Amelioration of lesions associated with 24‐hour suboptimal platelet storage at 16 °C by a p38 MAPK inhibitor, VX ‐702

Background and Objectives Previous studies with p38 MAPK inhibitors at room temperature demonstrated that they improve a large number of platelet storage parameters, but cannot substantially inhibit p38 MAPK activation nor protect against widespread decrements in platelet quality parameters during 4 °C storage. In this study, platelet quality parameters and inhibition of p38 MAPK by VX ‐702 were studied after incubation of platelets at 16 °C without agitation, suboptimal storage conditions which produce moderate platelet decrements. Materials and Methods Trima apheresis units were collected and aliquoted into three 60‐ml CLX storage bags: (i) a control aliquot which was held at 20–24 °C with constant agitation; (ii) a test aliquot which was held at 20–24 °C with agitation until Day 2, when it was reincubated at 16 ± 1 °C for 24 ± 0·5 h without agitation and then returned 20–24 °C with agitation; (iii) a test aliquot containing 1 μm VX ‐702 stored in an identical fashion as aliquot 2. Aliquots were tested for an array of platelet storage parameters and p38 MAPK activation on Days 1, 4 and 7. Results Many platelet storage parameters and p38 MAPK activation were adversely affected by 24‐h incubation at 16 °C without agitation. With the exception of ESC , addition of VX ‐702 prevented p38 MAPK activation and the decrements in most observed parameters. Conclusion Unlike 4 °C storage, VX ‐702 prevents activation of p38 MAPK and decrements in many platelet storage parameters after exposure to 16 °C without agitation for 24 h.