[Atopic dermatitis and Malassezia species: a study of antigenic components of Malassezia species for immunoglobulin E of patients with atopic dermatitis].
Antigenic components extracted by treatment with beta-mercaptoethanol from M. furfur, M. globosa, M. restricta, M. slooffiae, and M. sympodialis were studied for immunoglobulin E antibodies in sera of patients with atopic dermatitis. CBB staining and lectin blots of the extracts showed that each Malassezia species contained species-dependent components at the protein level. In a Western blot with the 2-ME extracts,IgE antibodies against the Malassezia species were found in sera of 83% (for M. globosa), 74% (for M. sympodialis), 65% (for M. furfur), 56% (for M. restricta) and 50% (for M. slooffiae) of the AD patients. In the Western blot inhibition test, the 2-ME extract of M. globosa partially inhibited the reaction of the antigenic components of other Malassezia species with the patients IgE antibodies. These results indicated that Malassezia species contained both species-specific and common antigenic components at the IgE antibody level. A major component of M. globosa was isolated from the 2-ME extract of this fungus by ion-exchange column chromatography and was referred to as Malg46b. Dot blot with the Malg46b containing fraction immunologically reacted with 69% of the sera of the patients, and with 83% of the sera of those who were positive for IgE antibodies to the 2-ME extract of M. globosa in Western blot. The intensities generated for each dot correlated well with the total intensities generated for the 2-ME extract of M. globosa in Western blot (r=0.763) The polyclonal antibody to Malg46b reacted strongly only with the 2-ME extract of M. globosa and reacted slightly with M. restricta. These results indicate that 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.
Laboratory of Medical Mycology, Research Institute for Disease Mechanism and Control, Nagoya University Graduate School of Medicine, 65 Tsurumai, Showa-ku, Nagoya, Aichi 466-8550, Japan.
Toshio
T
Kanbe
Tomoki
T
Koyama
D000908:Antibodies, Fungal / Q000097:blood*; D000946:Antigens, Fungal / Q000032:analysis; D003876:Dermatitis, Atopic / Q000276:immunology*; D003881:Dermatomycoses / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008290:Malassezia / Q000145:classification / Q000276:immunology*
D000908:Antibodies, Fungal; D000946:Antigens, Fungal; D007073:Immunoglobulin E