title: In vitro effects on platelets irradiated with short-wave ultraviolet light without any additional photoactive reagent using the THERAFLEX UV-Platelets method.
abstract: BACKGROUND
  A novel short-wave ultraviolet light (UVC) pathogen reduction technology (THERAFLEX UV-Platelets; MacoPharma, Mouvaux, France) without the need of any additional photoactive reagent has recently been evaluated for various bacteria and virus infectivity assays. The use of UVC alone has on the one hand been shown to reduce pathogens but may, on the other hand, have some impact on the platelet (PLT) quality. The purpose of this study was to determine the potential effects on PLT quality of pathogen inactivation treatment using the novel UVC method for PLT concentrates.
  
  
  METHODS
  Buffy-coat-derived PLTs suspended in SSP+ were irradiated with UVC light in plastic bags (MacoPharma) made of ethyl vinyl acetate, considered to be highly permeable to UVC light. The UVC-treated (test, n=8) as well as the untreated (reference, n=8) PLT units were stored in PLT storage bags composed of n-butyryl, tri n-hexyl citrate-plasticized polyvinyl chloride (MacoPharma) on a flat bed agitator for in vitro testing during 7 days of storage.
  
  
  RESULTS
  No significant difference in PLT counts and lactate dehydrogenase between the groups was detected. During storage, glucose decreased more and lactate increased more in the test units. Statistically significant differences were found for glucose (P<0·01) and lactate (P<0·05) on day 7. ATP levels were higher (P<0·01 from day 5) in the reference units. With exception of day 7 (P<0·01 reference vs. test), hypotonic shock response reactivity was not different between groups. Extent of shape change was lower (P<0·01), and CD62P (P<0·05 day 5) was higher in the test units. CD42b and CD41/61 showed similar trends throughout storage, without any significant difference between the units. pH was maintained at >6·8 (day 7) and swirling remained at the highest level (score = 2) for all units throughout storage.
  
  
  CONCLUSIONS
  Our results suggest that irradiation with UVC light has a slight impact on PLT in vitro quality and appears to be insignificant with regard to current in vitro standards.
authors.affiliation: Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden. per.sandgren@karolinska.se
authors.forename: P
authors.initials: P
authors.lastname: Sandgren
authors.forename: F
authors.initials: F
authors.lastname: Tolksdorf
authors.forename: W G
authors.initials: WG
authors.lastname: Struff
authors.forename: H
authors.initials: H
authors.lastname: Gulliksson
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism* / Q000528:radiation effects; D001419:Bacteria / Q000254:growth & development / Q000528:radiation effects; D001792:Blood Platelets / Q000378:metabolism* / Q000382:microbiology / Q000528:radiation effects*; D001793:Blood Preservation / Q000379:methods*; D005947:Glucose / Q000378:metabolism* / Q000528:radiation effects; D006801:Humans; D039661:Integrin beta3 / Q000378:metabolism / Q000528:radiation effects; D007770:L-Lactate Dehydrogenase / Q000378:metabolism / Q000528:radiation effects; D019344:Lactic Acid / Q000378:metabolism* / Q000528:radiation effects; D019007:P-Selectin / Q000378:metabolism / Q000528:radiation effects; D010976:Platelet Count; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000378:metabolism / Q000528:radiation effects; D040201:Platelet Membrane Glycoprotein IIb / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D039661:Integrin beta3; D019007:P-Selectin; D019038:Platelet Glycoprotein GPIb-IX Complex; D040201:Platelet Membrane Glycoprotein IIb; D019344:Lactic Acid; D000255:Adenosine Triphosphate; D007770:L-Lactate Dehydrogenase; D005947:Glucose