Pathogen reduction treatment of buffy coat platelet concentrates in additive solution induces proapoptotic signaling.
BACKGROUND
Pathogen reduction technology (PRT) can potentially reduce the risk of transfusion-transmitted infections. However, PRT treatment of platelet (PLT) concentrates also results in reduced PLT quality and increased markers of apoptosis during storage. The aim of this study was to investigate changes to the expression and activation of proteins involved in apoptosis signaling.


METHODS
Samples from riboflavin and ultraviolet light PRT-treated and untreated (control) buffy coat-derived PCs in 70% SSP+ and 30% plasma were taken on Days 1, 5, and 7 of storage. Phosphatidylserine (PS) exposure, expression of Bcl-2 family proteins, cytochrome c release, and cleavage of caspase-3 and caspase-3 substrates were analyzed using flow cytometry and Western blotting.


RESULTS
Compared to untreated controls, markers of apoptosis signaling were increased after PRT and subsequent storage. PS exposure on the PLT outer membrane was significantly higher after PRT on Days 5 and 7 of storage (p < 0.05). Expression of proapoptotic Bak and Bax was higher after PRT and subsequent storage. Cytochrome c release and caspase-3 cleavage were also greater and occurred earlier in the PRT-treated PLTs. The cleavage of caspase-3 substrates gelsolin and ROCK I were also increased after PRT, compared to untreated controls.


CONCLUSIONS
This study demonstrated an increase in proapoptotic signaling during PLT storage, which was exacerbated by PRT. Many of these differences emerged outside the current 5-day storage period. These changes may not currently influence PLT transfusion quality, but will need to be carefully evaluated when considering extending PLT storage beyond 5 days.
Research and Development, Australian Red Cross Blood Service, and the School of Medical and Molecular Biosciences, University of Technology, Sydney, New South Wales, Australia.
Samantha
S
Reid
Lacey
L
Johnson
Narelle
N
Woodland
Denese C
DC
Marks
D000328:Adult; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D051017:Apoptosis Regulatory Proteins / Q000097:blood*; D015415:Biomarkers; D058621:Blood Buffy Coat / Q000166:cytology*; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D001793:Blood Preservation; D058731:Blood Safety; D017848:Blood-Borne Pathogens / Q000187:drug effects / Q000528:radiation effects; D053148:Caspase 3 / Q000097:blood; D002469:Cell Separation / Q000379:methods; D045304:Cytochromes c / Q000097:blood; D018562:Disease Transmission, Infectious / Q000517:prevention & control; D018260:Gelsolin / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000097:blood; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D019188:Organ Preservation Solutions / Q000494:pharmacology*; D017713:Platelet Transfusion; D012256:Riboflavin / Q000494:pharmacology*; D013997:Time Factors; D014466:Ultraviolet Rays; D054460:rho-Associated Kinases / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers; D018260:Gelsolin; D008565:Membrane Proteins; D019188:Organ Preservation Solutions; D045304:Cytochromes c; C515851:ROCK1 protein, human; D054460:rho-Associated Kinases; C505407:CASP3 protein, human; D053148:Caspase 3; D012256:Riboflavin