title: Prolonged holding of whole blood at 22 degrees C does not increase activation in platelet concentrates.
abstract: OBJECTIVE
  Platelets prepared after holding of whole blood overnight at 22 degrees C have a well-preserved metabolism. However, the possibility that such prolonged incubation with active granulocytes may increase platelet activation has not been fully tested.
  
  
  METHODS
  We investigated this possibility by flow cytometric analysis of membrane glycoproteins (GPs) Ib and IIb/IIIa and the activation markers CD62P and CD63 in platelet concentrates (PCs) prepared from whole blood that was held for either 6 h without cooling plates (n = 20) or for 24 h on cooling plates of 1,4-butanediol (n = 20). PCs were prepared by the platelet-rich plasma method and analyzed on the second storage day.
  
  
  RESULTS
  Platelet yield and aggregation response to ristocetin, collagen and epinephrine + ADP were similar in both types of PCs, as was the mean fluorescence intensity for GPs Ib and IIb/IIIa. PCs prepared by the overnight-hold method did not differ from those obtained 6 h after collection in the percentage of platelets expressing CD62P (12.3 +/- 6.2% vs. 14.1 +/- 4.0%; p > 0.1) or CD63 (9.8 +/- 6.4% vs. 8.8 +/- 3.6%; p > 0.1).
  
  
  CONCLUSIONS
  Prolonged holding of whole blood at 22 degrees C prior to component preparation does not increase the level of platelet activation.
authors.affiliation: Service of Hemotherapy and Hemostasis, Hospital Clínico, Barcelona, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Sanz
authors.forename: A
authors.initials: A
authors.lastname: Pereira
authors.forename: A I
authors.initials: AI
authors.lastname: Faúndez
authors.forename: A
authors.initials: A
authors.lastname: Ordinas
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D015703:Antigens, CD / Q000032:analysis; D015415:Biomarkers; D001793:Blood Preservation / Q000379:methods*; D003094:Collagen / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005434:Flow Cytometry; D006098:Granulocytes / Q000502:physiology; D006801:Humans; D019007:P-Selectin / Q000097:blood; D015539:Platelet Activation; D010974:Platelet Aggregation / Q000187:drug effects; D010980:Platelet Membrane Glycoproteins / Q000032:analysis; D012310:Ristocetin / Q000494:pharmacology; D013696:Temperature; D060149:Tetraspanin 30; D013997:Time Factors
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; C554586:CD63 protein, human; D019007:P-Selectin; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30; D012310:Ristocetin; D000244:Adenosine Diphosphate; D003094:Collagen; D004837:Epinephrine