Cell interactions with the extracellular matrix

Abstract

IntroductionThe idea of a special issue on cell interactions with theextracellular matrix (ECM) is a result of the increasingawareness about the integral functions of the ECM invirtually all dynamic processes of development, mainte-nance, reconstruction and disease. The purpose of thisspecial issue is not to present a comprehensive overview ofall macromolecules that form the ECM and their interact-ing cellular receptors, as many excellent reviews andmonographs have been published recently on this topic(Myllyharju and Kivirikko 2004;Kadleretal.2007;Batemanetal.2009). Rather, it is the guest editors´ objectiveto present recent advances in ECM-cell interactions as seenfrom the perspective of dynamic cell performances duringdevelopment and in various disease states.The importance of ECM biology and pathology isimmediately recognised when thinking of the extent to whichECM molecules and their cellular receptors are involved indiseases. A wide range of diseases, initially not understoodunder the aspect of ECM pathology, existsin which the ECMcontributes considerably to onset and progression. Amongthese are all fibrotic diseases of the skin, liver, lung andkidney, some skeletal, muscular and neurodegenerativediseases and diseases in clinical fields, such as pulmology,cardiology, and ophthalmology. Only the comprehensiveanalysis of ECM genes has provided insights into genotype-phenotype relationships of hereditary connective tissuediseases such as osteogenesis imperfecta, numerous skeletaldisplasias, Ehlers-Danlos syndrome, Marfan syndrome andepidermolysis bullosa. Failures in wound healing, fracturerepair and degenerative autoimmune diseases critically in-volve disregulation of ECM metabolism or autoimmunereactions against matrix macromolecules.In addition to diseases with a crucial involvement of theECM, physiological processes, such as stem cell differen-tiation, which have previously not been seen in the contextof ECM involvement, are now increasingly acknowledgedas being crucially dependent on the composition of theECM and the stromal cells.A brief overview of articles in this special issueThe series of articles on cell interactions with the ECMbegins with a presentation by Bruckner (2009) of thehierarchical organisation of the ECM and the assembly ofmacromolecules into insoluble suprastructural elements.Such suprastructural elements can be fibrils, microfibrilsor networks, which, in turn, are assembled into regionaltissue structures, such as fibres or basement membranes.Interestingly, most, if not all ECM suprastructures are co-