Development of in-vitro tests for drug allegernicity and b cell switching to ige synthesis

Objective

The aim of this proposal is to develop in-vitro tests that are predictive of the capacity of drugs to induce allergic reactions in man. The processes that lead to antibody production by B cells in response to primary drug allergen exposure, culminating in IgE synthesis, will be modelled in-vitro using lymphoid cells of human origin. The methods to be used will draw extensively on novel in-vitro technology. Ultimately the aim is to simplify the system, for example by the use of cell lines, such that it may be easily developed as a test for screening of drugs for allergenicity.
The project is divided into 5 interactive Work Packages tWP) that are designed to meet the above scientific objectives. Throughout the project beta-lactam antibiotics will be used as model compounds since they are known to conjugate spontaneously to proteins to generate allergenic epitopes without requirement for metabolic activation.
In WP 1 the plasma protein and cellular peptide targets for drug conjugation will be characterised using immunochemical and molecular biological techniques. In particular the possibility that beta-lactam drugs may conjugate directly to MHC class II molecules will be investigated. These conjugates will be made available to WP 2-5.
In WP 2 the responses of antigen-presenting cells to drugs and drug-derived peptides will be studied in terms of cytokine expression and surface adhesion molecule expression.
The responses of drug-specific human T cells in terms of patterns of cytokine expression, surface adhesion molecule expression and activation of transcription factors will be studied in WP 3.
In WP 4 T cell clones will be derived from drug-allergic patients. Patterns of cytokine and adhesion molecule expression will be studied, and compared with primary cultures.
Optimal conditions for generation and activation of drug- specific T cells will be established in WP 3 and WP 4 and subsequently these cells and techniques will be transferred to WP 5.
In WP 5 primary B cell antibody production to drugs will be induced using B cells stimulated via CD40 in the presence of interleukins-4 and -13 and composite peptides incorporating B cell and T cell drug-derived epitopes. The signals required for IgE switching will be identified. This system will provide the basis for development.

Programme(s)

• FP4-BIOTECH 2 - Specific research, technological development and demonstration programme in the field of biotechnology, 1994-1998

Topic(s)

• 070103 - In vitro tests for immuno-pharmaco-toxicology

Funding Scheme

Coordinator

Participants (5)