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Quantitative Assessment of Human Neutrophil Migration Across a Cultured Bladder Epithelium
Published on: November 8, 2013
Interaction of bladder glycoprotein GP51 with uropathogenic bacteria
D E Shupp Byrne1, J F Sedor, M Soroush
1Department of Urology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
The Journal of Urology
|March 21, 2001
Summary
Glycoprotein GP51, a bladder mucin component, binds to and aggregates uropathogens, increasing significantly during urinary tract infections. This suggests GP51 plays a key role in the bladder's natural defense against bacterial invasion.
Area of Science:
- Urology
- Microbiology
- Immunology
Background:
- Bladder surface mucin contains glycoprotein GP51 (51 kD).
- GP51 has been isolated from rabbit mucosa and functions in an in vivo infection model.
- GP51 coats the epithelium and is secreted into urine, increasing during urinary tract infections (UTIs).
Purpose of the Study:
- To investigate the role of GP51 in the primary defense mechanism of the bladder.
- To study the interactions between GP51 and uropathogenic bacterial isolates.
- To analyze GP51 levels in urine from patients with symptomatic UTIs.
Main Methods:
- Enzyme-linked immunosorbent assay (ELISA) to assess GP51 binding to uropathogens.
- Immunochemical studies using monoclonal antibodies to GP51 to determine interactions with bacterial isolates (e.g., E. coli, S. aureus).
- Immunocytochemical testing of clinical specimens and bacterial cultures to localize GP51.
- Antigen inhibition ELISA to quantify urinary GP51 in normal controls and UTI patients.
Main Results:
- GP51 demonstrated semiquantitative binding to a broad range of gram-positive and gram-negative uropathogens.
- Immunochemical methods confirmed GP51 binds to, encapsulates, and aggregates bacteria.
- GP51 was localized to bacteria and uroepithelial cells in clinical specimens.
- A significant increase in urinary GP51 was observed in UTI patients compared to controls (p = 0.0003).
Conclusions:
- GP51, a bladder mucin component, exhibits direct antimicrobial properties.
- GP51 may serve as a crucial element in the bladder's innate immune defense system.
- Elevated urinary GP51 levels indicate its involvement in combating UTIs.
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