The group is studying differentiation of stem cells in vitro and is mainly interested in chondrogenic and nephrogenic differentiation. Embryonic stem (ES) cells are undifferentiated and pluripotent and have the capacity to differentiate int cell types of all three primary germ layers and into germ cells. In vivo, they can be used for gene-targeting to establish genetically altered mice. In vitro, they differentiate spontaneously into many cell types when cultivated as embryoid bodies (EBs). This process closely recapitulates embryogenesis.

The model system of ES cell differentiation in vitro enables one to study the influence of exogeneous factors on differentiation such as growth factors and signaling molecules. Furthermore, by differentiation of 'gene targeted' or 'transgenic' ES cells the function of specific genes during differentiation can be investigated. Induced pluripotent stem (iPS) cells derived from patients with genetically caused disease such as Osteogenesis imperfecta (OI) or polycystic kidney disease (PKD) are currently in the focus of the group for disease modeling in vitro. In addition, adult stem cells have been isolated and characterized from different tissues. The role of stromal cells during kidney injury is analyzed using an animal model system of renal ischemia.