No evidence of cross-reactivity of human antibodies to a 33-mer peptide of the alpha-gliadin component of gluten with Bordetella pertussis pertactin

A 33-mer peptide of the α-gliadin component of gluten was recently identified as primary initiator of the inflammatory response to gluten in coeliac disease (CD) patients. This proline–glutamine-rich peptide (PG-peptide) is highly homologous to internal sequence of pertactin, an immunogenic protein of Bordetella pertussis. Using enzyme immunoassays, we measured serum antibodies to pertactin and to PG-peptide in 167 Finnish subjects including pertussis vaccine recipients and pertussis patients, CD and non-CD patients and healthy individuals. We found no cross-reactivity between human antibodies to the two different components, suggesting that neither pertussis immunization nor disease contributes to the pathogenesis of CD.