Study On The Immunogenicity Of Helicobacter Pylori UreI And The Therapeutic Effect As Its DNA Vaccine

Objective:Helicobacter pylori (Hp) is a human gastric pathogen that survives under the strong acidity of the stomach by virtue of its urease activity. This activity produces ammonia, which could neutralize gastric acid and provides the bacterial parasite microenvironment. UreI, one main open reading frams (ORF) of urease and an membrane protein, was found to be of important role against this low pH, espcially for the gastric colonization of Helicobacter pylori. Rereaches had indicated UreI behaves like an H~+-gate for urea channel, and displayed very rapid stimulation of extracellular ammonia production upon exposure to pH≤5. This response was specific for urea hydrolysis. In this study, we hope to explore the immunogenicity of UreI and the possibility of its DNA vaccine against Hp infection after the DNA inserted into expressing vector.Mehods and results:We cloned the ureI gene from helicobacter pylori by PCR and constructed the procaryotic expression plasmid, pET32a(+)-ureI.