Further characterization of the tracheal receptor for Pseudomonas aeruginosa

The purpose of this study was to obtain more information on the nature of the macromolecule to which Pseudomonas aeruginosa adheres. Acid-injured tracheal epithelium was treated with trypsin or lipase to determine whether the receptor molecule was a protein or a lipid. Lipase treatment significantly reduced adherence to these cells, whereas trypsin had no effect. Since the receptor appeared to be a lipid containing sialic acid, gangliosides were used to test whether they would inhibit adherence. Crude ganglioside preparations inhibited adherence in a dose-dependent manner when added to the bacteria before exposure to tracheal cells. Lastly, fibronectin, which presumably binds to gangliosides, significantly reduced the adherence of these organisms. According to these findings Pseudomonas aeruginosa appears to adhere to a sialic acid-containing glycolipid on cell surfaces, probably a ganglioside.