F12 and acute respiratory distress syndrome: In an ARDS model constructed on a PCLS, it was found that coagulation factor XII (FXII), mainly involved in the intrinsic coagulation pathway, increases rapidly in the early stage of ARDS and can promote the release of inflammatory factors such as interleukins (IL-8, IL-1β, and IL-6), leukemia inhibitory factor (LIF), CXC chemokine ligand-5 (CXCL5), and tumor necrosis factor-alpha (TNF-α) (Figure 3) [51].