Outer inflammatory protein A (OipA) (OipA)

Outer inflammatory protein A (OipA) is a significant outer membrane protein and virulence factor of the gastric pathogen Helicobacter pylori (Yamaoka et al., 2000, PubMed: 10948120). It functions primarily as an adhesin, playing a critical role in the attachment of the bacterium to the gastric mucosa, which is essential for persistent infection and colonization (Dossumbekova et al., 2006, PubMed: 16912302). In addition to its adhesive properties, OipA acts as a potent pro-inflammatory stimulus, triggering the production of interleukin-8 (IL-8) in gastric epithelial cells via the activation of the NF-κB and MAPK signaling cascades (Yamaoka et al., 2004, PubMed: 15258109). The expression of OipA is regulated by a phase-variation mechanism involving slipped-strand mispairing in the 5' region of the hopH gene, resulting in functional "on" or "off" states (Teymournejad et al., 2017, PubMed: 28414018). Strains with the OipA "on" status are strongly associated with higher bacterial loads, increased gastric inflammation, and a significantly elevated risk of developing duodenal ulcers and gastric adenocarcinoma (Kudo et al., 2004, PubMed: 15557550). Due to its surface exposure and central role in H. pylori pathogenesis, OipA is a prominent target for the development of vaccines and novel antimicrobial agents designed to block bacterial adhesion (Liu et al., 2020, PubMed: 32153485).

Other names

HopHOuter membrane protein 13OMP13Helicobacter pylori adhesin OipA

OipA facilitates Helicobacter pylori adhesion to gastric epithelial cells and triggers pro-inflammatory signaling cascades, including the NF-κB and MAPK pathways, leading to the production of interleukin-8 (IL-8) (Yamaoka et al., 2004, PubMed: 15258109; Dossumbekova et al., 2006, PubMed: 16912302).