Influence of riboflavin and ultraviolet-light treatment on plasma proteins – protein S and alpha 2-antiplasmin – in relation to the time of administration

Abstract

Background/Aim. After introduction of carefull selection procedure for blood donors and the implemention of highly sensitive screening tests for transfusion transmissible infections (TTI), blood is very save product concerning TTI. Nevertheless, because of the ?window? period for the pathogen that are testing and the emergence of new pathogens, the risk stil persists. Implementation of pathogen reduction technology (PRT) provides a proactive approach to improve blood safety. By damaging nucleic acids, PRT selectively inactivates pathogens and leucocytes. However, during the process, plasma proteins are, also, damaged in some extent. The goal of this study is to conclude if there is the difference in the effect of PRT on Protein S and ?2-antiplasmin regarding the time of inactivation: inactivation immediately after plasma separation from whole blood (before freezing) versus inactivation after freezing/thawing. Methods. The voluntary donors' blood is taken into quadruple bag system, centrifuged and separated into blood products. Control's group plasma is inactivated by the Mirasol PRT system and frozen. Experimental's group plasma is frozen and, after four months, thawed and inactivated. Protein S and ?2-antiplasmin activity are examined in samples after separation, inactivation and thawing. Results. Analysing Protein S and ?2-antiplasmin activity, no statistically significant difference is found between the initial samples. The trend of reduction of protein's activity after inactivation and freezing/thawing is present in both groups but without statistically significant intergroup difference. Conclusion. Reduction in Protein S and ?2-antiplasmin's activity after immediate - before freezing and afterwards - after freezing/thawing inactivation does not show a statistically significant difference, making stored plasma unites suitable for safe and efficient inactivation directly before clinical use and according to patient's blood type.