Application of a liposomal subunit vaccine in chickens for reduction of Campylobacter gut colonisation.

Introduction: Campylobacter are the most common cause of food poisoning, which manifests itself in diarrhoea of varying severity. Additionally, because of the increasing number of people with immune deficiencies, more frequent serious complications of Campylobacter infections are being observed. The main source of infection is the consumption of contaminated poultry meat, which is a consequence of the insufficiency of current hygiene and biosecurity to control Campylobacter or eliminate it from the poultry food chain.

Material and methods: Two hybrid proteins, presenting selected epitopes of the Campylobacter antigens CjaD and EF-Tu, were developed based on the highly immunogenic proteins CjaA and CjaC. Four groups of chickens were vaccinated with different preparations (a mixture of both hybrid proteins encapsulated in anionic or neutral liposomes) and different doses (a single dose given on the day of hatching or two doses given on days 1 and 14 of life). The number of Campylobacter was assessed in the intestinal contents of vaccinated birds.

Results: No statistically significant differences in colonisation levels were observed between chickens immunised with neutral liposomes containing hybrid proteins and their non-immunised counterparts, regardless of dosage regimen.

Conclusion: Although immunisation of chickens did not produce the expected results, the approach used has great potential, which is worth further investigation and development.