title: Expression of idiotypic antibodies-1 and -2 and breastfeeding in relation to antibody levels against Haemophilus influenzae type B in children.
abstract: The aim of the study was to determine the concentrations of serum antibodies against Haemophilus influenzae type b in preschool children in relation to the distribution of idiotypic antibodies 1 and 2 (Id-1 and Id-2) and the exposure to breastfeeding in infancy. Sera were obtained from 74 control children recruited in an earlier case-control study before the introduction of general Hib vaccination. Duration of breastfeeding was monitored, and prevalence of noninvasive infections was registered. Concentrations of IgG1 and IgG2 anti-Hib, as well as of total Id-1 and Id-2, were determined in ELISA. The expression of Id-1 antibodies increased with age in contrast to the Id-2 antibodies that were found only in children up to 24 months of age. Expression of Id-1 antibodies was positively correlated with higher anti-Hib levels of both the IgG1 and IgG2 isotype. Children expressing Id-2 antibodies showed higher IgG2 anti-Hib concentrations than those who did not have Id-2 (P = 0.001). The concentrations of neither Id-1 nor Id-2 antibodies were related to the duration of breastfeeding. Duration of breastfeeding was related to increased anti-Hib IgG2 in healthy children above 18 months of age. These study shows that the expression of idiotype-1 and idiotype-2 antibodies was associated with higher IgG2 anti-Hib concentration and that breastfeeding could enhance the anti-Hib IgG2 production in children.
authors.affiliation: Department of Paediatrics, Orebro University Hospital, Orebro, Sweden. sven-arne.sifverdal@orebroll.se
authors.forename: S A
authors.initials: SA
authors.lastname: Silfverdal
authors.forename: L
authors.initials: L
authors.lastname: Bodin
authors.forename: M
authors.initials: M
authors.lastname: Ulanova
authors.forename: M
authors.initials: M
authors.lastname: Hahn-Zoric
authors.forename: L A
authors.initials: LA
authors.lastname: Hanson
authors.forename: P
authors.initials: P
authors.lastname: Olcén
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D001942:Breast Feeding; D005260:Female; D006192:Haemophilus Infections / Q000276:immunology*; D018073:Haemophilus Vaccines / Q000276:immunology; D019741:Haemophilus influenzae type b / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007130:Immunoglobulin Idiotypes / Q000096:biosynthesis* / Q000097:blood; D007223:Infant; D008297:Male
chemical_list: D000907:Antibodies, Bacterial; D018073:Haemophilus Vaccines; D007074:Immunoglobulin G; D007130:Immunoglobulin Idiotypes