It has been established that the urothelial mucin layer functions as a bacterial 
anti-adherence factor. Intravesical Bacillus Calmette-Guerin is used to treat 
patients with superficial bladder cancer. The proposed mechanism of action of 
Bacillus Calmette-Guerin is adherence to the urothelium with induction of an 
immunologic and/or inflammatory response. The current study was designed to 
determine if rabbit bladder mucin removal results in increased Bacillus 
Calmette-Guerin urothelial adherence. PAS and colloidal iron stains were used to 
demonstrate that intravesical instillation of 50% acetone renders rabbit bladder 
urothelium mucin deficient. The urothelium remains mucin deficient at two hours, 
but by 24 hours the mucin layer has been regenerated. Two hours following 
intravesical 3H-labeled Escherichia coli administration, bacterial adherence was 
29-fold greater in mucin deficient than mucin intact rabbits (p = 0.05). By 12 
hours, the difference in adherence was not significant. Two hours following 
intravesical administration of 3H-labeled Bacillus Calmette Guerin, mucosal 
adherence was 21-fold greater in mucin deficient compared to mucin intact 
rabbits (p = 0.002). After mucin removal, Bacillus Calmette Guerin urothelial 
adherence was significantly increased. The significant increase in Bacillus 
Calmette Guerin adherence after mucin removal may be clinically exploitable.