Extracellular Release of Antigenic Proteins by Helicobacter pylori

Screening a Helicobacter pylori genomic library with antisera raised against H. pylori broth culture supernatant resulted in the identification of six antigens: urease, HspB, Lpp20, DnaK, MsrA, and a cysteine-rich 28-kDa protein (designated HcpA). H. pylori antigens may be released into the extracellular space by multiple mechanisms, including specific secretion pathways, autolysis, and membrane vesicle formation.