Tamm-Horsfall protein inhibits binding of S- and P-fimbriated Escherichia coli to human renal tubular epithelial cells.

Escherichia coli is the predominant pathogen in urinary tract infections. Fimbriae are one of the major virulence factors of these bacteria, since these protein appendices contribute towards bacterial adhesion to epithelial cells. In clinical E. coli isolates from urinary tract infections, P fimbriae are more frequently present than S fimbriae. However, these two types of fimbriae mediate adhesion to cultured tubular epithelial cells equally well. Tamm-Horsfall protein, which is the most abundant protein in normal human urine, inhibits hemagglutination by E. coli expressing S fimbriae, but does not interfere with hemagglutination by P-fimbriated E. coli. Therefore, it has been speculated that Tamm-Horsfall protein may serve as a clearance factor for S-fimbriated E. coli in human urine. In our experiments, adherence of purified S fimbriae and of S-fimbriated E. coli to tubular epithelial cells was inhibited by Tamm-Horsfall protein, but the protein also decreased binding of P-fimbriated E. coli to approximately the same degree. We found less adherence of both types of fimbriae to a Madin-Darby canine kidney cell line expressing soluble and membrane-bound Tamm-Horsfall protein as compared with the control cell line. In conclusion, our in vitro data suggest that urinary Tamm-Horsfall protein may serve as a clearance factor for E. coli expressing both S and P fimbriae. In the light of these findings, the low clinical relevance of S-fimbriated E. coli for urinary tract infections may be readily explained; however, the predominance of P fimbriae remains unresolved.

Leeker A ，Kreft B ，Sandmann J ，Bates J ，Wasenauer G ，Múller H ，Sack K ，Kumar S ... -  《experimental nephrology》

Asparaginase inhibition of adhesion of type 1-fimbriated and P-fimbriated Escherichia coli to epithelial cell receptors.

Wehner MR ，Koch SR ，Kindinger L ，Nelson N ，Cowan MM ... -  《APPLIED MICROBIOLOGY AND BIOTECHNOLOGY》

[The role of fimbriae of Escherichia coli in urinary tract infections].

The incidence of P-fimbriated E. coli from patients with pyelonephritis, cystitis and asymptomatic bacteriuria was 78.6%, 31.9% and 22.2%, respectively. Almost all of the P-fimbriated E. coli have also type-1 fimbriae. In the in vitro test, P-fimbriated E. coli attached to the uroepithelial cells in higher number than the type 1 fimbriated E. coli. The results of the adhesion inhibition test suggested that simultaneous presence of P-and type 1 fimbriae is the most significant virulence factor in urinary tract infections.

Ishikawa S 《-》

The effect of nitric oxide on adherence of P-fimbriated uropathogenic Escherichia coli to human renal epithelial cells.

Svensson L ，Säve S ，Persson K 《-》

Adherence of vero cytotoxin-producing Escherichia coli serotype O157:H7 to isolated epithelial cells and brush border membranes in vitro: role of type 1 fimbriae (pili) as a bacterial adhesin expressed by strain CL-49.

Durno C ，Soni R ，Sherman P 《Clinical and Investigative Medicine》