Impact of tire debris on in vitro and in vivo systems

BACKGROUND: It is estimated that over 80% of respirable particulate matter (PM(10)) in cities comes from road transport and that tire and brake wear are responsible for the 3–7% emission of it. Data on the indicators of environmental impact of tire debris (TD), originated from the tire abrasion on roads, are extremely scarce, even though TD contains chemicals (zinc and organic compounds) which can be released in the environment. METHODS: TD particle morphology was analysed with SEM, TEM and FIB instruments. TD eluates and TD organic extracts were tested at dilution series on human cell lines and Xenopus laevis embryos. 50 and 100 g/L TD were used for the eluates obtained after 24 h at pH 3 and the quantity of zinc present was measured with a ICP-AES. Eluates diluted to 1%, 10%, 50% in culture media and undiluted were used on X. laevis embryos in the FETAX test. HepG2 cells were exposed for 24 h to 0.05 – 50 μg/ml of zinc salt while A549 cells were exposed for 24, 48 and 72 h to 10, 50, 60, or 75 μg/ml of TD extract. X. laevis embryos were exposed to 50, 80, 100, or 120 μg/ml TD extract. RESULTS: The solution of undiluted 50 g/L TD produced 80.2% mortality (p < 0.01) in X. laevis embryos and this toxic effect was three times greater than that produced by 100 g/L TD. Zn accumulation in HepG2 cells was evident after 4 h exposure. A549 cells exposed to TD organic extract for 72 h presented a modified morphology, a decrease in cell proliferation and an increase in DNA damage as shown by comet assay. The dose 80 μg/ml of TD extract produced 14.6% mortality in X. laevis embryos and 15.9% mortality at 120 μg/ml. Treatment with 80, 100, or 120 μg/ml TD organic extract increased from 14.8% to 37.8% malformed larvae percentages compared to 5.6% in the control. CONCLUSION: Since the amount of Zn leached from TD is related to pH, aggregation of particles and elution process, the quantity of TD present in the environment has to be taken into account. Moreover the atmospheric conditions, which may deeply influence the particle properties, have to be considered. The TD organic fraction was toxic for cells and organisms. Thus, because of its chemical components, TD may have a potential environmental impact and has to be further investigated

Toxic effects of brake wear particles on epithelial lung cells in vitro

Background: Fine particulate matter originating from traffic correlates with increased morbidity and mortality. An important source of traffic particles is brake wear of cars which contributes up to 20% of the total traffic emissions. The aim of this study was to evaluate potential toxicological effects of human epithelial lung cells exposed to freshly generated brake wear particles. Results: An exposure box was mounted around a car's braking system. Lung cells cultured at the air-liquid interface were then exposed to particles emitted from two typical braking behaviours ("full stop" and "normal deceleration"). The particle size distribution as well as the brake emission components like metals and carbons was measured on-line, and the particles deposited on grids for transmission electron microscopy were counted. The tight junction arrangement was observed by laser scanning microscopy. Cellular responses were assessed by measurement of lactate dehydrogenase (cytotoxicity), by investigating the production of reactive oxidative species and the release of the pro-inflammatory mediator interleukin-8. The tight junction protein occludin density decreased significantly (p &lt; 0.05) with increasing concentrations of metals on the particles (iron, copper and manganese, which were all strongly correlated with each other). Occludin was also negatively correlated with the intensity of reactive oxidative species. The concentrations of interleukin-8 were significantly correlated with increasing organic carbon concentrations. No correlation was observed between occludin and interleukin-8, nor between reactive oxidative species and interleukin-8. Conclusion: These findings suggest that the metals on brake wear particles damage tight junctions with a mechanism involving oxidative stress. Brake wear particles also increase pro-inflammatory responses. However, this might be due to another mechanism than via oxidative stress. [Authors]]]> Vehicle Emissions ; Particulate Matter ; Particle Size ; Epithelial Cells ; Toxicity Tests eng https://serval.unil.ch/resource/serval:BIB_834D29655A82.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_834D29655A828 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_834D29655A828 info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_834DC6847A73 2022-02-19T02:25:16Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_834DC6847A73 A liposomal peptide vaccine inducing CD8+ T cells in HLA-A2.1 transgenic mice, which recognise human cells encoding hepatitis C virus (HCV) proteins info:doi:10.1016/j.vaccine.2004.05.009 info:eu-repo/semantics/altIdentifier/doi/10.1016/j.vaccine.2004.05.009 info:eu-repo/semantics/altIdentifier/pmid/15519708 Engler, O. B. Schwendener, R. A. Dai, W. J. Wolk, B. Pichler, W. Moradpour, D. Brunner, T. Cerny, A. info:eu-repo/semantics/article article 2004-11 Vaccine, vol. 23, no. 1, pp. 58-68 info:eu-repo/semantics/altIdentifier/pissn/0264-410X <![CDATA[Virus specific T cell responses play an important role in resolving acute hepatitis C virus (HCV) infections. Using the HLA-A2.1 transgenic mouse model we investigated the potential of a liposomal peptide vaccine to prime a CD8(+) T cell response against 10 different HCV epitopes, relevant for human applications. We were able to demonstrate the induction of strong cytotoxic T cell responses and high numbers of IFN-gamma-secreting cells, which persisted at high levels for at least 3 months. Co-integrating CpG oligonucleotides into liposomes further increased the number of IFN-gamma-secreting cells by 2-10-fold for most epitopes tested. The frequency of specific cells was further analysed with chimeric A2 tetramers bearing the NS31073-1081 epitope and was estimated at 2-23% of the CD8(+) T cell population. Importantly, mouse effector cells, specific for this epitope, were also capable of lysing a human target cell line expressing HCV proteins. This finding and the specific protection observed in challenge experiments with recombinant vaccinia virus expressing HCV sequences emphasise the biological relevance of the vaccine-induced immune response. In conclusion, such liposome formulations represent a safe and promising strategy to stimulate the CD8(+) T cell against HCV

Soluble iron modulates iron oxide particle-induced inflammatory responses via prostaglandin E2 synthesis: In vitro and in vivo studies

© 2009 Beck-Speier et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens