Background Candida albicans crossreacts with Saccharomyces cerevisiae or Pityrosporum ovate at the IgE level. However, the extent of crossreactivity of C. alhicans with other yeast species is not known.
Objective The crossreactivity at the immunoglobulin E (IgE) level of Candida alhicans with other pathogenic Candida species and to the airborne yeast species Cryptococcus and Rhodotorula was studied by immunoblot analysis.
Methods Crude antigens, designated as heat extract, were prepared from 13 different yeast species and a dot blot test was performed to detect IgE antibodies against each of the heat extracts in 349 patients with allergies who were positive for IgE antibodies against C alhicans in a CAP system.
Results In the dot blot test, most of the sera reacted with the heat extracts of not only C. albicans but also those prepared from the other yeast species. The sera of 41 of the 349 patients (11.7%) reacted with the heat extracts of all 13 yeast species. The extent of the binding of IgE antibodies to multiple yeast species correlated with both the fluorescence intensities measured in the CAP system and the intensities of dots generated by the heat extract of C. alhicans in the dot blot test. In an inhibition dot blot test, mannoproteins. but not proteins, of C. albicans strongly inhibited the subsequent binding of IgE antibodies to all yeast species.
Conclusion Our data suggest that the C. albicans mannoproteins are responsible for the crossreactivity among these yeast species at the IgE level.