The role of pili in the adhesion of Escherichia coli to human urinary tract epithelial cells.

Pili or fimbriae were purified by a new technique involving solubilization from the bacterial outer membrane by deoxycholate and separation from flagella by 6M urea. This technique was employed to clarify the role of pili for the adherence of urinary tract pathogenic E. coli; a virulence factor in urinary tract infection. The isolated pili formed single bands in SDS gels and were pure by serologic criteria. They retained the binding properties of the whole piliated bacteria, since they bound to uroepithelial cells and agglutinated erythrocytes. Antibodies to purified pili blocked adhesion. The adhesion and hemagglutination reactions by the strains used for pilus purification were mannose-resistant but globotetraos-sensitive, i.e. the strains recognized globoseries glycolipid receptors in the target cells. The occurrence of this property in a freshly collected material of strains was tested using erythrocytes of blood groups P1, P2k and p.