KRT8 and acute respiratory distress syndrome: In addition, the expression levels of Claudin 4 and Keratin 8 proteins in the ARDS group were lower than in the Sham but increased under the TAG pretreatment (ARDS vs. TAG + ARDS, 0.48 ± 0.07 vs. 0.72 ± 0.06 and 0.44 ± 0.06 vs. 0.77 ± 0.05, respectively, p < 0.01; Figures 6E, F).