Determination of thromboxane formation, soluble CD40L release and thrombopoietin clearance in apheresis platelet concentrates

Abstract

All deleterious changes in platelet morphology, structure and function that occur in platelet concentrates (PC) during storage are titled as the 'platelet storage lesion'. No single in vitro test currently available is sufficient in assessing these changes of platelet quality. The release of soluble CD40 Ligand (sCD40L), the formation of thromboxane (TXB2) and the thrombopoietin (TPO) clearance reflect different aspects of platelet metabolism and activitiy, and were used to examine platelet quality in apheresis platelet products. At days 1, 3 and 5, in single-donor apheresis platelet products (n = 10) under routine storage conditions, sCD40L (measured by ELISA) and TXB2 (measured by RIA) were determined after platelet stimulation (recalcification and clot formation). TPO (measured by ELISA) was determined after an incubation time of 5 h at 37°C with platelet-rich plasma (adjusted initial TPO concentration of about 500 pg/mL). Results were related to a therapeutic unit (TU = 2 × 10(11) platelets). Immediately after platelet preparation, sCD40L release was 41 ± 7.6 ng/TU, TXB2 formation 1688 ± 374 ng/TU and TPO clearance 1.22 ± 0.32 ng/h/TU. At days 1, 3 and 5, sCD40L was reduced to 89 ± 7%, 71 ± 12% and 57 ± 9%, TXB2 release to 91 ± 6%, 74 ± 12% and 58 ± 9% and TPO clearance to 90 ± 15%, 84 ± 5% and 79 ± 10% of the respective control values. In conclusion, in single-donor apheresis PC, sCD40L release and TXB2 formation as well as TPO clearance by the platelets were dependent on storage duration and reduced to about 60% to 80% of the respective control values after a storage period for 5 days. These findings are in line with literature data, indicating that a loss of platelet functionality of about 30% will occur after 5 days of storage.

Changes in platelet morphology and function during 24 hours of storage

“…CD62P + PMPs [17,43]. These results are in good agreement with the above described morphological data and reports concerning the PMP generation of platelets in platelet concentrates, the so-called platelet storage lesion [8,39,45]. Moreover, our data reveal a progressively reduced number of platelets that can be activated by ADP (CD62P, CD42a) in the PRP sample.…”

“…Among others, a prolonged storage time can have a strong influence on the results of platelet interactions with implant materials. Currently, only scarce data are available about the influence of the storage time on platelet aggregation -a process named "platelet storage lesion" [26,45] -and most of those studies were carried out only after short storage times of up to two hours [19,20,22,42]. In the present study, the association between storage time and integrity and function of platelets was assessed over a time period of 24 hours.…”

Not all (N)SAID and done: Effects of nonsteroidal anti‐inflammatory drugs and paracetamol intake on platelets

“…When recalcified and clotted, platelets stored for 3 days and longer showed reduced TxA 2 formation, indicating decreased COX‐1 activity. At days 3 and 5, TxA 2 accumulates in unstimulated stored platelets . Furthermore, when platelets stored for 3 days are stimulated with collagen, TxA 2 formation is reduced in the platelet supernatant by 20% to 30% .…”

Use of a Cytokine-Release Assay to Demonstrate Loss of Platelet Secretory Capacity During Blood Bank Processing and Storage

“…9,10 However, few studies have examined the integrity of other cellular functions of PLT preparations, such as secretory capacity and the granule release reaction. [11][12][13] Because maintenance of PLT secretory capacity may be important, as noted above, particularly for immunosuppressed or anticoagulated patients, it is potentially useful to examine the impact of current blood bank preparation and storage conditions on this aspect of PLT function.…”