Reminder: 

ALEX® – Allergy Explorer 

ALEX is a next-generation test for the diagnosis of Type I (IgE-mediated) allergies, based on an exclusive nanobead technology that provides a comprehensive overview of each patient’s allergic sensitization profile, using a panel of more than 280 native allergen extracts and molecular allergens, complemented by total IgE measurement. 

Key Features 

  • Broad allergen panel, individually optimized 

  • Multiplex testing with customizable panel composition 

  • Integrated CCD (Cross-Reactive Carbohydrate Determinants) inhibition 

  • Simultaneous measurement of total and specific IgE 

Obtaining complete sensitization profiles using conventional singleplex systems can be challenging. In many cases, several rounds of testing are required to establish a clear diagnosis, and total IgE measurement must be performed separately. 

To streamline this fragmented approach, ALEX® provides a comprehensive overview of the patient's allergic status, including total IgE levels. 

Among the molecular allergens exclusively available within this panel are risk markers from major allergenic protein families, such as storage proteins, as well as novel markers (e.g., Malassezia sympodialis allergen components). 

The ALEX® protocol incorporates a highly effective CCD inhibitor during serum incubation, minimizing interpretation errors in patients with CCD-specific IgE positivity (a common cause of extensive in vitro cross-reactivity) and thereby increasing the specificity of test results. 

 

CLINICAL RELEVANCE 

The ALEX® test is intended to support the diagnosis of allergic diseases in conjunction with clinical history and complementary investigations (e.g., skin prick testing). 

ALEX® provides information regarding: 

  • Potential indications for allergen-specific immunotherapy 

  • Assessment of allergic risk to help prevent severe food allergic reactions 

  • Identification of cross-reactivities 

  • Detection of unsuspected allergen sensitizations 

 

INDICATION FOR IMMUNOTHERAPY 

Allergen-specific immunotherapy is a therapeutic approach for allergic diseases, particularly respiratory allergies and venom allergies. 

A diagnostic approach based solely on allergen extracts may yield positive results that reflect either genuine co-sensitization or cross-reactivity. The use of molecular allergens helps resolve this distinction and supports more accurate therapeutic decision-making. 

 

RISK ASSESSMENT AND CROSS-REACTIVITY EVALUATION 

Extract-based allergy tests have proven useful in identifying the allergen source involved. However, only an additional molecular approach can provide clinically relevant information to complement test results and support optimal therapeutic decisions. 

For example, storage proteins such as Ara h 1, Ara h 2, Ara h 3, and Ara h 6 may cause severe allergic symptoms, including anaphylactic shock. 

In contrast, the PR-10 protein Ara h 8 generally does not induce severe symptoms. It is often associated with birch pollen allergy because the major birch allergen Bet v 1 also belongs to the PR-10 family. This highlights the importance of detecting the full range of relevant molecular components. 

Similar situations are frequently encountered with other food allergens such as hazelnut, soy, and peach. 

 

DETECTION OF UNEXPECTED SENSITIZATIONS 

ALEX is a valuable tool for identifying allergen sensitizations that may not have been suspected based on patient history and/or skin testing. 

 

ALEX3 

Evolution of the Allergen Microarray: Transition from ALEX2 to ALEX3 

As part of our commitment to continuous improvement in allergy diagnostics, we are pleased to announce that, starting July 1st, 2026, our laboratory will implement the new generation ALEX3 multiplex microarray, which will progressively replace ALEX2. 

This new version introduces several significant improvements: 

  • Optimized allergen panels through a comprehensive review of included allergens 

  • Enhanced allergen selection to improve both sensitivity and specificity 

 

Expanded and Optimized Allergen Panel 

ALEX3 significantly enhances allergological investigation through an optimized selection of clinically relevant allergens and molecular components. 

Enhanced Molecular Precision 

  • More than 218 molecular allergens, including 109 exclusive components 

  • Addition of new molecular allergens with high clinical relevance, particularly for chicken, celery stalk, wheat, oak pollen, and honeybee venom 

  • Inclusion of emerging allergens whose clinical significance is currently being evaluated, such as lentil and pea 

  • Integration of new molecular components including α-Gal, Api g 7, Gal d 7, Len c 1 and 3, Pis s 1 to 3, Que a 1, Tri a 36, and Tri a 37 

 

Broader Allergen Coverage 

New Allergen Sources 

  • Freshwater shrimp 

  • Golden hamster 

  • Oak pollen 

  • Pine nuts 

 

New Molecular Families 

  • α-Hairpinins 

  • Cyclophilins 

  • Glutenins 

  • Hemocyanins 

  • Hyaluronidases 

 

New Analytical Features 

  • Integrated pipetting control for enhanced analytical process security and quality assurance 

  • Quantitative total IgE measurement directly incorporated into the assay 

 

A Design Driven by International Clinical Data 

The development of ALEX3 is based on the analysis of more than one million test results collected from over 90 countries. 

This approach has enabled: 

  • Optimization of the clinical relevance of the selected allergens 

  • Reduction of analytical redundancy through the selection of representative marker allergens for complete allergen families 

  • Improved coverage of sensitization profiles observed both globally and regionally 

 

Improved Diagnostic Relevance 

The selection of allergens included in ALEX3 is based on: 

  • Their positivity frequency observed in clinical practice 

  • Average levels of detected specific IgE 

  • Co-reactivity patterns within allergen families 

  • Representation of allergen sources encountered in different geographical regions 

This evolution aims to improve the characterization of sensitization profiles and strengthen diagnostic support for the management of allergic patients.