title: Induction of antibodies by Staphylococcus aureus nasal colonization in young children.
abstract: In order to develop novel antistaphylococcal strategies, understanding the determinants of carriage and how humans respond to Staphylococcus aureus exposure is essential. Here, the primary S. aureus-specific humoral immune response and its association with nasal colonization was studied in young children. Sera from 57 colonized or non-colonized children, serially collected at birth and at 6, 14 and 24 months, were analysed for IgG, IgA and IgM binding to 19 staphylococcal proteins, using flow cytometry-based technology. The antibody responses showed extensive inter-individual variability. On average, the levels of antistaphylococcal IgA and IgM increased from birth until the age of 2 years (p <0.05), whereas the levels of IgG decreased (p <0.001). Placentally transferred maternal IgG did not protect against colonization. In colonized children, IgG and IgA levels for a number of proteins were higher than in non-colonized children. At both 14 and 24 months, the levels of IgG against chemotaxis inhibitory protein of S. aureus (at 24 months; median fluorescence intensity, 4928 vs. 24, p <0.05), extracellular fibrinogen-binding protein (987 vs. 604, p <0.05), and iron-responsive surface determinant H (62 vs. 5, p <0.05) were significantly higher in colonized children. The levels of IgA against CHIPS, IsdH and IsdA were higher (p <0.05). Therefore, CHIPS, Efb, IsdA and IsdH seem to play a role in nasal colonization of young children.
authors.affiliation: Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands. n.j.verkaik@erasmusmc.nl
authors.forename: N J
authors.initials: NJ
authors.lastname: Verkaik
authors.forename: A
authors.initials: A
authors.lastname: Lebon
authors.forename: C P
authors.initials: CP
authors.lastname: de Vogel
authors.forename: H
authors.initials: H
authors.lastname: Hooijkaas
authors.forename: H A
authors.initials: HA
authors.lastname: Verbrugh
authors.forename: V W V
authors.initials: VW
authors.lastname: Jaddoe
authors.forename: A
authors.initials: A
authors.lastname: Hofman
authors.forename: H A
authors.initials: HA
authors.lastname: Moll
authors.forename: A
authors.initials: A
authors.lastname: van Belkum
authors.forename: W J B
authors.initials: WJ
authors.lastname: van Wamel
mesh_terms: D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology; D002353:Carrier State / Q000276:immunology* / Q000382:microbiology; D002675:Child, Preschool; D003169:Complement Inactivator Proteins / Q000276:immunology; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D009297:Nasal Mucosa / Q000382:microbiology*; D011956:Receptors, Cell Surface / Q000276:immunology; D013203:Staphylococcal Infections / Q000276:immunology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000276:immunology* / Q000302:isolation & purification
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D003169:Complement Inactivator Proteins; C524396:Ehp protein, Staphylococcus aureus; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C512791:IsdA protein, Staphylococcus aureus; C512792:IsdH protein, Staphylococcus aureus; D011956:Receptors, Cell Surface; C493134:chemotaxis inhibitory protein, Staphylococcus aureus