracellular traps (NETs) in tumorigenesis have drawn an increasing amount of attention. This study explored the relationship between NETs and the inflammatory microenvironment in lung cancer cell invasion and metastasis. Methods. NETs were quantified using myeloperoxidase (MPO–DNA) and immunofluorescence staining. Cytokine levels were measured using ELISA kits. THP-1 and A549 cells were used for in vitro experiments. Transwell and Matrigel assays were used to assess the invasion and migration abilities of the cells. Results. Neutrophil infiltration and NET formation were observed in the lung cancer tissues. Compared with healthy controls, the level of MPO–DNA complexes in lung cancer patients increased remarkably and was positively correlated with peripheral blood neutrophil counts, smoking status, and poor prognosis. Increased circulating NET levels were also positively correlated with the levels of inflammatory cytokines, including IL-1β, IL-6, IL-18, and TNF-α. Neutrophils isolated from patients with lung cancer are more prone to NET release. NETs can promote the invasion and migration ability of THP-1 and A549 cell in coculture systems, while pretreatment with NET inhibitors can effectively reduce NET-induced invasion and metastasis. The ability of NETs to promote invasion and metastasis is partly dependent on macrophages. Conclusion. Taken together, our study demonstrated that NETs facilitate A549 cell invasion and migration in a macrophage-maintained inflammatory microenvironment.

In this work, bulb extracts of Tigridia vanhouttei were obtained by maceration with solvents of increasing polarity. The extracts were evaluated against a panel of pathogenic bacterial and fungal strains using the minimal inhibitory concentration (MIC) assay. The cytotoxicity of the extracts was tested against two cell lines (THP-1 and A549) using the MTT assay. The anti-inflammatory activity of the extracts was evaluated in THP-1 cells by measuring the secretion of pro-inflammatory (IL-6 and TNF-α) and anti-inflammatory (IL-10) cytokines by ELISA. The chemical composition of the extracts was recorded by FTIR spectroscopy, and their chemical profiles were evaluated using GC-MS. The results revealed that only hexane extract inhibited the growth of the clinical isolate of Pseudomonas aeruginosa at 200 μg/mL. Against THP-1 cells, hexane and chloroform extracts were moderately cytotoxic, as they exhibited LC50 values of 90.16, and 46.42 μg/mL, respectively. Treatment with methanol extract was weakly cytotoxic at LC50 443.12 μg/mL against the same cell line. Against the A549 cell line, hexane, chloroform, and methanol extracts were weakly cytotoxic because of their LC50 values: 294.77, 1472.37, and 843.12 μg/mL. The FTIR analysis suggested the presence of natural products were confirmed by carboxylic acids, ketones, hydroxyl groups, or esters. The GC-MS profile of extracts revealed the presence of phytosterols, tetracyclic triterpenes, multiple fatty acids, and sugars. This report confirms the antimicrobial, cytotoxic, and anti-inflammatory activities of T. vanhouttei.

