Sensitization to the Yeast Malassezia Sympodialis Is Specific for Extrinsic and Intrinsic Atopic Eczema

Abstract

The opportunistic yeast Malassezia sympodialis belongs to the normal cutaneous flora but can also cause IgE-mediated sensitization in patients suffering from atopic eczema (AE). We investigated 706 individuals by ImmunoCAPm70 and skin-prick tests with a crude M. sympodialis extract. In AE patients, we further performed skin prick tests, atopy patch tests, ELISA, and peripheral blood mononuclear cells proliferation assays with recombinant M. sympodialis allergens (rMala s 1 and 5-9). In 52/97 patients with AE-specific IgE against M. sympodialis was detectable. Almost no reactivity to M. sympodialis was seen in patients suffering from other allergic diseases (4/571) and no reactivity at all was seen in healthy controls (0/38). Skin tests showed variable recognition patterns against the different molecular structures with a predominant sensitization to rMala s 1, 5, 6, and 9, confirmed also by specific serum IgE to these allergens. Interestingly, IgE- and T-cell-mediated reactivity against M. sympodialis was also found in patients with the intrinsic form of AE. Thus, sensitization to M. sympodialis is specific for AE patients and occurs in both the extrinsic and intrinsic variant of eczema. Recombinant yeast allergens represent a useful tool to study molecular structures and differential sensitization patterns in the pathogenesis of AE.

Clinical differences between atopic and atopiform dermatitis

“…29 Third, patients may not be sensitized for inhalant or food allergens, but for microorganisms such as Staphylococcus aureus or Malassezia sympodialis, which are not detected by routine allergen panel tests. 40,41 In addition, absence of allergenspecific IgE can be explained by as yet unidentified allergens. For example, sensitization may exist for airborne fungal antigens derived from the Coprinus comatus.…”

Sensitization to fungal allergens: Resolved and unresolved issues

“…Analysis by ELISA indicated that the frequencies of positivity for IgE Abs to rMala s 1, 5, 6, 7, 8, and 9 were 39, 47, 55, 10, 31, and 61%, respectively, indicating that Mala s 1, 5, 6 and 9 are the predominant allergenic components. 129 …”

“…147 In contrast, Mala s 1, 7, 8, and 9 are considered to be specific allergens with unique sequences. 129,144,148,149 Casagrande et al investigated the frequency of sensitization to a panel of recombinant M. sympodialis allergens (rMala s 1 and 5e9) in 51 patients with atopic eczema who were positive for IgE Abs to crude M. sympodialis (ImmunoCAP m70). Analysis by ELISA indicated that the frequencies of positivity for IgE Abs to rMala s 1, 5, 6, 7, 8, and 9 were 39, 47, 55, 10, 31, and 61%, respectively, indicating that Mala s 1, 5, 6 and 9 are the predominant allergenic components.…”

Mold and Human Health: Separating the Wheat from the Chaff

“…have gathered attention in AD pathogenesis, and several studies have demonstrated that patients with AD have more reactive skin testing to Malassezia spp., more reactive to atopy patch testing to Malassezia spp., and have higher titers of Malassezia spp. specific IgE [52,[55][56][57]. Furthermore, positive skin prick testing against Sacchromyces cerevisiae has also been reported in patients with AD [40].…”