Effect of sublethal concentration of antibiotics on the adherence of Staphylococcus epidermidis to eukaryotic cells.

Adherence of Staphylococcus epidermidis to pharyngeal epithelial cells as measured by [3H]-leucine-labelled bacteria was found to be a simple, objective and highly reproducible technique. Sublethal concentrations of cephalothin, rifampicin and vancomycin significantly reduced the bacterial adherence to epithelial cells, the effect being most marked with 1/2 MIC. Cloxacillin increased the adherence for one strain while it decreased it for the second. The effect was dose-related and the maximum reduction was observed when bacteria were grown with an antibiotic overnight.