Protein D from Non-typeable Haemophilus influenzae (Protein D)

Protein D from non-typeable Haemophilus influenzae is an outer membrane lipoprotein essential for bacterial virulence, possessing enzymatic activity that contributes to pathogenesis. Its high conservation across strains, strong immunogenicity, structural characterization, and proven efficacy as both an antigenic target and carrier molecule make it central to modern strategies combating respiratory tract infections through vaccination—most notably via its inclusion in multivalent pediatric vaccines like Synflorix™.

Other names

NTHi Protein DHaemophilus influenzae Protein DHiPDGlycerophosphodiester phosphodiesterase (GDPD)

Serves as a carrier protein in conjugate vaccines, enhancing the immune response to polysaccharide antigens. Enzymatic activity releases phosphorylcholine, contributing to pathogenesis.