title: Platelet transfusion alters CD40L blood level and release capacity in patients suffering from thrombocytopenia.
abstract: BACKGROUND
  Platelet (PLT)-derived cytokines, such as soluble CD40 ligand (sCD40L), play an important role in the development of adverse transfusion reactions associated with the administration of PLT products. In this study, we determined sCD40L concentration and release capacity in patients with thrombocytopenia before and after receiving a PLT transfusion.
  
  
  METHODS
  The study included 12 patients suffering from chemotherapy-induced thrombocytopenia. sCD40L levels and release capacity were measured in plasma samples of the patients before and after PLT administration as well as in the respective plateletpheresis concentrates by enzyme-linked immunosorbent assay. Sixteen healthy blood donors served as a control group.
  
  
  RESULTS
  In PLT concentrates, elevated sCD40L levels (2567±134 pg/mL) were observed in comparison to plasma sCD40L levels in controls (238.4±35.3 pg/mL). sCD40L plasma concentration of patients with thrombocytopenia was significantly reduced (86.3±16.7 pg/mL) before transfusion and increased to nearly normal levels (204.4±24.8 pg/mL) after PLT administration. In parallel, the sCD40L release capacity per PLT showed no significant difference between controls and patients with thrombocytopenia before transfusion (33.3±2.6 and 29.3±4.6 ag/PLT, respectively) but was significantly reduced after PLT transfusion (22.4±2.7 compared to 29.3±4.6 ag/PLT).
  
  
  CONCLUSIONS
  In patients with thrombocytopenia, sCD40L levels were clearly influenced by PLT transfusions: PLT administration led to a normalization of sCD40L plasma concentration. Nevertheless, adverse transfusion reactions did not occur in these patients. The sCD40L release capacity was enhanced by PLT administration dependent on the increase in the amount of PLT count.
authors.affiliation: Institute for Transplantation Diagnostics and Cell Therapeutics, Heinrich-Heine University Medical Center Düsseldorf, Düsseldorf, Germany. folker.wenzel@gmx.de
authors.forename: Folker
authors.initials: F
authors.lastname: Wenzel
authors.forename: Wiebke
authors.initials: W
authors.lastname: Günther
authors.forename: Anja
authors.initials: A
authors.lastname: Baertl
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gruber
authors.forename: Rüdiger Volker
authors.initials: RV
authors.lastname: Sorg
authors.forename: Rainer
authors.initials: R
authors.lastname: Haas
authors.forename: Günther
authors.initials: G
authors.lastname: Giers
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001782:Blood Donors; D023201:CD40 Ligand / Q000097:blood* / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy; D010976:Platelet Count; D017713:Platelet Transfusion / Q000009:adverse effects*; D010983:Plateletpheresis; D013921:Thrombocytopenia / Q000097:blood* / Q000139:chemically induced / Q000378:metabolism*
chemical_list: D023201:CD40 Ligand