Dr. Miles studies how interactions of proteolytic systems (specifically the plasminogen activation system) with cell surfaces modulate cellular function and how cells modulate protease systems via positive feedback mechanisms. Recently, using a proteomics approach and a monocyte progenitor cell line, Dr. Miles identified a novel protein, the plasminogen receptor, Plg-RKT, which has unique properties including a transmembrane topology with a carboxyl terminal lysine exposed on the cell surface in an orientation to bind plasminogen and stimulate plasminogen activation and is colocalized with and physically associates with the urokinase type plasminogen activator receptor (uPAR). Ongoing research employs newly developed reagents including specific function-blocking anti-Plg-RKT antibodies, region specific peptide mimetics, and Plg-RKT protein expression systems to address the role of this new plasminogen receptor in inflammation and cancer progression.