Three major components of Malassezia globosa were isolated from 2-ME extracts of this fungus by ion-exchange column chromatography and are referred to as Malg46a, Malg46b and Malg67, respectively. IgE antibodies to these components in the sera of patients with AD were detected by immunoblots. In Western blot, IgE antibodies to Malg46b were most frequently detected in the sera of AD patients. Dot blot with the Malg46b-containing fraction immunologically reacted with 69% of the sera of the patients, and with 83% of the sera of the patients who were positive for IgE antibodies to the 2-ME extract of M. globosa in the Western blot. The intensities generated for each dot correlated well with the total intensities generated for the 2-ME extract of M. globosa in the Western blot (r=0.763). In the lectin blot, Con A reacted with both Malg46a and Malg46b but not with Malg67. The polyclonal antibody to Malg46b reacted strongly only with the 2-ME extract of M. globosa and reacted slightly with M. restricta. In conclusion, a glycoprotein, Malg46b of M. globosa, is dominantly expressed in this fungus and is a possible major antigen for IgE antibodies in patients with AD.Key words: Malassezia globosa, Atopic dermatitis, IgEThe lipophilic fungus Malassezia furfur (also called Pitvrosporuin orbiculare and P ovale) is often isolated as a common commensal from the surface of healthy human skin (11) or patients with atopic dermatitis (1). Many investigators have focused on the involvement of M. fitrfur in AD because immunoglobulin E antibodies specific for M. furfur were frequently found in patients with AD (14, 18), and several antigenic components of this fungus have been reported (4,7,8,12,15).More recently, the genus Malassezia was classified into 7 species, M. svinpodialis, M. globosa, M. restricta, M. sloolfiae, M. furfur, M. obtusa and M. pachydennatis, by their morphological, biochemical and genetic characteristics (2, 16). However, the association of the new Malassezia species with AD and their major antigenic components which react with IgE antibodies in the sera of AD have not been examined.We have isolated Malassezia from patients and identified their species based on new classification methods (3, 13). In our previous study, IgE antibodies to M. globosa were often found in patients with AD and the IgE antibodies reacted frequently with ca. 46 kDa or ca. 67 kDa bands in Western blotting (manuscript submitted for publication). This suggests that these components are possible major antigens for IgE antibodies in patients with AD. We believe that defining the major antigenic components for the IgE antibodies of M. globosa will give us information useful not only for understanding the mechanism of AD but also for diagnostic standardization. The goal of our work is to define the major epitopes of the major allergens of Malassezia species for IgE antibodies in patients with AD. In this paper, we isolated a possible antigenic component for IgE antibodies from M. globosa and describe its character-