Specific IgG antibodies to Dermatophagoides pteronyssinus and egg white--their changes with age

Dermatophagoides pteronyssinus-specific and egg white-specific IgG in 232 children and 42 adults were measured by the RAST method using monoclonal anti-human IgG antibodies (HG2-25) as the secondary antibody. Changes in allergen-specific IgG with the age of the subjects were examined. Allergen-specific IgG antibody in standard serum was designated as 1,000 U/mL. Standard curves were made for each measurement and the levels of allergen-specific IgG of the sera were expressed in units (U). Dermatophagoides pteronyssinus-specific IgG increases from 9 months of age until adulthood. The atopic group showed higher mean values than the non-atopic group (r less than .001). Egg white-specific IgG reaches a peak around 3 to 4 years of age. After this, it declines until adulthood. These results suggest that age factors and allergen factors must be taken into consideration when evaluating allergen-specific IgG antibodies.