Reflective Practive


ImmunoCAP ISAC is a highly advanced tool for revealing the patient's IgE antibody profile. It is the result of a combination of innovative biochip technology and cutting edge research in molecular allergology. It is the only in vitro diagnostic test for simultaneous measurement of specific IgE antibodies to a broad spectrum of allergen components.

How do they work?

The biochip technology takes the form of a miniaturised immunoassay platform where allergen components are immobilised in a microarray. This enables measurement of IgE antibodies to a fixed panel of 112 components from 51 allergen sources in a single step, using only 30 μl of serum or plasma. The allergen components are spotted in triplets and covalently immobilised on a polymer coated slide. Each slide contains four microarrays giving results for four different samples per slide.

ImmunoCAP ISAC is a two-step assay:


IgE antibodies from the patient sample bind to the immobilised allergen components


Allergen-bound IgE antibodies are detected by a fluorescence labelled anti-IgE antibody

The test procedure (including washing and incubation steps) gives a total assay time of less than 4 hours. Fluorescence is measured with a laser scanner and results are evaluated using Phadia Microarray Image Analysis (MIA) software. ImmunoCAP ISAC Xplain is also available; it is the first result interpretation support system for molecular allergy diagnostics. The ImmunoCAP ISAC Xplain knowledge base is based on recent literature and has been approved by allergy specialists in more than 10 countries.

For each patient's allergens ImmunoCAP ISAC Xplain answers the following questions:

  • Is the molecule species-specific or cross-reactive?
  • Is the molecule stable and therefore also prone to elicit reactions to heated food?
  • Is the molecule commonly associated with no (asymptomatic), local or systemic reactions?
ImmunoCAP ISAC is a semi-quantitative test and results are reported in ISAC Standardised Units (ISU) giving indications of specific IgE antibody levels within a measuring range of 0.3-100 ISU-E. ISU-E are standardised to ImmunoCAP Specific IgE units.

Are you a laboratory professional?

This educational website, provided by Thermo Fisher Scientific, ImmunoDiagnostics Division, has been produced in partnership with the Institute of Biomedical Science as a pioneering venture to promote excellence in laboratory practice using education and continuing professional development (CPD) resources.

The information contained within this website is intended for laboratory professionals.

By entering this website you are confirming that you are a laboratory professional.

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