Innovative in vitro and ex vivo models in multidisciplinary European lameness research

Research of the past 10 years has become more and more interdisciplinary employing modem methods of epidemiology, cellular biology and molecular biology. New hypotheses have evolved to demonstrate possible links between systemic problems and local damage in the claw. However, understanding the physiopathology, especially the links between a systemic problem and the local alterations in the claw tissue is still limited. In vitro models have gained more importance in studying the physiopathology of claw diseases because they enable studies on these links and tissue mechanisms. The development and experimental application of novel in vitro and ex vivo models was a major task of the EU framework 5 project Lamecow (http://www.abdn.ac.uk/lamecow). Parts of the outcome of this project are different cell culture systems including three dimensional organotypic culture systems. In addition a novel ex vivo model, the isolated haemoperfused distal cow limb model (Wustenberg 2004), has been developed and used for experiments. The innovative in vitro models enable studies under standardised conditions in cell clines, complex organotypic cultures and finally testing in the isolated limb perfusion model under conditions as close as possible in a model to the in vivo situation. Individual local regulatory cascades can be studied in vitro and hypotheses basing on this in vitro work can then be tested on the organ level in the ex vivo haemoperfused limb model. This paper reports on the development and application of innovative organotypic in vitro systems and a novel ex vivo model, the isolated haernoperfused distal cow limb model.