The main objective of our research is to achieve detailed understanding of the molecular and cellular mechanisms underlying immunological disease initiation, progression and chronicity. The goal of this research is (i) to develop more accurate animal models of mechanisms underlying chronic inflammation and autoimmunity and (ii) to disclose new diagnostic markers and therapeutic targets for this class of diseases.

We have previously developed and established:
(i) Τechnologies for permanent or conditional genome modification in the mouse
(ii) TNF-driven transgenic or mutant animal models of chronic inflammatory polyarthritis, Crohn’s-like inflammatory bowel disease, systemic inflammation and autoimmune demyelination / multiple sclerosis
(iii) Basic knowledge on mechanisms in immunity, inflammation, tolerance and autoimmunity.

In continuation of this previous work, we aim to continuously improve the current state of the art in the understanding of aetiology, pathophysiology, progress and outcome of disease by using:
(i) conditional and/or tissue-specific targeted mutagenesis in mice to study the impact of ablating specific cells, genes and pathways in our own animal models developing specific immunological diseases;
(ii) differential gene expression analysis (DNA microarrays or gene chips) on important pathogenic cell types to discover new genes with putative involvement in disease;
(iii) sensitized phenotypic screens combined with chemical (ENU) mutagenesis in the mouse to search for novel genes that will neutralize pathology.

With these aims and objectives we hope to maintain and further develop our excellence in biomedical/genomic/biotechnological know-how that will constitute the sole ground for the development of new biological concepts and will lead to the introduction of more rational forms of therapies in the coming decade.

More specifically, our aims are:

1. To identify cells, genes and pathways with dominant contributions to disease initiation, progression and chronicity. Conditional gene targeting in mice offers an unparalleled tool to study the involvement of specific cells, genes and pathways in immune and pathogenic phenomena. We aim to capitalize on our expertise in a range of animal models of immunity and disease (covering in vivo models for the breakdown of tolerance, chronic neuroinflammation and demyelination, chronic arthritis, inflammatory bowel disease and systemic inflammation and autoimmunity). Using this unique collection of disease models, and by preparing mice with conditionally inactivated genes for cytokines, receptors and intracellular signaling pathways, we will be searching for specific cells, genes and pathways with dominant involvement in disease pathogenesis. The results of these experiments are expected to bring forward the state of the art in the search for detailed mechanisms in chronic disease pathogenesis and to provide new and more effective diagnostic and therapeutic targets.

2. To develop more accurate animal models for chronic immunopathologies and autoimmunity. In their large majority, current animal models of disease do not provide information as to the specific cells, and inter-or intra-cellular signals involved in the development of the phenotype. By addressing these questions using conditional or tissue specific gene targeting in several models of chronic immunopathologies and autoimmunity (see above), we aim to better define the molecular and cellular mechanisms involved in disease induction and progression in vivo, and, therefore, to provide more accurate models of disease. These advanced genetic systems should prove extremely useful as accurate screening targets for the identification and validation of novel drugs.

3. To discover new genes and pathways in immunity and disease. The ‘genome project’ is resulting in rapid advances in technology and in the generation of enormous amounts of sequence and gene expression data. The implications of these technical developments and their implementation for the purpose of therapeutic discovery and development is vast. Using commercial and home-produced cDNA microarray technology, we aim to discover novel cell-specific genes expressed in dendritic cells, activated synoviocytes, endothelial, epithelial and microglia cells, derived from specific disease models or immunologically disturbed hosts. Generation of such expression databases should form the basis for a more global understanding of gene expression and gene function in chronic disease.

Most importantly we wish to capitalize on our existing expertise in the field of ENU-induced random mutagenesis for the establishment of sensitized screens in which immunological disease modifier loci will be identified through random mutagenesis of existing animal models of immunological diseases. With forward genetics approaches we intent to discover novel therapeutic targets and pathways in arthritis and IBD by using the TNFΔARE mouse model and selecting TNFΔARE mutagenized mice with disease neutralized phenotypes. In subsequent phases, and based on advances and information that will become available from the ‘mouse genome project’ and the large-scale ENU mutagenesis collaborators, we will be able to define the specific mutated genes which are responsible for the therapeutic effects in our disease models. It can be assumed that players identified in such sensitized screens are prime candidates for pharmacological intervention. Our experience of establishing ENU sensitized screens can be used as a paradigm for other researchers in Greece or abroad for the application of similar approaches using other animal models of immunological disorders.

4. To evaluate the function of newly discovered genes in modeled genomes. Understanding the function of new genes requires a large set of different techniques, giving information on the gene, its transcript, its expression pattern and level, its functional relevance to the studied phenomena, and, last but not least, its impact on the in vivo phenotype. Our research will address the functional relevance of newly identified genes, first in vitro, via antibody / antagonist / antisense /dominant negative / or RNAi-based neutralisation of activity and involvement in intra- or intercellular signaling, homing, chemotaxis, cytotoxic activity, proliferation, differentiation, apoptosis etc. Following this step, the most relevant genes for chronic immunopathologies and immunity will be conditionally inactivated in the mouse genome as a means to derive firm evidence on their in vivo function.

5. To disclose new diagnostic markers and therapeutic targets. The results of the proposed studies carry a high degree of innovation and advance the state of the art in the research for detailed mechanisms in chronic disease pathogenesis. The use of a wide range of chronic disease models and the investigation of the involvement of several known or novel genes, pathways and cells with putative dominant roles in disease initiation, progression and chronicity, should allow more accurate knowledge of pathogenic mechanisms, and readily provide new diagnostic markers and more effective therapeutic targets.

Expected achievements and deliverables of the research we undertake in our lab are likely to also help elucidate mechanisms in immune processes or groups of diseases other than those studied here (e.g. transplantation, cancer, AIDS, neurodegenerative diseases, etc), and will therefore be of broad scientific and socio-economic value.