Transfusion of platelets is used either prophylactic to reduce the risk of clinical threatening bleedings or therapeutic to treat acute life-threatening thrombocytopathic-relevant bleedings (e.g. thrombocytopenic traumatic injuries, hematopoietic stem cell transplantation, chemotherapy). Activation and enhancement of platelet reactivity is the key step during hemostasis. After the first activation at the point of blood vessel trauma the platelets then aggregate and form a stable thrombus. This process is irreversible; the platelets are removed by macrophages during the subsequent following tissue regeneration.
In general, platelet concentrates are stored at +22°C ± 2° C in gas-permeable, sterile plastic bags; the maximum shelf life is 5 days. Anticoagulants (Heparin, Citrate) are used to prevent activation and aggregation of platelets before transfusion. Lethal sepsis in the course of platelet transfusion due to bacterial contamination can occur especially when using stored platelets at the end of their shelf life.

Aim of this project is to extend the shelf life of platelet concentrates and to characterize their actual state via real-time analysis. Utilizing high-resolution microscopy techniques on different biochemical surfaces allows monitoring activation-induced changes from the cellular - down to the molecular - level. Physico-chemical parameters during storage will be characterized. Moreover, the project is aimed to classify the interaction reactivity of (transfused) platelets following storage with the cells of the individual receiver.