The atopic syndrome: in vitro immunological characteristics of clinically defined subgroups of atopic subjects.

Total IgE, selected specific IgE antibody levels, C2 and yeast opsonization were measured in four clinically defined subgroups of atopic patients who had previously been HLA-typed. Each group was characterized by a distinctive mean total IgE level and profile of specific IgE responses. All groups gave comparable levels of IgE antibodies to Timothy grass pollen but in patients initially presenting with infantile eczema and who subsequently developed asthma and/or hay fever, IgE antibodies to bovine milk proteins, egg ovalbumin and cat dander were frequently observed whereas in patients initially presenting with hay fever later in life these antibodies were usually absent. Computer assisted analysis failed to show any association between IgE antibody responses and (a) the HLA phenotypes A1,B8 and A3,B7 (b) C2 levels and (c) the yeast opsonization index.