Immortalized human bladder cell line exhibits amiloride-sensitive sodium absorption

Area of Science:

• Urology
• Cell Biology
• Biotechnology

Background:

• Interstitial cystitis (IC) is a chronic bladder condition.
• Studying human bladder epithelial cells is crucial for understanding IC.
• Existing cell models have limitations in replicating in vivo conditions.

Purpose of the Study:

• To develop a continuous, immortalized human bladder epithelial cell line.
• To characterize the functional properties of the developed cell line.
• To provide a model for studying bladder physiology and pathophysiology.

Main Methods:

• Retroviral transduction of simian virus 40 (SV40) large T antigen into patient-derived urothelial cells.
• Culture of cells in hormonally supplemented medium with NIH-3T3 fibroblast coculture.
• Characterization of epithelial morphology, cytokeratin expression, and junctional complexes.
• Assessment of transepithelial electrical resistance and ion transport (Na+ absorption).

Main Results:

• Successfully produced a continuous, immortalized urothelial cell line.
• Cells exhibited epithelial morphology, cytokeratin positivity, and nuclear localization of SV40 T antigen.
• Formed a complex epithelium with tight junctions and stratification on permeable supports.
• Demonstrated high transepithelial resistance and active, amiloride-sensitive Na+ absorption, indicating functional Na-K-adenosinetriphosphatase.

Conclusions:

• The developed immortalized bladder cell line accurately models human urothelium.
• This cell line serves as a valuable tool for investigating bladder epithelial function.
• It facilitates research into the mechanisms of interstitial cystitis and responses to various stimuli.