Campylobacter pylori virulence factors in gnotobiotic piglets.

Thirty-three gnotobiotic piglets from four litters were challenged with motile and nonmotile strains of Campylobacter pylori. The most motile strain, 26695, was the most virulent, with a 100% infection rate. The least motile strain, Tx30a, was the least virulent, with an infection rate of only 17%. Strain 60190 was weakly motile and had intermediate virulence, with an infection rate of 40%. Strains recovered from piglets were more motile than the challenge strains. The challenge strains also differed in cytotoxin production. The least virulent strain, Tx30a, was nontoxigenic, while the other two strains produced high levels of cytotoxin. Thus, virulence of C. pylori for gnotobiotic piglets correlated very well with motility and not as well with cytotoxin production.