Local immune responses to the Campylobacter flagellin in acute Campylobacter gastrointestinal infection.

Intestinal immunoglobulin A (IgA) anti-campylobacter flagellin antibodies were measured by an enzyme-linked immunosorbent assay in patients with and without campylobacter infections. The level of fecal IgA antiflagellin antibodies was significantly higher in patients than in controls, but only 12 of 29 patients (41.4%) with a campylobacter infection had detectable IgA antibodies against flagellin (optical density, greater than or equal to 0.100). Further testing of fecal IgA antibodies from 10 patients with homologous and heterologous purified flagellins showed strain specificity in 1 patient. Cross-reactivity of fecal IgA antibodies with heterologous flagellins did not correlate with the Lior serotype of the isolate.