FIG. 3.

Inhibition of hemagglutination by purified PIA. Serial dilutions of the biofilm-producing, PIA-positive S. epidermidis 1457 and the isogenic biofilm-negative PIA-negative transductant 1457-M11 were applied to the wells of a microtiter plate. To each well purified PIA was added at a concentration of 9 μg/ml (PIA). Control wells did not contain PIA and contained only phosphate-buffered saline (PBS). The hemagglutination titers were assessed as described in Materials and Methods.