Role of type 1 fimbria- and P fimbria-specific adherence in colonization of the neurogenic human bladder by Escherichia coli

Recent clinical studies suggest that the deliberate colonization of the human bladder with a prototypic asymptomatic bacteriuria-associated bacterium, Escherichia coli 83972, may reduce the frequency of urinary tract infection in individuals with spinal cord injuries. However, the mechanism by which E. coli 83972 colonizes the bladder is unknown. We examined the role in bladder colonization of the E. coli 83972 genes papG and fimH, which respectively encode P and type 1 receptor-specific fimbrial adhesins. E. coli 83972 and isogenic papGDelta and papGDelta fimHDelta mutants of E. coli 83972 were compared for their capacities to colonize the neurogenic human bladder. Both strains were capable of stable colonization of the bladder. The results indicated that type 1 class-specific adherence and P class-specific adherence, while implicated as significant colonization factors in experiments that employed various animal model systems, were not required for colonization of the neurogenic bladder in human beings. The implications of these results with regard to the selection of potential vaccine antigens for the prevention of urinary tract infection are discussed.