Allergens of the imported fire ant

Area of Science:

• Immunology
• Allergology
• Entomology

Background:

• Hypersensitivity to imported fire ants (IFA) is a significant health concern.
• Characterizing IFA allergens is crucial for diagnosis and treatment of allergic reactions.

Purpose of the Study:

• To identify and characterize allergens present in whole body extracts (WBE) of imported fire ants (IFA).
• To compare IFA allergens with those found in commercial IFA venom preparations.
• To investigate the molecular weight and IgE binding properties of IFA allergens.

Main Methods:

• Preparation of IFA whole body extract (WBE).
• Crossed immunoelectrophoresis (CIE) and crossed radioimmunoelectrophoresis (CRIE) using rabbit antiserum and patient sera.
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting to determine molecular weights and IgE reactivity.

Main Results:

• Six distinct allergen groups were identified in IFA WBE, with two classified as major allergens.
• Three IFA WBE allergens were also found in commercial IFA venom.
• Immunoblotting revealed human IgE binding to four protein bands (13-42 kDa), comparable in size to significant aeroallergens.

Conclusions:

• Imported fire ant whole body extract contains multiple allergens, including major ones.
• The identified IFA allergens share characteristics with known aeroallergens, suggesting potential cross-reactivity.
• These findings contribute to a better understanding of IFA allergy diagnosis and immunotherapy.