title: PiuA and PiaA, iron uptake lipoproteins of Streptococcus pneumoniae, elicit serotype independent antibody responses following human pneumococcal septicaemia.
abstract: Streptococcus pneumoniae causes considerable morbidity and mortality worldwide. The need for a cheap and effective pneumococcal vaccine has necessitated the evaluation of common virulence-associated proteins as potential vaccine antigens. PiuA and PiaA are the lipoprotein components of two pneumococcal iron ABC transporters. Here, we show that patients with culture confirmed pneumococcal septicaemia have elevated levels of antibody to PiuA and PiaA in convalescent-phase, compared with acute-phase serum. Additionally, sera from septicaemic patients infected with 13 pneumococcal strains covering eight different serotypes, cross-reacted with recombinant PiuA-His(6) and PiaA-His(6) from a single pneumococcal strain, indicating that this immune response is serotype independent. Anti-PiuA and anti-PiaA antibodies were also found in healthy seven-month-old infants, indicating that they are immunogenic at a very early age.
authors.affiliation: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK. rwhalan@nimr.mrc.ac.uk
authors.forename: Rachael H
authors.initials: RH
authors.lastname: Whalan
authors.forename: Simon G P
authors.initials: SG
authors.lastname: Funnell
authors.forename: Lucas D
authors.initials: LD
authors.lastname: Bowler
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Hudson
authors.forename: Andrew
authors.initials: A
authors.lastname: Robinson
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Dowson
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology*; D006801:Humans; D007223:Infant; D007501:Iron / Q000378:metabolism; D008074:Lipoproteins / Q000276:immunology*; D026901:Membrane Transport Proteins / Q000276:immunology; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000276:immunology* / Q000382:microbiology; D011994:Recombinant Proteins / Q000276:immunology; D018805:Sepsis / Q000276:immunology* / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000276:immunology*
chemical_list: D018528:ATP-Binding Cassette Transporters; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D008074:Lipoproteins; D026901:Membrane Transport Proteins; D011994:Recombinant Proteins; D007501:Iron