The relationship between adherence of Pseudomonas aeruginosa to upper respiratory cells in vitro and susceptibility to colonization in vivo.

The relationship between adherence of Pseudomonas aeruginosa to buccal cells in vitro and susceptibility of the oropharynx to colonization by P. aeruginosa in vivo was examined in rats subjected to food and water deprivation. After food and water deprivation for 3 days, buccal cell adherence of P. aeruginosa was significantly greater than the control group values, and all treatment animals inoculated intraorally with P. aeruginosa at that time became colonized. These changes in cellular adherence in vitro and susceptibility to colonization persisted through the fourth day of deprivation and the first day of refeeding, and no treatment animals inoculated with P. aeruginosa at that time became colonized. Following renal infarction, buccal cell adherence of P. aeruginosa was increased within 24 hr; the magnitude and duration of this increase were related to the extent of renal infarction. Nearly all animals (34 of 36) inoculated intraorally with P. aeruginosa at a time when their buccal cell adherence values in vitro were increased above control values became colonized with the organism. These data suggest a strong relationship between epithelial cell binding of gram-negative bacilli in vitro and susceptibility to colonization with these organisms. The mechanisms by which respiratory epithelial cell adherence of P. aeruginosa is increased remain speculative.