title: Study of CD69 antigen expression and integrity of leukocyte cellular membrane in stored platelet concentrates following irradiation and treatment with Mirasol® PRT System.
abstract: BACKGROUND
  Leukocytes in transfused blood components, particularly residual lymphocytes, have been shown to contribute to the occurrence of various adverse reactions. One of the most severe is transfusionassociated graft versus host disease (TA-GvHD) following transfusion of blood components contaminated with immunocompetent T lymphocytes. Irradiation is a routine method for protection against TA-GvHD. According to the literature, some pathogen reduction methods have also been proven effective for the inactivation of T lymphocytes, and so they may be considered as an alternative to irradiation.
  
  
  OBJECTIVE
  Comparison of CD69 antigen expression and the integrity of the leukocyte cellular membrane in stored platelet concentrates (PCs) following irradiation with the Gammacell 3000 Elan (Nordion Inc., Ottawa, Canada) and treatment with the Mirasol® Pathogen Reduction Technology (PRT) System (Terumo BCT, Lakewood, USA).
  
  
  METHODS
  The study included seven experiments. For each experiment we used 3 PCs, for Mirasol® PRT System treatment (M), for Gammacell 3000 Elan irradiation (R), and for the control (C). 7-amino-actinomycin D (7-AAD, Becton Dickinson, Franklin Lakes, USA) permeability was used to determine lymphocyte viability while CD69 antigen expression was the marker of lymphocyte activation. Analyses of 7-AAD and CD69 antigen expression were performed in a FACS Canto I flow cytometer (Becton Dickinson, USA).
  
  
  RESULTS
  During 6 storage days, viable lymphocyte count decreased to 28% (p = 0.001) in the Mirasol® PRT System treated PCs and to 65% (p = 0.004) in the irradiated PCs. A statistically significant increase in CD69 expression in the irradiated PCs was observed; 1.3-fold on day 3 and 1.5-fold on day 6. In the Mirasol ® PRT System treated PCs, no statistically significant increase was observed.
  
  
  CONCLUSIONS
  The in vitro results suggest that the Mirasol® PRT System is as effective as irradiation due to donor leukocyte inactivation capacity.
authors.affiliation: Department of Transfusion Medicine, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Lachert
authors.affiliation: Department of Diagnostics for Hematology, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Woźniak
authors.affiliation: Department of Transfusion Medicine, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Antoniewicz-Papis
authors.affiliation: Department of Diagnostics for Hematology, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Krzywdzińska
authors.affiliation: Department of Transfusion Medicine, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Kubis
authors.affiliation: Department of Transfusion Medicine, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Mikołowska
authors.affiliation: Department of Transfusion Medicine, Institute of Hematology and Transfusion Medicine, Warszawa, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Letowska
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D001792:Blood Platelets; D005434:Flow Cytometry; D006086:Graft vs Host Disease / Q000276:immunology* / Q000517:prevention & control; D006801:Humans; D037181:Lectins, C-Type / Q000032:analysis*; D008213:Lymphocyte Activation / Q000187:drug effects / Q000528:radiation effects; D017713:Platelet Transfusion / Q000009:adverse effects / Q000379:methods*; D012256:Riboflavin / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000528:radiation effects*; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D015415:Biomarkers; D037181:Lectins, C-Type; D012256:Riboflavin; D000099192:CD69 Antigens
keywords: CD69; blood component; leukocyte viability