Differential gene expression profiling of human mast cells following IgE/antigen stimulation: Functional genomics analysis of selected novel genes.
Aggregation of the high affinity receptor for IgE (FceRI) on Mast cells triggers release of histamine containing granules, the synthesis of arachidonic acid-derived mediators and various cytokines, which together are responsible for the major symptoms of immediate (type I) hypersensitivity reactions.
The clinical consequences of type I hypersensitivity, triggered by mast cells, can range from localized reactions including allergic rhinitis, asthma, atopic dermatitis and food allergies, to severe life-threatening systemic reactions such as anaphylaxis. Although defined as localized reactions, asthma can also be fatal. Mast cell activation is the central mechanism in each of these reactions. Thus, dissecting the regulatory circuitry of mast cells by analysing the genome-wide effects of antigen/allergen stimulation triggered by FceRI, offers the potential for finding novel genes as “druggable targets” for therapeutic intervention.
We are using a wide range of techniques including DNA microarrays to analyse the differential gene expression pattern on activated mast cells. We use bioinformatics to mine existing data bases and to generate our tools to set up our own data base of differentially expressed genes. This is enabling us to classify and cluster genes by functional families, as well as to curate known genes in signaling pathways. Under this setting should also be able to select candidate “novel” genes for cloning and functional genomics analysis. This should allow us to identify and validate potential new targets for drug development.
Our goal is to find new target-genes of mast cell activation with the aim to create the possibilities for novel therapies to treat allergic diseases such as asthma. In order to achieve this aim, we plan to fully dissect the regulatory pathways of mast cell activation by analysing the genome-wide effects of antigen stimulation of human mast cells. The initial aim of the study is to determine the genetic expression profile of stimulated versus non-stimulated (control) cells. Following that, an initial identification of novel candidate-genes will be carried out using bioinformatics. Moreover, cell-based functional genomics assays will be carried out, using oligonucleotides-based antisense or siRNA, in order to establish the function of the novel genes.
We hope to gain insights into: