CD47 immobilization prevents the attachment of blood leukocytes to stainless steel surfaces. The Chandler Loop apparatus was used, as detailed in Materials and Methods, to expose citrate-treated whole human blood to the luminal surface of unmodified steel inserts or BSA, recCD47, or pepCD47-modified steel inserts that were placed into medical grade PVC tube conduits. DAPI staining of adherent cells were visualized, and randomly selected 200X fields were counted. Results show that immobilization of CD47 significantly reduced blood cell adhesion to the steel surfaces. Results represent the average and standard deviation of the mean of nine individual fields (P < 0.0001).