FIG. 7.

Inhibition of BC7 binding to NHBE cells by BEC CS fraction, mixed epidermal cytokeratins, and polyclonal antibody to mixed epidermal cytokeratins. FITC-labeled BC7 (10⁷ CFU/ml) were incubated with NHBE cells for 1 h and washed, and bound bacteria were detected by confocal microscopy. (a) No inhibitor added. (b to d) Preincubation of bacteria with keratin solubilization buffer (control) (b), buffer plus mixed epidermal cytokeratins (20 μg/ml) (c), and buffer plus BEC CS fraction (containing approximately 8.3 μg of CK13 per ml) (d). (e to h) Preincubation of cells with nonimmune serum control (e), antiserum to mixed epidermal cytokeratins (f), nonimmune serum preadsorbed on BEC CS fraction (g), and antibody to mixed epidermal cytokeratins preabsorbed on BEC CS fraction (h). Magnification bar, 10 μm.