The role of Campylobacter jejuni cytolethal distending toxin in gastroenteritis: toxin detection, antibody production, and clinical outcome

Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey, UKMortensen NP, Schiellerup P, Boisen N, Klein BM, Locht H, Abuoun M, Newell D, Krogfelt KA. Therole of Campylobacter jejuni cytolethal distending toxin in gastroenteritis: toxin detection, antibodyproduction, and clinical outcome. APMIS 2011; 119: 626–34.The role of Campylobacter jejuni cytolethal distending toxin (CDT) on clinical outcome after gastro-enteritis was investigated. Clinical data, blood serum samples, and Campylobacter spp. isolated, fromeach of 30 patients were collected over a period of 6 months. The CDT encoding genes, cdtABC, char-acterized by PCR, revealed that all but one of the C. jejuni strains had the wild-type sequence. Sequenc-ing of cdtABC from this strain showed two major deletions. From all of the strains, CDT titers weredetermined, and toxin neutralizing antibodies were documented using an in vitro assay. Three of thethirty clinical isolates, including the one with the mutant cdtABC coding genes, did not have a detect-able CDT activity. Analyzing the relationship between CDT titer, serum neutralization of CDT, andthe clinical outcome showed that campylobacteriosis caused by CDT-negative strains was clinicallyindistinguishable from that of patients infected with an isolate that produced high levels of CDT. Theseresults suggest that CDT does not solely determine severity of infection and clinical outcome.Key words: Campylobacter jejuni; cytolethal distending toxin; antibody neutralization; antibody;gastroenteritis.Ninell P. Mortensen, Biological and Nanoscale Systems Group, Biosciences Division, Oak RidgeNational Laboratory, P.O. Box 2008, Building 1061, MS 6445, Oak Ridge, TN 37831-6445, USA.e-mail: mortensennp@ornl.gov