The lifespan of circulating endogenous platelets is determined by a combination of random platelet removal and a nonrandom aging mechanism after which senescent platelets are removed by the reticuloendothelial system. At least a portion of platelet senescence is regulated by an intrinsic apoptotic pathway that acts as an internal timer. Platelets contain members of the antiapoptotic Bcl-2 famil...

Platelet membrane glycoprotein (GP) Ib contains receptors for von Willebrand factor and thrombin. Its proteolytic fragment, glycocalicin, circulates in normal plasma. In this study, storage of platelet concentrates for 5 d resulted in a 221% increase in plasma glycocalicin (1.3 times the total amount of glycocalicin present on the surface of all platelets), an 8% overall increase in platelet su...

This study was designed to examine the effects of standard 22°C platelet storage and platelet cryopreservation ;pn surface glycoproteins, light scattering properties and surface-bound factor V using flow cytometry. Single donor platelet units were collected in ACD (formula A) using a^Haemonetics Mobile Collection System. The units were either liquid-preserved at 22°C with rotation for up to 7 d...

Concerns over bacterial proliferation in room temperature–stored platelet concentrates prompted the US Food and Drug Administration on June 02 1986 to issue a memorandum to blood establishments directing a reduction in the allowable storage time of platelet concentrates from 7 to 5 days. In this memorandum, the FDA called attention to several cases of fatal post-transfusion sepsis from platelet...

High quality means good fitness for the intended use. Research activity regarding quality measures for platelet transfusions has focused on platelet storage and platelet storage lesion. Thus, platelet quality is judged from the manufacturer's point of view and regulated to ensure consistency and stability of the manufacturing process. Assuming that fresh product is always superior to aged produ...

In an ongoing study of the changes that occur in platelet concentrates during storage, we investigated two 28-26-Kd proteins designated SP-1 and SP-2, respectively, which increase markedly during blood-bank storage of platelet concentrates at room temperature. Formation of SP-1 and SP-2 was inhibited by storage at 4 degrees C as well as by treatment of the concentrates with leupeptin, N-ethylma...

Proteases, and specifically metalloproteinases, have been linked to the loss of platelet function during storage before transfusion, but the underlying mechanisms remain unknown. We used a dedicated N-terminomics technique, iTRAQ terminal amine isotopic labeling of substrates (TAILS), to characterize the human platelet N-terminome, proteome, and posttranslational modifications throughout platel...

A study has been undertaken to determine the rate at which stored platelets lose their ability to respond to stimuli and to establish whether this decrease in function could be ascribed to the storage-induced proteolysis of prominent platelet proteins observed by others. Platelet concentrates were stored at 4 degrees C and 25 degrees C for up to 14 days, and their ability to secrete and aggrega...

To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control pl...

BACKGROUND Tissue factor (TF), the main activator of blood coagulation, is expressed on platelet surface and, together with procoagulant phospholipids, contributes to the global coagulation potential of these blood components. The present study evaluated, for the first time, the expression of TF on platelet surface during preparation and storage of platelet concentrates (PC) for transfusional u...