The effects of benzene and toluene on leukotactin-1-induced migration of EoL-1 cells

Benzene and toluene are volatile organic compounds (VOCs) that are produced from various building materials and may lead to sick building syndrome. In addition, these materials exert cytotoxic and carcinogenic effects in immune cells. To understand the effects of VOCs on immunological regulation, we investigated the effects of VOCs on cell migration in response to CC chemokines such as leukotactin-1 (Lkn-1), monocyte chemoattractant protein-1 (MCP-1), eotaxin, MIP-1α and RANTES in human eosinophilic leukemia EoL-1 cells. VOCs exerted no cytotoxicity against EoL-1 cells at concentrations ranging from 0.1 μM to 50 μM. A chemotaxis assay was conducted to evaluate the cell movement. The assay revealed that benzene and toluene differentially increased the migration of EoL-1 cells in response to Lkn-1, but not MCP-1, eotaxin, MIP-1α or RANTES. The expression of CCR1 and CCR3 binding to Lkn-1 were not altered by benzene and toluene. Additionally, the increased cell migration due to benzene and toluene was inhibited by PD98059, SB202190 and SP600125. Benzene and toluene also induced the phosphorylation of ERK, p38 mitogen-activated protein kinase (p38 MAPK) and JNK in a time-dependent manner. Overall, benzene and toluene influenced Lkn-1-induced migration of human eosinophilic cells via activation of MAPKs. These results suggest that benzene and toluene play a role as risk factors in the regulation of immune response. Furthermore, these findings provide a role for VOCs in the immunological processes involved in indoor air pollution-induced diseases.