To decipher the molecular pathways through which DNA-PKcs deletion mitigates endothelial dysfunction and microvascular damage during endotoxemia, label-free liquid chromatography-mass spectrometry (LC-MS) proteomics was used for unbiased analysis of protein expression profiles in CMECs isolated from DNA-PKcsf/f/Tie2Cre or control DNA-PKcsf/f mice in the presence of LPS. Here, PRKDC is linked to serum lipopolysaccharide activity.