La toxicité des fumées issues de compositions pyrotechniques (fumigènes), utilisés notamment par les forces armées, est une préoccupation majeure tant pour les fabricants que pour les utilisateurs. En conséquence, une évaluation des dangers liés à l'inhalation de ces fumées (en particulier au niveau pulmonaire) doit être réalisée. Cette évaluation est jusqu'à présent réalisée via des tests expérimentaux nécessitant des essais sur animaux, qui posent des questions éthiques et qui peuvent entraîner des coûts et délais considérables. Par ailleurs, le développement de nouvelles formulations pyrotechniques exige un investissement significatif en recherche et développement avant d'atteindre des niveaux de performance et de sécurité adéquats pour la qualification et la commercialisation.Dans ce contexte, l'adoption de méthodes alternatives in vitro pour anticiper la toxicité des fumées des nouvelles formulations devient cruciale. Cela afin de diminuer le temps et les coûts des essais, tout en évaluant la toxicité potentielle dès les premières phases de R&D, orientant ainsi le développement vers des formulations moins nocives.L'objectif de cette thèse a donc été d'évaluer l'utilisation de modèles in vitro comme alternative à l'expérimentation animale pour caractériser la toxicité aiguë pulmonaire des fumées issues de fumigènes.La première partie du travail de thèse a consisté à choisir un modèle cellulaire pulmonaire à utiliser et à mettre au point. Les paramètres expérimentaux (le support de culture ou encore le débit d'exposition) pour exposer les cellules de la co-culture A549-THP1 choisie aux fumées générées par la combustion de compositions fumigènes ont été optimisés. Dans un second temps, une fois les paramètres expérimentaux définis, une campagne d'essai portant sur 12 formulations de fumigènes et 2 blancs a été menée sur le modèle cellulaire choisi : une co-culture de cellules alvéolaire A549 - THP-1 à l'interface air-liquide (ALI) a été exposée aux fumées issues de fumigènes présentant a priori des niveaux de toxicité différents dans un système de type Vitrocell® (système dynamique) simultanément à l'exposition de rats aux mêmes fumées. Le modèle in vitro s'est révélé en adéquation avec les attendus de ces premiers essais. Dans le cadre de la thèse, le potentiel in vitro cytotoxique, inflammatoire et oxydatif des fumées a été mesuré 24h après exposition. Les réponses in vitro observées ont été comparées aux données in vivo, obtenues en marge de la thèse, par la réalisation de corrélations vivo-vitro. Des corrélations ont été montrées pour les familles HC pour la viabilité et la famille X pour l'inflammation.En conclusion, nos résultats ont facilité l'établissement d'une méthodologie appropriée pour l'évaluation de la toxicité aiguë par inhalation. Ils soulignent l'importance de continuer à développer des modèles in vitro ou des batteries de tests pour cette évaluation en gardant comme objectif de s'aligner au plus près des modèles in vivo tout en conservant une approche standardisée
The toxicity of fumes from pyrotechnic devices particularly used by armed forces, is a significant concern for both manufacturers and users. Consequently, a danger assessment especially at the pulmonary level related to the inhalation of these fumes must be conducted. So far, this evaluation has been carried out via experimental tests requiring animal trials, which raise ethical concerns and can lead to substantial costs and delays. Moreover, the development of new pyrotechnic formulations demands significant investment in research and development before achieving adequate levels of performance and safety for qualification and commercialization.In this context, the adoption of alternative in vitro methods to anticipate the toxicity of fumes from new formulations becomes crucial to reduce the time and costs of trials while assessing potential toxicity from the early stages of R&D, thus guiding development towards less harmful formulations.The aim of this thesis was to evaluate the use of in vitro models as an alternative to animal experimentation to characterize the acute pulmonary toxicity of fume from pyrotechnic devices.The first part of the thesis work involved the pulmonary cell model selection, which is the A549-THP-1 co-culture, and developing the experimental parameters to expose the cells to fume generated by the combustion of pyrotechnic compositions. Culture support and exposure flow rate were optimized. Subsequently, once the experimental parameters were defined, a test campaign on 12 pyrotechnic formulations and 2 blanks was conducted on the chosen cell model: an A549-THP-1 alveolar cell co-culture at the air-liquid interface (ALI) was exposed to fume with presumably different levels of toxicity in a Vitrocell® type system (dynamic system) simultaneously with the exposure of rats to the same fume. The in vitro model proved predictive of these initial trials. As part of the thesis, the in vitro cytotoxic, inflammatory, and oxidative potential of the fumes was measured 24 hours after exposure. The in vitro responses observed were compared with in vivo data, obtained alongside the thesis, by making vivo-vitro correlations and showed concordances for the HC family viability and the X family inflammation.In conclusion, our results facilitated the establishment of an appropriate methodology for the assessment of acute inhalation toxicity. They underscore the importance of keeping on developing in vitro models or test batteries for this evaluation, with the goal of aligning as closely as possible with in vivo models while maintaining a standardized approach

