title: Detection of ovomucoid-specific low-affinity IgE in infants and its relationship to eczema.
abstract: Allergen-specific low-affinity IgE was previously detected in cord blood by a highly sensitive densely carboxylated protein (DCP) chip, but not by ImmunoCAP. Here, we investigated the presence of low-affinity IgE during the early life of infants and observed its relationship with eczema.
  
  
  
  We conducted a birth cohort study, collecting sera at birth and 6 and 14 months of age (n = 110). We monitored the ovomucoid (OM)- and egg white (EW)-specific IgE (sIgE) by ImmunoCAP or DCP chip and analyzed the antigen affinity of sIgE by binding inhibition assays in the presence or absence of a mild chaotropic agent, diethyl amine (DEA). The low- and high-affinity OM-sIgEs and sensitization risk factors were analyzed by a multivariate logistic analysis.
  
  
  
  The OM-sIgE measured by DCP chip significantly correlated with that measured by ImmunoCAP, but some samples assessed as OM-sIgE positive by DCP chip were considered OM-sIgE negative by ImmunoCAP. Binding inhibition analysis after DEA treatment was performed for participants judged as OM-sIgE positive by DCP chip at 14 M. The group assessed as negative for OM- and EW-sIgE by ImmunoCAP at 6 and 14 months showed a larger binding inhibition curve shift after DEA treatment than did the group assessed as positive at these times, indicating the presence of low-affinity sIgE antibodies at 14 months. The logistic regression analysis found that persistent eczema from 6 to 14 months is a significant risk factor for developing high-affinity, but not low-affinity, sIgE.
  
  
  
  Human infant peripheral blood contains allergen-specific low-affinity sIgE. Persistent eczema is related to the development of high-affinity, but not low-affinity, IgE.
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Norio
authors.identifier: 0000-0002-3482-7781
authors.initials: N
authors.lastname: Kawamoto
authors.affiliation: Division of Enzyme Chemistry, Institute for Enzyme Research, Tokushima University, Tokushima, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Kamemura
authors.affiliation: Division of Enzyme Chemistry, Institute for Enzyme Research, Tokushima University, Tokushima, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kido
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fukao
mesh_terms: D000485:Allergens / Q000276:immunology*; D000915:Antibody Affinity; D015331:Cohort Studies; D004485:Eczema / Q000175:diagnosis / Q000276:immunology*; D021181:Egg Hypersensitivity / Q000175:diagnosis / Q000276:immunology*; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007223:Infant; D008297:Male; D010059:Ovomucin / Q000276:immunology*; D012307:Risk Factors
chemical_list: D000485:Allergens; D010059:Ovomucin; D007073:Immunoglobulin E
keywords: affinity maturation; birth cohort study; eczema; low-affinity IgE; ovomucoid