Effect of FTY720 on transfusion-related acute lung injury: a preliminary investigation

Objective To investigate the effects and mechanisms of different doses of fingolimod (FTY720) on non-antibody-mediated transfusion-related acute lung injury (TRALI). Methods A TRALI mouse model was constructed using lipopolysaccharide (LPS) pre-stimulation and platelets (Plt) of different storage days for second strike. The success of the modeling was determined by protein concentration in lung tissue homogenates, myeloperoxidase (MPo) activity, lung wet/dry weight ratio (W/D ratio), lung tissue damage score and pathological sections. Ceramide and sphingosine-1-phosphate (S1P) contents in platelets of different storage days were detected. FTY720 was administered 1 h after LPS injection to investigate the role of FTY720 in TRALI. The expression levels of vascular endothelial cadherin (VE-cadherin) and zonula occludens-1 (ZO-1) were analyzed by WB. Results Mice infused with stored 5-day Plt (d5Plt group) exhibited typical signs of TRALI, and the differences in lung tissue homogenate protein concentration (6 546