Beyond Traditional Allergy Testing: The Role of ALEX in Precision Allergy Diagnostics

Allergic diseases are complex. While two patients may present with similar symptoms, the underlying allergens and molecular components driving those symptoms can be very different. As healthcare moves increasingly towards precision medicine, allergy diagnostics are evolving to provide clinicians with a more detailed understanding of an individual patient's sensitisation profile.

Research by Heffler et al. (2018) explored the use of ALEX (Allergy Explorer), a multiplex allergy testing platform designed to provide an extensive IgE profile using both allergen extracts and molecular allergen components. The researchers describe this combination as a potentially valuable approach to supporting more personalised allergy diagnosis and management.

From identifying an allergy to understanding sensitisation

Traditional allergy diagnostics commonly begin with a patient's clinical history, physical examination and skin-prick testing. Specific IgE testing against whole allergen extracts may then provide further information.

Molecular allergy diagnostics take this a step further by investigating the individual allergen components to which a patient has developed IgE antibodies. This can help clinicians distinguish between genuine sensitisation to a particular allergen and sensitisation resulting from cross-reactivity between structurally similar allergen components (Heffler et al., 2018).

This distinction can be particularly important in patients with complex allergy profiles.

A broader picture from a single assay

In the version evaluated by Heffler et al. (2018), ALEX incorporated 282 reagents, consisting of 157 allergen extracts and 125 molecular components. These represented a broad range of allergen families, including inhalant allergens, foods, pollens, mites, pets, moulds, latex and insect venoms.

A key feature highlighted by the researchers was ALEX's ability to combine information from whole allergen extracts and relevant molecular components within the same assay.

According to Heffler et al. (2018), this combination can help establish not only whether IgE sensitisation is present, but also whether the response may represent genuine sensitisation or cross-reactivity. The authors considered this particularly useful for building a more comprehensive IgE profile.

What did the research find?

The study analysed serum samples from 43 patients with allergies and compared ALEX results with those obtained using ImmunoCAP ISAC.

Despite methodological differences between the two platforms, the researchers found that the molecular allergen IgE profiles detected by ALEX and ISAC were generally similar, with significant correlations observed across the comparisons performed. The researchers also found consistency between many whole-allergen extract results and their relevant molecular components (Heffler et al., 2018).

Importantly, the authors acknowledged differences between the platforms, including differences in dynamic range and the use of a cross-reactive carbohydrate determinant (CCD) inhibitor by ALEX. The CCD inhibitor is intended to reduce IgE binding related to CCD cross-reactivity, potentially helping to improve analytical specificity (Heffler et al., 2018).

Why could this matter for patients with complex allergies?

For patients sensitised to multiple allergens, interpreting allergy test results can be challenging. A positive result does not always mean that each identified allergen represents an independent, clinically relevant allergy.

This is where molecular-level information can add value.

By examining both allergen extracts and their components, clinicians may gain greater insight into the patient's individual sensitisation pattern. Heffler et al. (2018) suggested that this approach may be particularly valuable for polysensitised patients and patients with pollen-food syndromes, where distinguishing genuine sensitisation from cross-reactivity can be especially relevant.

Ultimately, laboratory results remain one part of the diagnostic process and should be interpreted alongside the patient's clinical history and other relevant clinical findings.

Supporting the move towards precision allergy diagnostics

The study by Heffler et al. (2018) demonstrates how multiplex molecular allergy diagnostics can contribute to the broader movement towards precision medicine.

Rather than looking at allergy simply as a positive or negative response to an allergen, extended IgE profiling provides an opportunity to examine the underlying pattern of sensitisation in considerably greater detail.

For laboratories and healthcare providers, technologies such as the ALEX platform therefore represent an opportunity to expand molecular allergy diagnostic capabilities and support clinicians with more comprehensive allergy information.

Interested in bringing ALEX testing to your laboratory?

Diagno provides access to ALEX allergy diagnostic technology and can assist laboratories and healthcare organisations interested in implementing the ALEX analyser and associated testing solutions.

Contact the Diagno team to learn more about the ALEX platform, analyser options and how molecular allergy diagnostics could be incorporated into your diagnostic offering.

This article is intended for educational and informational purposes and is based on the research cited below. Diagnostic test results should always be interpreted by appropriately qualified healthcare professionals.

Reference

Heffler, E., Puggioni, F., Peveri, S., Montagni, M., Canonica, G. W., & Melioli, G. (2018). Extended IgE profile based on an allergen macroarray: A novel tool for precision medicine in allergy diagnosis. World Allergy Organization Journal, 11, Article 7. https://doi.org/10.1186/s40413-018-0186-3