In single DE exposure studies, mice were pretreated with 0 or 1 ng MaR1 given i.p. at 18 hrs and 30 minutes prior to a single intranasal dose of DE. In repetitive DE exposure studies, mice were pretreated with 0 or 10 ng MaR1 given i.p. 30 minutes prior to an intranasal dose of DE, given daily for 15 consecutive weekdays. At five hours following final DE exposure, lungs were formalin-fixed and inflated for paraffin embedding and sectioning.
Immunohistochemistry was performed to assess ICAM-1 expression levels in airway epithelial cells following DE treatment with or without MaR1 pretreatment. Treatments: (A) single vehicle + saline, (B) single vehicle + DE, (C) single 1 ng 7(S)-MaR1 + DE, (D) repetitive vehicle + saline, (E) repetitive vehicle + DE, (F) repetitive 10 ng 7(S)-MaR1 + DE, (G) Secondary antibody only control. N ≥ 3 mouse lungs used in analyses per group. Arrows indicate representative points of staining (ICAM-1 expression).