Biomarker: G006-IgE Timothy Grass

Overview

G006-IgE Timothy Grass measures serum immunoglobulin E (IgE) antibodies specific to Timothy grass pollen (Phleum pratense). IgE contributes to allergic inflammation by recognizing an allergen and triggering mediator release from sensitized immune cells. A detectable or elevated result indicates sensitization to Timothy grass, but it does not by itself confirm symptomatic allergy or predict reaction severity. The test is clinically useful when interpreted with exposure history and symptoms to help evaluate seasonal allergic rhinitis, allergic conjunctivitis, and related respiratory allergy.

Clinical Use Cases

Evaluate suspected Timothy grass or seasonal grass-pollen allergy.
Support assessment of allergic rhinitis, conjunctivitis, or asthma associated with grass-pollen exposure.
Identify relevant sensitization when considering allergen-specific immunotherapy.
Complement clinical history and, when appropriate, skin-prick testing.
Provide an alternative to skin testing when skin disease, medication use, age, or risk of a severe reaction limits skin testing.

Specimen Types

Venous blood, typically submitted as serum.
Capillary blood may be used in some validated collection systems, but venous serum is the standard clinical specimen.

Measurement Methods

Allergen-specific immunoassays performed on serum.
Fluorescence enzyme immunoassay.
Enzyme-linked immunosorbent assay and related solid-phase immunoassays.
Skin-prick testing with Timothy grass extract is an alternative in vivo method for assessing IgE-mediated sensitization, but it does not measure serum G006-IgE directly.

Test Preparation and Influencing Factors

Fasting is generally not required for an allergen-specific IgE blood test.
Patients should report all medications, particularly antihistamines and other allergy treatments. Medications that interfere with skin testing generally do not prevent blood collection, but medication decisions should be made by the healthcare provider.
Results should be interpreted with symptom timing, geographic and seasonal pollen exposure, and clinical history.
A positive result indicates sensitization and may occur without clinically relevant symptoms.
The measured IgE concentration does not reliably predict the severity of a future allergic reaction.
Total IgE elevation, smoking, parasitic infection, and nonspecific assay effects may complicate interpretation in some patients.
Results may vary among assay platforms and should be interpreted using the reporting laboratory’s reference categories.