Expression of plasminogen receptors on C6 glioma cells

Plasminogen activators (PAs) play an important role in normal and neoplastic neuromorphogenesis in the central nervous system. Proper function of proteinases such as PA may require focusing of activity on a cellular level. In this study, we demonstrate that highly purified plasminogen binds to receptors on rat C6 glioma cells in culture. Specific binding is reversible and saturable at 4 degrees C. The Kd is 1.95 +/- 0.31 microM and the Bmax is 3.6 x 10(6) molecules/cell. At 37 degrees C, there is no evidence for ligand digestion or internalization. Plasminogen receptors may concentrate potential proteinase near membranes of glia during normal and neoplastic development in the central nervous system.