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Jet exhaust particles alter human dendritic cell maturation

Centre Interdisciplinaire de Nanoscience de Marseille CINaM CNRS UPR 3118, Université Aix-Marseille 2, Campus de Luminy, case 913, 13288 Marseille Cedex 9, France.
Agents and Actions (Impact Factor: 2.14). 10/2010; 60(3):255-63. DOI: 10.1007/s00011-010-0262-9
Source: PubMed

ABSTRACT Among combustion-derived air pollutants, little is known about jet kerosene characteristics and effects.
Particles yielded by experimental kerosene combustion in a jet engine were characterized with electron microscopy and X-ray energy dispersive spectroscopy. Immature human monocyte-derived dendritic cells were exposed for 18 h to 10, 25 or 100 μg/mL jet exhaust particles and/or Escherichia coli-derived endotoxin. Antigen-presenting and costimulation molecules (HLA DR, CD40, CD80, CD86, CD11c), tumor necrosis factor-α and interleukin-10 production were measured.
The primary particles of jet exhaust are spherical (9.9 nm), carbonaceous and exert an adjuvant effect on human monocyte-derived dendritic cell maturation in vitro. Concomitant particle and endotoxin stimulation induced a high cytokine production with low antigen-presenting molecules; particle contact prior to endotoxin contact led to an opposite phenotype. Finally, low cytokine production and high costimulation molecules were present when particle adjunction followed endotoxin contact.
Jet exhaust particles act as adjuvants to endotoxin-induced dendritic cell maturation, suggesting possible implications for human health and a role for the time pattern of infectious and pollutant interplay.

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