SPDL1 and acute respiratory distress syndrome: Next, we evaluated the therapeutic effect of sPD-L1 mRNA-DOTAP-LNPs (0.2 mg/kg) on ARDS, comparing it with PBS, PD-L1-Fc recombinant protein (0.8 mg/kg), and Luc mRNA-DOTAP-LNPs (0.2 mg/kg).