Après exposition par inhalation, les nanoparticules (NPs) peuvent atteindre les alvéoles pulmonaires, se retrouver au niveau de la barrière alvéolo-capillaire (BAC), et induire une toxicité locale et / ou franchir cette barrière pour se retrouver dans la circulation sanguine. Dans ce contexte, l’objectif de ce travail a été de développer des modèles de co-cultures in vitro simples à mettre en œuvre (utilisation de lignées cellulaires humaines), pour étudier les effets des NPs au niveau de la BAC. Dans un premier temps, des co-cultures de cellules épithéliales alvéolaires ou de phénotype proche (lignées A549 ou NCI-H441), et de macrophages (lignée THP-1), ont permis l’étude des effets pro-inflammatoires des NPs de SiO2 et de TiO2. Avec ces modèles nous avons montré l’importance de la coopération cellulaire mise en jeu lors des processus inflammatoires liés aux NPs, mais aussi le rôle du ratio cellulaire employé dans ces réponses. Dans un second temps, des co-cultures tridimensionnelles en chambres bicamérales associant des macrophages (lignée THP-1), des cellules épithéliales bronchiques (lignée Calu-3), et des cellules endothéliales pulmonaires microvasculaires (lignée HPMEC-ST1.6R), ont permis l’étude de l’impact de NPs fluorescentes de polystyrène sur l’intégrité de la BAC, et leur passage à travers cette barrière. Les cellules épithéliales Calu-3 permettent d’établir une barrière de qualité mais la membrane microporeuse servant de support aux cellules doit être optimisée pour ne pas être un frein au passage des NPs. Ce travail montre qu’un seul modèle ne permet pas d’étudier de façon optimale à la fois la toxicité et la translocation des NPs, et qu’une approche adaptée doit être envisagée en fonction du paramètre que l’on souhaite étudier
After inhalation, nanoparticles (NPs) can reach the alveoli and the alveolo-capillary barrier (ACB), and consequently induce local toxicity and / or cross this barrier to reach the bloodstream. In this context, the aim of this work was to develop co-culture in vitro models simple to implement (using human cell lines), to study effects of NPs on the ACB. In a first time, pro-inflammatory effects of SiO2 and TiO2 NPs were studied on co-cultures of alveolar epithelial cells (A549 and NCI-H441 cell lines), and macrophages (THP-1 cell line). We demonstrated the importance of cell cooperation during inflammatory processes caused by these NPs, and the role of the cellular ratio in these inflammatory responses. In a second time, effects of fluorescent polystyrene NPs on the ACB integrity, and their translocation were studied on three-dimensional co-cultures in bicameral chambers involving macrophages (THP-1 cell line), bronchial epithelial cells (Calu-3 cell line), and micro-vascular pulmonary endothelial cells (HPMEC ST1.6R cell line). The use of Calu-3 has provided a good barrier, but further investigations on microporous membranes are still needed to not interfere with NPs translocation. Altogether, these results show that a tailored approach should be considered in order to study toxicity or translocation of NPs

Abstract Minimum quantity lubrication (MQL) with nanocomposite particles is among the new areas of study and has proven to provide very good cooling and lubrication in the machining of difficult to cut materials, such as titanium, Inconel and ADI. It is therefore imperative to understand their effects on the environment in the early stages of investigation, prior to their wide scale usage in industry. This study focuses on the different nanocomposite particles used in previous research, which is available in the literature, and evaluates their sustainability characteristics by investigating the toxicity of these nanocomposite particles on humans. The cooling capabilities of each of the nanoparticles considered is first established from the existing literature and summarized. Human cell viability measured from in vitro toxicity studies of nanoparticles is used as a variable to easily capture the toxicity of nanoparticles. Six different human cell lines were chosen to represent the effects of possible exposure through inhalation [human lung epithelial cells (A549), and bronchial epithelial cells (NL-20)], ingestion (AGS, and HepG2) and dermal contact (THP-1, and human peripheral blood cells). A comparison table was developed (Table 2.0), which provides easy interpretation of the toxicity levels of the five nanoparticles that were considered using all three human cell lines. The drawback of this comparison is the lack of sufficient data to assign conclusive toxicity levels to the nanoparticles. The toxicity studies of nanoparticles on humans is still in its infancy and contradictory results exist for some of the nanoparticles. This is the first attempt to combine the results of the experimental investigations of nano-MQL cooling and the toxicity studies of nanoparticles, allowing researchers to make informed decisions in the selection of the most sustainable nanoparticles in the nano-MQL machining process.