HMGB1 (total, acetylated) and K18 (apoptotic, necrotic) were identified and quantified by novel LC-MS/MS assays in APAP overdose patients (n = 78).
HMGB1 (total; 15.4 ¡À 1.9 ng/ml, p <0.01, acetylated; 5.4 ¡À 2.6 ng/ml, p <0.001), cK18 (5649.8 ¡À 721.0 U/L, p <0.01), and FL-K18 (54770.2 ¡À 6717.0 U/L, p <0.005) were elevated in the sera of APAP overdose patients with liver injury compared to overdose patients without liver injury and healthy volunteers. HMGB1 and FL-K18 correlated with alanine aminotransferase (ALT) activity (R2 = 0.60 and 0.58, respectively, p <0.0001) and prothrombin time (R2 = 0.62 and 0.71, respectively, p <0.0001). Increased total and acetylated HMGB1 and FL-K18 were associated with worse prognosis (King¡¯s College Criteria) or patients that died/required liver transplant compared to spontaneous survivors (all p <0.05-0.001), a finding not reflected by ALT and supported by ROC analysis. Acetylated HMGB1 was a better predictor of outcome than the other markers of cell death.
K18 and HMGB1 represent blood-based tools to investigate the cell death balance clinical APAP hepatotoxicity. Activation of the immune response was seen later in the time course as shown by the distinct profile of acetylated HMGB1 and was associated with worse outcome.