title: Plasmin activity and complement activation during storage of citrated platelet concentrates.
abstract: Platelet concentrates were studied for evidence of plasmin activity and complement activation during a 7-to-10-day storage period. When measured by an amidolytic activity assay, plasmin reached a level of 845 +/- 540 nkats/L on day 7 (n = 9). Fibrin(ogen) degradation product (FDP) levels became markedly elevated on the tenth day of storage, rising to 45 +/- 22 micrograms/ml (n = 5). Antiplasmin levels decreased in platelet concentrates by 18% +/- 6% (n = 5) over 7 days, but there was no significant decrease in stored platelet-poor plasma (-1.7%, n = 5, p = 0.5). The amount of plasminogen in platelet concentrate converted to plasmin was estimated to be less than 3% by assay of total plasminogen. Supernatant plasma from stored platelet concentrates was examined for the presence of the complement activation peptides C3a and C5a. From day 0 to day 10 of storage, mean C3a levels rose from 327 ng/ml to 6690 ng/ml. An equivalent increase in C3a levels, from 336 ng/ml at day 0 to 6866 ng/ml at day 10, was also observed in stored platelet-poor plasma. C5a was not detected (less than 10 ng/ml) at any point during the storage period; however, we noted a small decrease of borderline significance (p = 0.04) in total C5 from day 0 (117 micrograms/ml) to day 10 (108 micrograms/ml). Only trace amounts of C3 fragments were found on stored platelets, and there was no evidence of the membrane attack complex. These findings indicate the presence of plasmin activity and conversion of C3 during storage of platelet concentrates.
authors.affiliation: Department of Clinical Pathology and Diagnostic Medicine, East Carolina University School of Medicine, Greenville, NC 27858.
authors.forename: A P
authors.initials: AP
authors.lastname: Bode
authors.forename: D T
authors.initials: DT
authors.lastname: Miller
authors.forename: S L
authors.initials: SL
authors.lastname: Newman
authors.forename: W J
authors.initials: WJ
authors.lastname: Castellani
authors.forename: H T
authors.initials: HT
authors.lastname: Norris
mesh_terms: D001792:Blood Platelets / Q000032:analysis*; D001793:Blood Preservation; D003167:Complement Activation; D003176:Complement C3 / Q000032:analysis / Q000096:biosynthesis; D015926:Complement C3a; D003182:Complement C5 / Q000096:biosynthesis; D015936:Complement C5a; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005341:Fibrinolysin / Q000032:analysis*; D006801:Humans; D010958:Plasminogen / Q000378:metabolism; D000979:alpha-2-Antiplasmin / Q000097:blood
chemical_list: D003176:Complement C3; D003182:Complement C5; D005338:Fibrin Fibrinogen Degradation Products; D000979:alpha-2-Antiplasmin; D015926:Complement C3a; D015936:Complement C5a; D010958:Plasminogen; D005341:Fibrinolysin