Prolonging shelf-life of platelets by low-level laser

Abstract

It remains significant challenges to extend a shelf life of platelets beyond the conventional five days. Unlike red blood cells that can be stored at 4°C for a few weeks, platelets are stored at room temperature only, which results in a gradual loss of their quality owing to a switch of energy metabolism from aerobic oxidative phosphorylation toward anaerobic glycolysis. Given the well-documented beneficial effect of near infrared low-level laser (LLL) on mitochondrial functions in a variety of cells under stress, we explored a potential for LLL to extend the shelf life of platelets beyond the five days. We found that exposure of a platelet-containing storage bag to LLL at 830nm at 0.5J/cm2 prior to storage could significantly retain a pH value and viability of the platelets stored within the bag under a standard condition for eight days with improved quality compared to those platelets stored similarly for five days in controls. LLL inhibited reactive oxygen species (ROS) and lactate production, but sustained ATP production, mitochondrial membrane potential, and morphology in the stored platelets. While preserving their metabolic activity, LLL didn’t activate platelets but increased their aggregation capacity and in vivo survival as suggested by similar levels of surface CD62p expression and enhanced agonist-induced aggregation and recovery following infusion in the presence compared to the absence of LLL treatment. This simple, addition-free, cost-effective, noninvasive laser illumination can be readily incorporated into the current platelet storage system to prolong shelf life of platelets with improved quality of stored platelets.