Immunization against urinary tract infections

Over the last few years there has been increasing emphasis placed on the importance of the role of bacterial adhesion, both in the initial stage and the clinical manifestations of urinary infection. It has been clearly demonstrated that all urinary infections are accompanied by an immunity response usually related in degree to the severity of the infectious lesion. Moreover, various in vitro and in vivo studies have demonstrated that bacterial adhesion to uro-epithelial cells can be inhibited immunologically. A study was conducted to analyze and compare results of different immunization procedures, in an animal model (female rat), on in vivo inhibition of adhesion to bladder epithelium of various bacterial strains. The bacteria selected were E. coli (075) and E. coli (06) with respectively a mannose-resistant (MR) hemagglutinin (HA) and a Klebsiella pneumoniae. The three immunization procedures were: intravaginal instillation, oral doses completed by intraperitoneal injection and subcutaneous administration. The instilled or injected antigen was made up of a formalized bacterial suspension emulsified in Freund's incomplete adjuvant: only the orally administered antigen was composed of live bacteria. Quantitative in vivo test of bacterial adhesion was by radioactive labelling of bacteria instilled into the bladder. Of the three immunization routes, only vaginal instillation significantly inhibited bacterial adhesion to bladder mucosa whatever the HA type involved. Furthermore, although E. coli (075), which possesses an HAMR, adhered more than E. coli (06) to the bladder wall, a marked and comparable inhibition of its adhesion was noted after immunization by the homologous (E. coli (075)) as by the E. coli (06) strain.(ABSTRACT TRUNCATED AT 250 WORDS)