In our present study, we detected the expression of surface markers (CD80, CD86, CD40, MHC II, B220, CD11b, ICAM-1, CCR7) to reflect the effect of the HMGB1/PI3K/Akt/mTOR signaling pathway on the phenotype and function of DCs in ALI. The gene discussed is CD40; the disease is acute respiratory distress syndrome.