Protein profile changes in platelet concentrates according to storage and leukoreduction - Analysis using proteomics technology

Background : Knowing how the protein profile of platelet products changes with storage or leukoreduction may give us greater insight into cell physiology and the cause of transfusion reactions other than cytokines and chemokines. Methods : We filtered four packs of platelet concentrates (PC) within 24 hr of blood collection and after 120 hrs of storage. Four aliquots of each supernatant in PC were obtained: pre-storage+prefiltration, pre-storage+post-filtration, post-storage+pre-filtration and post-storage+post-filtration. Routine chemistry tests and a two-dimensional electrophoresis (2-DE) were performed. The stained images were analyzed and the significant spots were identified using a peptide mass finger printing (PMF) with matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis after trypsin digestion. Results : The protein spots increased with storage and decreased after filtration (P<0.05, prestorage+ post-filtration). The spot density of various proteins, including macrophage inflammatory protein-2 alpha, megakaryocyte colony stimulating factor and interleukin-22 changed with storage and leukoreduction. Conclusions : The database of identified protein spots and their changes produced in this study is a useful basic tool for future studies on the mechanism of transfusion reactions. Further studies should validate the significance of each protein spot.