Differential chemokine induction by 1-nitropyrene and 1-aminopyrene in bronchial epithelial cells: Importance of the TACE/TGF-α/EGFR-pathway

1-nitropyrene (1-NP), a common PAH in diesel exhaust, and its amine metabolite 1-aminopyrene (1-AP) induce distinctly different chemokine-responses in bronchial epithelial cells (BEAS-2B) characterized by increases in CXCL8 and CCL5, respectively. Tumor necrosis factor-α converting enzyme (TACE), which cleaves membrane-bound transforming growth factor (TGF)-α, activating the epidermal growth factor receptor (EGFR), may regulate pro-inflammatory responses induced by a variety of endogenous and exogenous agents. The present results suggest that CXCL8, but not CCL5 responses in 1-NP- or 1-AP-exposed cells required TACE/TGF-α/EGFR-signaling. The findings strengthen the notion that TACE/TGF-α/EGFR-signaling is central in epithelial CXCL8-regulation upon exposure to multiple airborne pollutants.

► NP induced a strong CXCL8-response but not CCL5 in BEAS-2B cells.
► AP induced a moderate increase in both CXCL8 and CCL5 in BEAS-2B cells.
► TACE/TGF-α/EGFR-signaling was crucial to induction of CXCL8, but not CCL5.
► EGFR may also have a TACE/TGF-α -independent role in regulation of both chemokines.
► TACE and EGFR may be central regulators of inflammation by multiple air pollutants.