Human IgE mAbs define variability in commercial Aspergillus extract allergen composition.

Area of Science:

• * Medical Mycology
• * Immunology
• * Allergy and Clinical Immunology

Background:

• * Aspergillus species sensitization is linked to allergic respiratory diseases, including allergic bronchopulmonary mycosis.
• * Current allergen immunotherapy for Aspergillus relies on nonstandardized extracts, hindering consistent treatment.
• * A critical need exists for methods to standardize Aspergillus extracts for diagnostic and therapeutic use.

Purpose of the Study:

• * To develop and utilize Aspergillus-specific human IgE monoclonal antibodies (mAbs) for characterizing allergenic epitopes.
• * To assess the allergen protein content and variability in commercial Aspergillus fumigatus extracts.
• * To establish a foundation for the standardization of mold extracts.

Main Methods:

• * Recruitment of patients with allergic bronchopulmonary mycosis from Vanderbilt University Medical Center.
• * Generation and immortalization of human IgE-secreting B cells using novel hybridoma techniques.
• * Characterization of commercial Aspergillus extracts using 26 developed Aspergillus-reactive human IgE mAbs as capture and detection reagents.

Main Results:

• * Extreme variability was observed in the specificity and quantity of protein targets across commercial Aspergillus extracts.
• * Only 4 out of 26 human IgE mAbs reacted with all tested extracts.
• * The major Aspergillus allergen, Asp f 1, was present in only 1 of the 4 evaluated commercial extracts.

Conclusions:

• * The significant variability in commercial Aspergillus extracts likely impacts their efficacy in diagnosis and treatment.
• * Human IgE monoclonal antibodies offer an innovative approach to evaluating allergenic epitopes.
• * This research provides a pathway toward the development and standardization of Aspergillus extracts for clinical applications.