[Diesel particles and allergy: cellular mechanisms].

Urbain air pollutants, particularly diesel exhaust particles are now known to contribute to the increased prevalence of asthma and allergic rhinitis. Diesel exhaust particles act as adjuvants in the immune response and may lead to the enhancement of allergic inflammation. This was first suggested by epidemiological studies and now largely confirmed by numerous experimental studies in animals and humans. We review the different mechanisms involved, including effects on cytokine and chemokine production, as well as activation of different immune cells. We also discuss the metabolic and cellular activation pathways used by polycyclic aromatic hydrocarbons, allergens and their interaction with diesel particles which act in synergy in this immune response toward IgE production and induction of allergic inflammation.