Among 616 eight year old children in an unselected birth cohort the authors found strikingly different IgG4/IgE ratios to milk and peanut components. This finding was additionally related to discordant results between an extract and microchip component IgE assay.
J. Allergy Clin. Immunol.
Allergen sensitization in a birth cohort at mid-childhood: focus on food component IgE and IgG4 responses.