Helicobacter pylori cytotoxin: importance of native conformation for induction of neutralizing antibodies

• DOI: 10.1128/iai.63.11.4476-4480.1995
• Publication Date: 2020-01-06T18:43:53Z
• Authors: R Manetti; P Massari; D Burroni; M de Bernard; A Marchini; R Olivieri; E Papini; C Montecucco; R Rappuoli; J L Telford
• Keywords: Conformational epitope

We have attempted to express the Helicobacter pylori vacuolating cytotoxin in Escherichia coli. Although 95-kDa VacA polypeptide was expressed abundantly, it completely lacked any biological activity. In addition, this material failed induce neutralizing antibodies after immunization of rabbits. contrast, highly purified high-molecular-mass from supernatant H. cultures active a HeLa cell assay and effectively induced response Neutralizing sera were shown contain high proportion which recognized conformational epitopes found only on native toxin. The data indicate that toxin-neutralizing are potential vaccines based may benefit use intact molecule.