Purification of the recombinantly produced Helicobacter pylori antigens NAP and FlaA

Abstract

Helicobacter pylori is a Gram-negative flagellated bacterium that infects the stomach of around 50 % of the worlds population, and can give rise to serious disease such as chronic gastritis, duodenal ulcer and stomach cancer. The current treatment against H. pylori, consisting of a combination of a proton pump inhibitor and two different antibiotics, is effective but has several drawbacks such as increased risk of antibiotic resistance and no protection against re-infection. Although extensive research is going on to develop a vaccine that would be an attractive alternative or complement to the current treatment, there is no vaccine available against H. pylori today. Antibodies to a number of antigens have been detected in the sera of infected patients, and many of these are known to be virulence factors, and are considered as candidate H. pylori vaccine antigens, alone or in a combination. Two such antigens are Neutrophil-activating protein (NAP) and Flagellin A (FlaA). In this project the H. pylori antigens NAP and FlaA were cloned and expressed in E. coli, and a purification strategy were set up for the two proteins.