Biomarker: F088-IgE Lamb

Overview

F088-IgE Lamb measures serum immunoglobulin E (IgE) antibodies specific to lamb, indicating immune sensitization to lamb-related allergens. IgE participates in immediate hypersensitivity reactions and can contribute to symptoms such as hives, gastrointestinal symptoms, wheezing, or anaphylaxis. A high result may indicate sensitization, but it does not by itself confirm clinical lamb allergy or predict reaction severity. The test is clinically useful when interpreted with exposure history, symptoms, and other allergy evaluation findings.

Clinical Use Cases

Support evaluation of suspected immediate allergic reactions after eating lamb.
Assess possible sensitization to mammalian meats in patients with suspected meat allergy.
Contribute to evaluation of reactions that may be related to alpha-gal syndrome, particularly when symptoms occur several hours after eating lamb or other mammalian products.
Help evaluate patients who cannot undergo skin-prick testing or when blood-based testing is otherwise preferred.
Monitor sensitization over time in selected clinical or research settings.

Specimen Types

Serum.
Plasma, depending on the laboratory method and validated collection requirements.

Measurement Methods

Allergen-specific IgE immunoassay.
Fluorescence enzyme immunoassay.
Enzyme-linked immunosorbent assay.
Older radioallergosorbent testing, commonly referred to as RAST.
Skin-prick testing with lamb extract may provide complementary evidence but does not measure circulating F088-IgE directly.
Alpha-gal-specific IgE testing may be used separately when delayed reactions to lamb or other mammalian products raise concern for alpha-gal syndrome.

Test Preparation and Influencing Factors

Fasting is generally not required for a specific IgE blood test.
Report all medications and supplements to the ordering clinician. Do not stop medicines unless instructed.
Antihistamines can interfere with skin-prick testing, but they generally do not affect blood-based specific IgE measurement.
Results should be interpreted with the timing, reproducibility, and severity of symptoms after lamb exposure.
A positive result indicates sensitization and may occur without clinical allergy.
Cross-reactivity among mammalian meat allergens can produce positive results to more than one meat.
Total IgE concentration, smoking, parasitic infection, and other allergic conditions may affect interpretation of IgE results.
A negative result does not completely exclude allergy.
The concentration of lamb-specific IgE does not reliably predict reaction severity.
Alpha-gal syndrome should be considered separately because reactions to lamb may be delayed by approximately 2 to 10 hours and require compatible symptoms plus alpha-gal-specific IgE evidence for diagnosis.