Antibody coating of bacteria in experimental infection of the urinary bladder.

We studied antibody coating of urinary bacteria in experimental cystitis of the rat both in the absence and presence of a foreign body (polyacrylamide sphere). In the absence of a foreign body, inoculation of the bladder urine resulted in generally transient bacteriuria with no significant antibody coating or defects in the bladder uroepithelium, lymphocytic infiltration of bladder mucosa, or plasma cells in the bladder mucosa. Inoculation in the presence of a foreign body resulted in protracted bacteriuria with significant antibody coating of urinary bacteria, defects in the bladder mucosa surface, lymphocytic infiltration of the bladder mucosa, and numerous plasma cells. We conclude that the bladder mucosa is capable of mounting a local immune response against bacterial invasion which leads to antibody coating of urinary bacteria.