The platelet proteasome and immunoproteasome are stable in buffy-coat derived platelet concentrates for up to 7 days.

Objectives: Characterization of the proteasome and its stability in buffy-coat derived platelet concentrates (PCs) during storage.

Background: The proteasome plays a key role in cell homeostasis by processing misfolded or abnormal proteins and regulating the levels and activities of a high number of proteins contributing to cell cycle, survival, and proliferation. Controversial data exist, whether inhibition of the proteasome affects platelet function.

Structure and function of the ubiquitin-proteasome system in platelets.

Platelets are small anucleate blood cells with a life span of 7 to 10 days. They are main regulators of hemostasis. Balanced platelet activity is crucial to prevent bleeding or occlusive thrombus formation.