Surface expression of ICAM-1 on HBEC and CD11b on AM. Photomicrographs of primary cultured HBEC and human AM on coverslips. Immunocytochemistry was performed using mouse anti-human CD54 monoclonal antibody on HBEC and mouse anti-human CD11b monoclonal antibody on AM. In the absence of PM10 stimulation HBEC rarely expressed CD54 (A). After stimulation with 100 μg/ml of PM10 for 24 h the majority of cells stained positively (arrows, pink cells) for CD54 (B). Expression of surface CD11b on AM (C) was unaffected by 2 h stimulation with PM10 (D). The scale bars represent 20 μm.