The role of Tamm-horsfall glycoprotein in controlling the incidence of urinary tract infections in catheterized geriatric patients

Abstract

Cranberry juice cocktail (CJC) has been shown by numerous researchers to be a powerful inhibitor of bacterial adherence to uroepithelial cells in vitro and in vivo. In a previous study performed in this laboratory, a significant increase in antiadherence activity was seen in the urine of nursing home patients after ingestion of the cocktail. In the current study, Tamm-Horsfall glycoprotein (THP) was extracted from these urine samples and examined for antiadherence activity. A significant increase in antiadherence activity was observe in five of the eight samples. To date, neither CJC, or any of its metabolic breakdown products have been found associated with the increase in antiadherence activity that occurs after ingestion of the cocktail. This study suggests that the observed increase in antiadherence activity of the urine is due to Tamm-Horsfall glycoprotein, which is produced in the ascending loop of Henle in the kidney and secreted into the urine. Using SDS-PAGE and UV absorbance, it appears that the increased antiadherence activity of the urine is not associated with an increase in the quantity of THP but rather a qualitative change in the molecule. It is suggested that this qualitative change in THP may be due to the unfolding of the glycoprotein, exposing additional binding sites to interact with the invading bacteria.