title: Use of a cytokine-release assay to demonstrate loss of platelet secretory capacity during blood bank processing and storage.
abstract: BACKGROUND
  The extent to which changes in secretory function contribute to the storage lesion of platelets (PLTs) prepared for transfusion is not well described.
  
  
  OBJECTIVE
  To develop a cytokine-release assay for the assessment of PLT secretory capacity during the preparation and storage of PLTs.
  
  
  METHODS
  Small volumes of PLT-rich plasma and PLT concentrate (PC) were prepared from whole blood (WB; N = 4 donors). Aliquots of WB, PLT-rich plasma, and PC were treated with 20 μM adenosine diphosphate or saline (control). Samples of WB-derived PCs obtained from a regional blood center were similarly stimulated at various storage times (N = 10 units). Plasma levels of RANTES (chemokine ligand 5; regulated on activation, normal T cell expressed and secreted) and PLT aggregation were measured following agonist addition.
  
  
  RESULTS
  Adenosine diphosphate stimulated RANTES release from PLTs in fresh WB on average by 4.1-fold (P < .001), in PLT-rich plasma by 4.7-fold (P = .002), and in PC by 1.3-fold (P < .001). For blood center PCs, adenosine diphosphate failed to stimulate RANTES release at day 2 of storage or later (P ≥ .31). Baseline RANTES levels in the plasma/supernatant increased 660% during PC preparation (P = .02) and an additional 30% during subsequent storage (P < .001). Mean PLT aggregation decreased during processing from WB (95.6%) to PC (60.5%; P = .04). For blood center PCs, mean PLT aggregation decreased substantially from days 2 (41.0%) to 7 (2.3%; P < .001).
  
  
  CONCLUSIONS
  A cytokine-release assay revealed a diminution in PLT secretory capacity during PC processing and storage, with complete elimination by day 2 of storage. Loss of PLT aggregability occurred more slowly. The cytokine-release assay may be a useful endpoint for optimizing PLT preparation and storage.
authors.affiliation: From Pathology and Laboratory Medicine Service, VA Connecticut Healthcare System, West Haven; and the Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Tormey
authors.forename: Gary
authors.initials: G
authors.lastname: Stack
mesh_terms: D001771:Blood Banks; D001792:Blood Platelets / Q000378:metabolism*; D001793:Blood Preservation; D001800:Blood Specimen Collection; D018946:Chemokine CCL5 / Q000097:blood / Q000378:metabolism; D016207:Cytokines / Q000097:blood* / Q000378:metabolism; D006801:Humans; D010974:Platelet Aggregation; D010979:Platelet Function Tests; D017713:Platelet Transfusion; D013997:Time Factors
chemical_list: C483024:CCL5 protein, human; D018946:Chemokine CCL5; D016207:Cytokines