Microbial and host factors that influence adherence of Escherichia coli to kidney epithelium

The adherence of Escherichia coli 06K13H1 to punch biopsy specimens of rabbit renal pelvic tissue and isolated epithelial cells was examined quantitatively. Organisms with pili adhered readily to kidney tissue, whereas organisms without pili (nonpiliated or grown in glucose-containing media) had significantly less adherence. Adherence was inhibited by antibody to pili antigen but not by mannose (a determinant of adherence to buccal mucosal cells). Studies were done to evaluate adherence under conditions operative in the renal medulla. The combination of hypertonic salt or urea solutions in acid pH interfered with adherence of the mannose-resistant strain. In additional studies of kidneys from humans, a similar effect of antipili serum and mannose was seen. These studies provide further evidence that pili are important in the initiation of upper urinary tract infection and define host factors that may inhibit initiation of infection.