Immunoglobulin subclass distribution of specific antibodies in allergic patients

The IgG and IgA subclass distribution of specific antibodies against a variety of protein and polysaccharide antigens was determined in sera from individuals with high levels of IgE. No shift of the antibody pattern could be observed, suggesting that the aberrant regulation of responses against allergens noted in these patients is limited, encompassing selected antigens only. Antibodies against protein antigens are mainly of the IgG1 subclass. In addition, low levels of specific IgG3 or IgG4 antibodies may be formed. Our data suggest that a given antigen induces either IgG3 or IgG4 and that potential allergens, in addition to IgG1 and IgE, elicit a response restricted to IgG4.