Biomarker: F236-IgE Whey

Overview

F236-IgE Whey measures serum allergen-specific immunoglobulin E (IgE) antibodies directed against cow’s-milk whey proteins. Whey contains proteins such as α-lactalbumin, β-lactoglobulin, and bovine serum albumin that can act as allergens in susceptible individuals. A detectable or elevated result indicates sensitization to whey, while a low or undetectable result makes IgE sensitization less likely but does not independently exclude allergy. The test supports evaluation of suspected IgE-mediated reactions to milk or whey, but results must be interpreted with the clinical history because specific IgE demonstrates sensitization rather than confirming clinical allergy or predicting reaction severity.

Clinical Use Cases

Support evaluation of suspected IgE-mediated allergy to cow’s milk whey.
Help investigate immediate symptoms after consuming milk, whey protein, infant formula, or other whey-containing products.
Complement a focused allergy history and, when appropriate, skin-prick testing.
Support assessment of sensitization to whey proteins, including α-lactalbumin and β-lactoglobulin.
Contribute to decisions about supervised oral food challenge when the diagnosis remains uncertain. The oral food challenge is the reference standard for confirming food allergy.

Specimen Types

Venous blood serum.
Plasma may be accepted by some assay systems, depending on the laboratory method and collection requirements.

Measurement Methods

In-vitro quantitative allergen-specific IgE immunoassay.
Fluorescence enzyme immunoassay or comparable solid-phase immunoassay.
Immunoassays using whole cow’s-milk whey extract as the allergen source.
Component-resolved immunoassays for individual whey proteins, such as Bos d 4, Bos d 5, and Bos d 6, when more detailed characterization is needed.

Test Preparation and Influencing Factors

Fasting is generally not required for an allergen-specific IgE blood test.
Tell the healthcare provider about all medications and supplements. Do not stop antihistamines or other medicines unless specifically instructed.
Collection timing generally does not require alignment with recent food exposure.
Recent illness, atopic dermatitis, asthma, parasitic infection, and other allergic conditions may influence total or allergen-specific IgE interpretation.
A positive result indicates sensitization and does not by itself establish clinical allergy, identify a reaction threshold, or predict reaction severity.
Test interpretation should consider the food history, timing and nature of symptoms, other allergy testing, and, when clinically indicated, a medically supervised oral food challenge.
Assay reporting units, detection limits, and decision thresholds may vary between laboratories.