Allergy Testing and Diagnostics: 2022 Workshop Summary
Last Updated: 28th December 2022 · Written by Felicia Oladipo
Lifelab Testing’s Bioscientist, Felicia Oladipo attended the Allergy and Diagnostics Workshop on Thursday, 13th October 2022 and found very useful and interesting current data from the session. The workshop was held at the EuroImmun International Training Centre in London. The topics covered in this intensive course included allergy pathogenesis, allergy diagnostics, allergy management, allergy extracts and components, cross-reactive carbohydrates determinants (CCD) and cross-reactivities, allergy immunoblots, and state of the art automated solutions for allergy testing.
Why is this research critical? The recent data has predicted that by 2025, approximately half of the entire EU population will be affected by at least one chronic allergic disease, therefore it is critical that we understand these immunological reactions.
That’s why this article will recap some of the key findings and themes discussed during the conference, and touch on what this might mean for health care businesses in the allergy industry, affected patients and within the larger immunological world.
Presentation 1 – Delivered by Nuran Eslik
Allergy Introduction and Evaluation
The opening presentation covered exactly how the body reacts when introduced to an allergen, which is a crucial area of study that can impact the allergen testing process and suitable treatment or prevention.
The first key observation introduced was that when it comes to a hypersensitivity reaction, the IgE mast cell is activated, and the symptoms usually appear within 15-30 minutes.
The body responds by causing symptoms such as:
- Hay fever.
- Eczema.
- Urticaria.
- Conjunctivitis.
- Asthma.
- Anaphylaxis.
Key takeaways
The latest industry data suggests that allergies are becoming more prevalent, especially for individuals under 18 years old. It is evident that most allergic patients are polysensitized, with around 60% of the patients being allergic to more than one allergen.
This presentation also showed us data that predicts that half of the entire EU population will be affected by a chronic allergic disease by 2025. It is more important now, than ever before, for people to improve their knowledge on how to identify allergies from their symptoms.
Allergy Testing
Then the presentation dove deeper into the IgE mast cell activation which, as mentioned, can produce physiological symptoms from allergic reactions, typically appearing within 15-30 minutes.
The current allergy blood test measurements that the technology of today allows for can detect an allergic reaction by testing IgE levels, but scientists haven’t been able to put their finger on is the exact cause or possible pathways behind allergic behind the allergic reactions.
There are, however, different types of diagnostics available to aid the detection of possible allergens. The methods discussed in this seminar include:
- Euroline: An extract-based diagnostics. It can, for example, include collecting parts of birch pollen that result in allergy symptoms and coating it on a nitrocellulose strip.
- Allergen-specific IgE: This is an efficient allergy diagnostic. It can include up to 54 allergens in one test strip. In this case, a low serum sample volume is required, fully automated performance and evaluation, and various profiles (allergens) are available for testing. At Lifelab Testing, we use this method of diagnosis in our at home allergy tests.
- Country-specific profiles: In this case, you can focus more on allergens that are more common in those countries/regions. In this case, you can have purified allergens on a membrane chip, ensuring an optimal membrane for each antigen. You can also have a combination of various allergens bringing about a fixed allergen position leading to easy evaluation.
Whether new methods are to be established remains unclear, however IgE testing is clearly growing particularly in the UK and EU.
Other noteworthy themes emerging from the presentation included:
Issues with cross-reactive carbohydrate determinants
Cross-reactive carbohydrate determinants (CCD) are protein-linked structures that are responsible for cross-reactivity. In allergy testing, CCDs can cause issues such as:
- Defined partial allergen diagnostic.
- Diagnostics based on single allergen components (partial allergens).
- Multiple sensitizations.
- Unclear results.
- Clarification of cross-reactions.
- Risk assessments.
- Therapy decisions.
Limitations of allergen extracts
A lot of in vitro allergy testing are still based on allergen extracts obtained from natural allergen sources. Allergen extracts are disadvantageous because of:
- Varying labs and tests. Different labs have different standards or use different components of plants to determine the allergy.
- DPA-Dx standardisation of the quantity of allergen components can be more expensive.
Definition of DPA-Dx
DPA-Dx allows accurate identification of the allergen-causing component (s). This additional detection does not base diagnostics on solely specific IgE antibodies in the serum, but also on recombinantly produced individual proteins (components)
What is the clinical significance of this research?
EuroImmun say “Molecular allergy diagnostics detect specific IgE antibodies in serum. The detection, however, is not based on total extracts of the allergen sources as conventionally, but on recombinantly produced individual proteins.”
This enables the following:
- Prognosis of possible tolerance development
- Risk assessment and estimation of the severity of allergic reactions
- Selection of a suitable specific immunotherapy
- Delimitation of (CCD-dependent) cross-reactions and genuine multiple sensitisations
EuroImmun offers inhalation, foods and insect venom DPA-Dx Profiles for simultaneous testing of all relevant components of the respective allergen sources.
Major vs Minor Allergens
Another key distinction for those in the allergy industry to note, is that allergens can be classified as either ‘major’ or ‘minor’ based on their IgE-binding frequency. Below, we outline the difference between significant allergens and minor allergens.
Major allergens
Major allergens have characteristics like:
- React in more than 50% of patients.
- Specific for a particular allergy.
- Often highly abundant in the allergen source.
Minor allergens
Minor allergens, on the other hand:
- React in less than 50% of patients.
- Trigger for cross-reactions.
- Often low abundance in the allergen source.
Cross-reactivity can occur due to the similar structure of the allergens (for example, botanical relations). This can therefore make you seem that you are allergic to other things that have a similar molecular structure.
Low-risk sensitisations
In the case of sensitisation to low-risk components, targeted dietary advice includes looking at the:
- Strength of DPA-Dx.
- Standardisation of tests.
- Detection of major and minor components.
- Detection of the most important protein families.
- Differentiation of cross-reactions vs true polysensitisation.
- Indication for the severity of clinical symptoms.
- Improved risk assessments for individual patients.
- Advisory for dietary restrictions/cooking.
It is hoped by that pursuing and developing these methodologies, IgE testing can become even more accurate and reliable; consistently delivering actionable results to patients.
Presentation 2 – Delivered by Nuran Eslik and Lucrezia Perazzotti
Immunoblots: Incubation and Evaluation
This presentation included showcasing the Euroline allergy test kit and choosing the optimal membrane for the allergen on the strip when testing. This presentation also involved a tour around the International Training Centre and an explanation of the different immunodiagnostic instruments in the second presentation and how to prepare samples for testing on such machines (Euroline allergy test kit) and their benefits. This demonstration was useful in comparing our own tests at Lifelab Testing to others in the industry.
References
- Eurimmune, DPA-Dx https://www.euroimmun.co.jp/products/allergy-diagnostics/id/dpa-dx/
