Neisseria meningitidis serogroup B factor H binding protein variant 1.1 (fHbp variant 1.1)

Neisseria meningitidis serogroup B factor H binding protein (fHbp) variant 1.1 is a surface-exposed lipoprotein that is critical for the survival of the bacterium within the human host (PubMed: 19129481). Its primary biological function is to bind human factor H, which is a key down-regulator of the alternative complement pathway, thereby protecting the bacteria from complement-mediated lysis and opsonophagocytosis (UniProt: Q9K0U9). This recruitment of factor H allows the pathogen to evade the host's innate immune response, facilitating invasive diseases such as meningitis and sepsis (PubMed: 23074170). As a major target for vaccine development, fHbp variant 1.1 is included as a recombinant antigen in vaccines like Trumenba and Bexsero (FDA: Trumenba Prescribing Information). These vaccines work by inducing high titers of serum bactericidal antibodies that specifically target fHbp. These antibodies not only trigger the classical complement pathway for bacterial destruction but also block the interaction between fHbp and human factor H, effectively stripping the bacteria of their immune-evasive shield (PubMed: 25603990).

Other names

fHbpGNA1870LP2086Genome-derived antigen 1870Lipoprotein 2086

Induction of serum bactericidal antibodies that facilitate complement-mediated lysis and block factor H binding to the bacterial surface (PubMed: 25603990).