Outer membrane protein P2 of nontypeable Haemophilus influenzae (OMP P2)

Outer membrane protein P2 (OMP P2) is the most abundant surface protein and the primary porin of nontypeable Haemophilus influenzae (NTHi), a major human respiratory pathogen (UniProt: P06120). It functions as a non-specific channel for the diffusion of small solutes across the bacterial outer membrane and plays a critical role in bacterial fitness and host cell adhesion (PubMed: 15210883). Because NTHi lacks a polysaccharide capsule, OMP P2 and other surface antigens are the primary targets for the host immune response and are central to vaccine development efforts (PubMed: 11514317). OMP P2 is highly immunogenic, but its external loops exhibit significant sequence variability among strains, allowing the bacteria to undergo antigenic variation and evade host immunity (PubMed: 25605281). This variability presents a significant challenge for the development of a universal vaccine, as antibodies generated against one strain may not protect against others. Current therapeutic strategies focus on identifying conserved regions within OMP P2 and other surface antigens to induce broadly protective bactericidal antibodies. These antigens are particularly relevant in the context of preventing otitis media in children and exacerbations of chronic obstructive pulmonary disease in adults.

Other names

Porin P2Major outer membrane protein P2OmpP2Nontypeable Haemophilus influenzae surface antigens

Induction of bactericidal and opsonizing antibodies through active immunization to prevent bacterial colonization and infection.