title: Pathogen inactivation of double-dose buffy-coat platelet concentrates photochemically treated with amotosalen and UVA light: preservation of in vitro function.
abstract: BACKGROUND
  The INTERCEPT Blood System for Platelets (PLT) utilizes amotosalen (S-59) in combination with ultraviolet A (UVA) light to inactivate viruses, bacteria, protozoa and leucocytes that may contaminate PLT concentrates. However, limited data are available on the quality of INTERCEPT-treated double-dose (DD) buffy-coat (BC) PLT units allowing a single treatment procedure to produce two pathogen-inactivated PLT units for transfusion.
  
  
  METHODS
  The objective of this study was to evaluate potential in vitro effects of the INTERCEPT treatment on pools of 7 BCs as compared to untreated units. Functional, phenotypic and mitochondrial properties of DD BC PLTs during storage over 7 days were studied.
  
  
  RESULTS
  For some parameters measured, small yet significant differences were observed including PLT count (P < 0·05), pH, pCO2 and glucose concentration. Throughout storage, no significant differences were observed in ATP levels, ESC, HSR reactivity and CD62P expression. Similarly, no differences were observed in the expression of PAC-1, CD42b and PECAM-1 at any time-points. The mitochondrial membrane potential (MMP) determined by JC-1-labelling was well maintained until day 7 in all treated and untreated units (>90%). The release of sCD40L increased over time (P < 0·01) in all units but without any significant differences between treated and untreated PLTs.
  
  
  CONCLUSIONS
  Our data demonstrate that photochemical pathogen inactivation of DD-BC PLT concentrates with the INTERCEPT Blood System had no influence on the PLT in vitro quality over the 7 day of storage. However, whether in vivo efficacy of INTERCEPT-treated PLTs is affected may require clinical evaluation.
authors.affiliation: Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Sandgren
authors.forename: B
authors.initials: B
authors.lastname: Diedrich
mesh_terms: D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology / Q000528:radiation effects; D058731:Blood Safety / Q000379:methods*; D011564:Furocoumarins / Q000494:pharmacology; D006801:Humans; D017319:Photosensitizing Agents / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D011564:Furocoumarins; D017319:Photosensitizing Agents; C118577:amotosalen
keywords: UVA; amotosalen; pathogen inactivation; platelets