Characterization of Dac g 4, a major basic allergen from Dactylis glomerata pollen

Area of Science:

• Allergen research
• Immunology
• Biochemistry

Background:

• Dactylis glomerata pollen contains major basic allergens like Dac g 4.
• Understanding allergen structure and cross-reactivity is crucial for diagnosing and treating pollen allergies.

Purpose of the Study:

• To produce monoclonal antibodies against Dac g 4.
• To characterize Dac g 4 and assess cross-reactivity with other grass pollens.

Main Methods:

• Monoclonal antibody production.
• BIAcore analysis for antibody-allergen interaction.
• Mass spectrometry for molecular mass determination.
• SDS-PAGE and immunoblotting for protein analysis.
• ELISAs and IgE inhibition studies for cross-reactivity assessment.

Main Results:

• Monoclonal antibodies were successfully generated against Dac g 4.
• Dac g 4 has a molecular mass of 59,185 +/- 30 Da and an isoelectric point of 10.4.
• Dac g 4-related proteins were found in most allergenic grass pollens, comprising about 6% of total extractable proteins.
• One antibody recognized a cross-reactive 60 kDa protein in various grass pollens but not in tree or weed pollens.

Conclusions:

• Monoclonal antibodies are effective tools for Dac g 4 immunopurification.
• Dac g 4 exhibits significant cross-reactivity with allergens from other grass pollens, suggesting shared epitopes.
• These findings contribute to understanding grass pollen allergy mechanisms and diagnostics.