Relationship between antibody to cytotoxin and Helicobacter pylori infection

Broth culture supernatants from 14 (34%) out of the 41 H. pylori strains tested, induced vacuolization in Intestine 407 cells in titers ranging from 1:2 to 1:64. 20% of H. pylori strains isolated from children and 42% of strains isolated from adults expressed vacuolating activity. Serum antibody to cytotoxin produced by H. pylori was detected with a neutralization assay. Anticytotoxic antibodies were present in all sera from patients infected with cytotoxic H. pylori strains. The toxin-neutralizing activity of sera from individuals infected with H. pylori suggests that the cytotoxin is produced in vivo.