Adhesion of mucoid uropathogenic strains of Pseudomonas aeruginosa to HEp-2 cells.

We studied a pili-independent adhesion mechanism to HEp-2 cells present in mucoid uropathogenic strains of Pseudomonas aeruginosa. Our data demonstrate that bacterial adhesion to HEp-2 cell surfaces is time dependent and that the phenotypes involved are influenced by bacterial growth conditions. Sonicated bacterial extracts competitively inhibit the adherence of homologous strains to HEp-2 cells. Adhesins that are heat and trypsin sensitive are located on the surface of the bacterial outer membrane. Immunogenic 55 kDa surface protein is required for the adherence to HEp-2 cell surfaces of non-piliated mucosal uropathogenic P. aeruginosa strains.