Inhibition of metalloproteinase activity prevents cleavage of GPIbα on CCCP-treated human platelets. Washed human platelets were treated for 8 hours at 37°C with DMSO, CCCP, or GM6001/CCCP. Cells were stained with monoclonal antibodies against GPIbα and GPIX and analyzed by flow cytometry. Results are representative of 5 experiments.