Biomarker: T057-IgE Cedar, Red

Overview

T057-IgE Cedar, Red measures immunoglobulin E (IgE) antibodies in blood that specifically recognize red cedar pollen allergens. IgE is an antibody involved in immediate-type allergic responses, including allergic rhinitis after pollen exposure. A detectable or elevated result indicates sensitization to the tested cedar pollen extract, but it does not by itself establish symptomatic allergy or predict reaction severity. The test is clinically useful when interpreted with exposure history and symptoms to help evaluate seasonal allergic rhinitis and related respiratory or conjunctival symptoms.

Clinical Use Cases

Supporting evaluation of suspected red cedar pollen allergy and seasonal allergic rhinitis.
Identifying sensitization to a specific outdoor aeroallergen when symptoms correlate with pollen exposure.
Assessing patients who cannot undergo skin-prick testing because of extensive skin disease, dermographism, medication interference, or other clinical considerations.
Complementing skin-prick testing when clinical history and initial test results are discordant.
Supporting research on cedar-pollen sensitization, allergen-specific immune responses, and response to allergen immunotherapy.

Specimen Types

Venous whole blood, with serum used for most specific-IgE assays.
In selected research settings, nasal secretions may be analyzed for local cedar-pollen-specific antibodies, but this is not the usual specimen for routine T057-IgE testing.

Measurement Methods

In-vitro allergen-specific IgE immunoassay using a solid-phase cedar pollen allergen extract.
Fluorescent enzyme immunoassay or other enzyme-based immunoassay.
Chemiluminescent immunoassay, depending on the laboratory platform.
Older radioallergosorbent test terminology, or RAST, may be used historically for serum-specific IgE testing, although modern assays generally use nonradioactive methods.
Skin-prick testing with a red cedar pollen extract is a related in-vivo method for detecting cutaneous allergen-specific IgE, but it is not a measurement of serum T057-IgE.

Test Preparation and Influencing Factors

No special preparation or fasting is usually required for an allergy blood test.
Patients should report prescription medicines, over-the-counter medicines, vitamins, and supplements. Medicines should not be stopped unless directed by a healthcare professional.
Antihistamines can interfere substantially with skin-prick testing, but they generally do not prevent measurement of serum-specific IgE. Medication instructions should follow the ordering clinician’s guidance.
The result should be interpreted with symptom timing, geographic exposure, pollen season, and clinical history. A positive result indicates sensitization and does not necessarily indicate clinically relevant allergy.
The concentration of specific IgE does not reliably predict the severity of a future allergic reaction.
Different assay platforms, allergen extracts, reporting units, and classification thresholds may produce results that are not directly interchangeable.
Cross-reactivity among related cedar and other conifer pollens may contribute to positive results, so species-specific clinical correlation is important.