Analysis of differential gene and protein expression for in-vitro detection of drug allergy

A research project at the Federal Institute for Drugs and Medical Devices (BfArM) is dedicated to the improved detection of drug allergies. So far, the diagnostic possibilities in this field are limited; they are often costly or not meaningful. For this reason, the BfArM is researching a new test approach in a joint project with the Clinic for Dermatology and Allergology at the University Hospital RWTH Aachen, Life & Brain GmbH Bonn and the Leibniz Institute for Analytical Sciences (ISAS) based in Dortmund.

Background:

Drug allergies are a particularly relevant form of allergy, the frequency of which is likely to increase further due to demographic change. The diagnosis of drug allergies is currently based on

1. anamnesis and classification of the clinical reaction.

2. in vivo tests: ...prick and intradermal tests. These elaborate skin tests have limited sensitivity and are only standardized for a few active ingredients.

3. in vitro tests: Detection methods for specific antibodies (IgE) in instant type reactions are only available for a few drugs and are contrasted with cellular test systems such as the lymphocyte transformation test (LTT). However, the traditional LTT (read-out parameter: 3H-thymidine incorporation of the proliferating cells) is rather unsuitable for routine diagnostics.

4. provocation tests. However, these are not risk-free due to the danger of an allergic reaction and are therefore often rejected by patients. If there was a severe allergic reaction in the medical history, they are contraindicated.

In summary, there are currently no satisfactory diagnostic options for many drug-allergic reactions with a great need for a reliable method that can be used in routine diagnostics, which is safe for patients, not stressful and requires little time. In vitro tests are particularly suitable here, as they only require a blood sample to be taken and it is also easier to test several suspected drugs.

Project objectives:

The overall aim of the project is to investigate the basics by using modern, innovative methods, which should make it possible to develop an in vitro diagnostic test for the detection of drug allergies suitable for routine use in the future. For this purpose, the differential gene and protein expression of peripheral mononuclear cells (PMBC) of allergic patients will be analysed in comparison to non-allergic test persons after in vitro stimulation with the drug accused of the allergy.

Project description and methodology:

The project will initially examine patients with confirmed drug allergy and control persons without allergy to the drug in question. Peripheral mononuclear cells (PBMC) are isolated from their blood and co-cubated with the drug in question. After completion of the coincubation, gene and protein expression in the PBMCs is analyzed genome- and proteome-wide with respect to suitable target genes and/or their transcription products. After identifying suitable read-out parameters in the first project phase, their use will be tested on a larger number of patients in the second project phase.

The main work steps of the project are (lead partners in brackets)

1. Recruitment of patients with confirmed drug allergy and control persons without allergy to the drug in question (Clinic for Dermatology and Allergology, University Hospital RWTH Aachen)

2. the isolation of the peripheral mononuclear cells (PBMC) of the patients and controls and coincubation of the PBMC with the accused drug and the isolation of their RNA (Federal Institute for Drugs and Medical Devices, BfArM);

3. genome- and proteome-wide analysis of differential gene and protein expression (Life & Brain GmbH (Life & Brain); Leibniz Institute for Analytical Sciences (ISAS))

4. the identification of suitable target genes and/or their transcription products as read-out parameters (Life & Brain, ISAS)