Pathogen inactivation of platelets using ultravioletC light: effect on in vitro function and recovery and survival of platelets

BACKGROUND: We evaluated the effect of treating platelets (PLTs) using ultraviolet (UV)C light without the addition of any photosensitizing chemicals on PLT function in vitro and PLT recovery and survival in an autologous radiolabeled volunteer study. STUDY DESIGN AND METHODS: For in vitro studies, pooled or single buffy coatderived PLT concentrates (PCs) were pooled and split to obtain identical PCs that were either treated with UVC or untreated (n=6 each) and stored for 7 days. PLT recovery and survival were determined in a two-arm parallel autologous study in healthy volunteers performed according to BEST guidelines. UVC-treated or untreated PCs (n=6 each) were stored for 5 days and were compared to fresh PLTs from the same donor. RESULTS: There were no significant differences on Day7 of storage between paired UVC-treated and control PC units for pH, adenosine triphosphate, lactate dehydrogenase, CD62P, CD63, PLT microparticles, and JC-1 binding, but annexinV binding, lactate accumulation, and expression of CD41/61 were significantly higher in treated units (p<0.05). Compared with control units, the recovery and survival of UVC-treated PC were reduced after 5 days of storage (p<0.05) and when expressed as a percentage of fresh values, survival was reduced by 20% (p=0.005) and recovery by 17% (p=0.088). CONCLUSION: UVC-treated PLTs stored for 5 days showed marginal changes in PLT metabolism and activation in vitro and were associated with a degree of reduction in recovery and survival similar to other pathogen inactivation systems that are licensed and in use.