The project deals with the development of procedures to enrich and isolate defined cell types from blood for daignostic purposes. The focus of the project is on the development of a method to enrich circulating tumor cells from a large blood volume using specific adsorbents. The two main areas of work are (1) the development and characterization of adsorbents for the specific binding of cells (polymers functionalized with antibodies against tumor surface antigens), and (2) the development of technologies to pre-enrich circulating tumor cells (leukpaheresis and elutriation).