Localization of binding sites for purified Escherichia coli P fimbriae in the human kidney

Abstract

Binding sites in the human kidney for purified P fimbriae of pyelonephritogenic Eschenichia coli were determined. The purified KS71A (F71) fimbriae bound only to epithelial elements of the kidney, i.e., to the apical aspect of proximal and distal tubular cells, as well as to the apical and cytoplasmic sites of collecting ducts. In addition, binding was seen at the vascular endothelium throughout the kidney and at the parietal epithelium of the glomeruli. The binding was specifically inhibited by the receptor analog of E. coli P fimbriae, globotriose. The binding sites identified suggested a possible pathogenetic mechanism for the invasion of P-fimbriated bacteria into the renal parenchyma, as well as for their subsequent spread into the circulatory system. G (Dakopatts a/s, Glostrup, Denmark) diluted 1:40 in PBS. 328 on July 4, 2020 by guest http://iai.asm.org/ Downloaded from LITERATURE CITED 1. Brinton, C. C. 1965. The structure, function, synthesis and genetic control of bacterial pili and a molecular mechanism for DNA and RNA transport in Gram-negative bacteria.

UropathogenicEscherichia coliAL511 requires flagellum to enter renal collecting duct cells

“…Similarly, none of the bacterial mutants analysed displayed significantly lower than normal levels of internalization, suggesting that the mechanism of entry of AL511 into CD cells differs from that of the UPEC UTI89 and NU14 strains in bladder cells, in which type 1 adhesins have been shown to play a central role. P fimbriae, which are produced by most pyelonephritis isolates (Bergsten et al ., 2005) and recognize receptors located on the luminal surface of renal tubules (Korhonen et al ., 1986; Connell et al ., 2000), do not seem to be involved in the uptake of AL511 into renal epithelial cells. UPEC strains expressing Afa adhesins also display a unique renal tissue tropism (Nowicki et al ., 1988; Lalioui and Le Bouguénec, 2001; Le Bouguénec, 2005).…”

Binding of Escherichia coli S fimbriae to cultured human endothelial cells

“…Our results confirm the accessibility of specific binding sites for S fimbriae on living human endothelial cells. In contrast, the binding of P fimbriae to the cultured endothelial cells was unexpectedly low compared with their intense binding to vascular endothelium in kidney sections (10). This might be due to the inability of the immunohistochemical method to detect quantitative differences in the binding of different fimbriae, but it may also suggest that the binding sites observed in the immunohistochemical study are poorly accessible for P fimbriae on intact endothelial cells.…”

“…4). Earlier immunohistochemical studies employing incubation of purified adhesins with tissue sections have demonstrated intense binding of S fimbriae (8) and P fimbriae (10) to vascular endothelium in human kidney. In similar experiments, no binding of type 1 fimbriae to human vascular endothelium was observed (24).…”

Blood Groups in Infection and Host Susceptibility

“…P fimbria is a particularly important adhesin and is expressed by nearly 100% of strains associated with pyelonephritis (395). P-fimbriated E. coli is able to bind the uroepithelium as well as proximal renal tubules, glomerular epithelium, and vascular endothelium (396,397). P fimbriae not only facilitate multivalent bacterial adhesion to uroepithelium but also stimulate the release of inflammatory mediators through ceramide and Toll-like receptor (TLR4) pathways (394,398,399).…”