Immunomodulation of cell-mediated cytotoxicity after chronic exposure to vapors.

Cytotoxic T lymphocytes and natural killer (NK) cells represent two major types of immune cytotoxic cells that have a crucial role in innate immunity. Urban air pollution represents a common and difficult problem in the majority of metropolises, which contain high levels of traffic congestion generating great amounts of genotoxic substances. Diesel exhaust particles act as adjuvant in the immune response and may lead to the enhancement of proinflammatory and proallergic response without exposure to allergen. The activities of diesel exhaust particles (DEPs) and their benzene extracts may cause the increasing respiratory mortality and morbidity. Since the lung inflammatory response to DEPs is compartmentalized, the importance of finding the suppressive substances, whose function will be to elucidate the DEPs effects, is fundamental. The objectives of this study were to examine the NK-mediated cytotoxicity against human NK-sensitive target, as well as the values of BTEX (benzene, toluene, ethylbenzene and xylene isomers) in urine in people from industrial area and those from rural fields. NK-mediated cytotoxicity of peripheral blood mononuclear cells was investigated against human NK-sensitive K-562 tumor cell line. BTEX were analyzed from urine by a HS-SPME method. All exposed individuals were demonstrated the significant decreased of NK-mediated cytotoxicity against human NK-sensitive target and increasing BTEX values. BTEX-analyze in urine and determination of NK-mediated cytotoxicity, as an important methods represent good markers in environmental monitoring, which contribute to the better protection of air pollutants and quicker diagnosis of environmental diseases.