Density and localization of P-fimbriae-specific receptors on mammalian cells: fluorescence-activated cell analysis
Insights
P-fimbriated Escherichia coli cause most childhood pyelonephritis. New methods using fluorescein-labelled bacteria and FACS analysis can quantify P-fimbriae receptors on cells, aiding infection studies.
Area of Science:
- Microbiology
- Immunology
- Cell Biology
Background:
- P-fimbriated Escherichia coli are the primary cause of acute non-obstructive pyelonephritis in children.
- Increased binding of P-fimbriated E. coli to uroepithelial cells in individuals prone to urinary tract infections suggests a host factor.
- High density of P-fimbriae receptors on urinary tract and kidney cells may predispose individuals to upper urinary tract infections.
Purpose of the Study:
- To develop and describe methods for determining the densities and localization of P-fimbriae receptors on mammalian cells.
- To investigate the role of P-fimbriae receptor density as a host factor in urinary tract infections.
Main Methods:
- Incubation of cells in suspension with fluorescein-labelled P-fimbriated E. coli.
- Analysis of cell suspension using fluorescence-activated cell sorting (FACS) to measure receptor density.
- Utilizing fluorescein-labelled P-fimbriated E. coli for receptor localization within tissues.
Main Results:
- Fluorescence-activated cell sorting (FACS) provides a versatile method for rapid and specific analysis of P-fimbriae receptor densities on large cell populations.
- Fluorescein-labelled P-fimbriated E. coli effectively localize P-fimbriae receptors in tissue samples.
- The developed techniques allow for quantitative assessment of receptor density and spatial distribution.
Conclusions:
- The described methods enable precise quantification and localization of P-fimbriae receptors on mammalian cells and tissues.
- These techniques are valuable for studying host-pathogen interactions, particularly in urinary tract infections caused by P-fimbriated E. coli.
- The methodology can be extended to investigate interactions between various microorganisms and their host cells.
Abstract:
More than 95% of acute non-obstructive pyelonephritis cases in children are caused by P-fimbriated Escherichia coli. Uroepithelial cells from individuals prone to urinary tract infections bind such bacteria more avidly than do cells from healthy controls. A high density of receptors for P-fimbriae on cells of the urinary tract and kidney may thus be an important host factor in the acquisition of upper urinary tract infections. In this communication we are describing methods to determine the densities and localization of P-fimbriae receptors on mammalian cells. To determine the receptor density on cells in suspension, the cells were incubated with fluorescein-labelled P-fimbriated E. coli. They were then subjected to fluorescence-activated cell sorting (FACS) analysis which monitors both the size and the relative fluorescence of each cell. FACS analysis proved versatile for rapid and specific analyses of P-fimbriae receptor densities on large numbers of any chosen type of cell. The fluorescein-labelled P-fimbriated E. coli were also useful in localizing P-fimbriae receptors in tissues. These techniques are not limited to the assessment of P-fimbriae receptor densities and tissue localization but open up new aspects for studies of the specificities involved in the interactions between other microorganisms (e. g. parasites, bacteria and virus) and their host cells.
