Hormone Modulation of Toll-Like Receptor 5 in Cultured Human Bladder Epithelial Cells

Area of Science:

• Urology
• Immunology
• Endocrinology

Background:

• The role of hormone levels in modulating Toll-like receptor 5 (TLR5) activity within the bladder remains largely unexplored.
• Toll-like receptor 5 is crucial for innate immunity, recognizing bacterial flagellin and initiating inflammatory responses.

Purpose of the Study:

• To investigate the impact of estradiol and progesterone on TLR5 expression and function in human bladder epithelial cells.
• To elucidate the relationship between hormone exposure and TLR5-mediated cytokine production.

Main Methods:

• Human urinary bladder (HUB) cells (T24) were cultured and exposed to estradiol, progesterone, or a combination, alongside hormone-free conditions.
• TLR5 expression and cytokine release (IL-6, MCP-1) post-flagellin stimulation were quantified using ELISAs.
• A TLR5 antagonist confirmed the specificity of flagellin-induced signaling.

Main Results:

• Both estradiol and progesterone suppressed TLR5 expression in HUB cells compared to hormone-free conditions.
• Hormonal environments differentially affected TLR5 functional activity, measured by IL-6 production.
• Progesterone exposure resulted in the highest IL-6 levels, while higher TLR5 expression correlated with reduced IL-6 release.

Conclusions:

• Hormone levels significantly modulate TLR5 expression and function in the bladder.
• Altered TLR5 activity may influence the susceptibility and severity of urinary tract infections.
• Understanding these hormonal effects is critical for managing bladder inflammation and infections.