title: The association of the Thr715Pro P-selectin genotype with levels of P-selectin in platelet concentrates.
abstract: OBJECTIVE
  P-selectin is stored in the alpha granules of platelets and in the Weibel Palade bodies of endothelial cells; upon activation, it is translocated to the cell surface and released into the plasma in soluble form. One variant of the P-selectin gene, the Thr715Pro polymorphism, is strongly associated with the plasma levels of soluble P-selectin. In platelet concentrates soluble P-selectin can be regarded mainly platelet derived.
  
  
  METHODS
  The relation of the genotype with soluble P-selectin, platelet expressed P-selectin and the sum of all forms of P-selectin - comprising soluble P-selectin, platelet surface P-selectin and P-selectin from the alpha granules - was assessed in fresh whole blood and in apheresis platelets suspended in 35% plasma/65% SSP+ obtained from 89 platelet donors.
  
  
  RESULTS
  Levels of total P-selectin were genotype associated (P = 0·025); likewise, in fresh whole blood there was an association of soluble P-selectin with genotype (P = 0·02). In platelets suspended in additive solution, however, levels of the storage-associated or TRAP-6 agonist induced increase of platelets' P-selectin were not associated with the genotype. A correlation between levels of soluble P-selectin and surface expression of P-selectin was observed on day 3 of storage in Thr715Thr individuals (P < 0·0001), but not in heterozygotes (Thr715Pro, P = 0·2).
  
  
  CONCLUSIONS
  The donors' genotype has only little influence on levels of soluble P-selectin in apheresis platelets suspended in 35% plasma/65% SSP+.
authors: Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria.
authors: P
authors: P
authors: Jilma-Stohlawetz
authors: C
authors: C
authors: Mannhalter
authors: A
authors: A
authors: Kaider
authors: T
authors: T
authors: Waidacher
authors: B
authors: B
authors: Jilma
authors: S
authors: S
authors: Panzer
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D019007:P-Selectin / Q000097:blood / Q000235:genetics*; D010446:Peptide Fragments / Q000819:agonists; D010983:Plateletpheresis; D020641:Polymorphism, Single Nucleotide
chemical_list: D019007:P-Selectin; D010446:Peptide Fragments; C082835:thrombin receptor peptide (42-47)
keywords: P-selectin; Thr715Pro polymorphism; platelets; soluble P-selectin