Using time-resolved fluorescence to measure serum venom-specific IgE and IgG

Area of Science:

• Immunology
• Allergy diagnostics
• Biochemical assays

Background:

• Australian native ant venoms, especially jack jumper ant venom (JJAV), are significant causes of allergic reactions.
• Accurate quantification of specific IgE (sIgE) and IgG subclasses (sIgG1, sIgG4) is crucial for diagnosing and managing ant venom allergies.

Purpose of the Study:

• To adapt the dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA) for quantifying venom-specific IgE, IgG1, and IgG4 antibodies.
• To evaluate the performance of the adapted DELFIA assay for detecting JJAV-specific IgE compared to established methods and skin testing.

Main Methods:

• Adaptation of the DELFIA time-resolved fluorescence immunoassay.
• Quantification of whole venom and peptide-specific IgE, IgG1, and IgG4 in serum samples.
• Comparison of DELFIA results with Phadia CAP assay and intradermal skin testing for JJAV-specific IgE.

Main Results:

• The DELFIA assay demonstrated good intra-assay (6.3% CV) and inter-assay (13.7% CV) reproducibility for JJAV sIgE.
• DELFIA showed excellent correlation with Phadia CAP assay for JJAV sIgE.
• The sensitivity and specificity of DELFIA for detecting JJAV sIgE were comparable to intradermal skin testing.

Conclusions:

• The adapted DELFIA assay is a reliable and sensitive method for quantifying specific antibodies to Australian native ant venoms.
• DELFIA offers a viable alternative for diagnosing ant venom allergies, with potential for adaptation to other venom allergens.