Regulation of macrophage inflammatory protein-2 gene expression in response to 2,4-dinitrofluorobenzene in RAW 264.7 cells

Several skin sensitizers, like 2,4-dinitrofluorobenzene (DNFB), are known to provoke contact hypersensitivity responses after topical application. Here, we show that DNFB can upregulate macrophage inflammatory protein-2 (MIP-2) expression in RAW 264.7 cells via a mechanism that is largely dependent on mitogen-activated protein kinase (MAPK) signaling pathways. ELISA-based transcription factor activation assays and chromatin immunoprecipitation assays revealed that functional interaction between AP-1 and MIP-2 promoter element is necessary for MIP-2 gene expression by DNFB. Interestingly, topical application of DNFB to NC/Nga mice increased MIP-2 expression in dermis, suggesting that MIP-2 contributes to the leukocyte infiltration associated with atopic dermatitis. These results provide additional insight of the mechanism of contact hypersensitivity induced by contact sensitizers.