In vivo recovery and survival of apheresis and whole blood-derived platelets: a paired comparison in healthy volunteers

BACKGROUND: Methods of platelet preparation may alter the recovery and survival characteristics of platelets following transfusion. As suggested by a recent clinical trial, platelet recovery may be better preserved with apheresis platelet preparations than with platelets prepared from whole blood by the platelet-rich plasma (PRP) method. STUDY DESIGN AND METHODS: In vivo platelet recovery and survival of autologous leukoreduced (LR) apheresis platelets and autologous filter-LR PRP platelets were compared in 22 healthy volunteers using a paired crossover design. On the same day, each participant gave one apheresis platelet donation and one whole blood donation from which platelets were recovered from the PRP. The sequence of donations was randomly assigned for each participant. Following 5 days of storage and bacterial screening, a sample from each platelet product was labeled with either (51)chromium or (111)indium (randomly assigned) and both samples were simultaneously re-infused into the original donor. Recovery and gamma-function platelet survival were calculated for each platelet product using the multiple hit mathematical model. RESULTS: Five day stored LR-apheresis platelets had 18.8 percent better recovery, and 32.9 percent longer gamma-survival than filter-LR PRP platelets. Stored apheresis platelets had lower p-selectin expression and higher morphology scores than stored PRP platelets. CONCLUSIONS: Filter-LR PRP platelet preparation appears to adversely affect platelet recovery and survival characteristics. The reasons for this effect are not clear. These results may not apply to all apheresis and PRP methods of platelet preparation.