Plasma concentrations of high mobility group box protein 1 (HMGB1) and circulating DNA in patients with acute pancreatitis

Aims: Severe acute pancreatitis is characterized by inflammation but is also associated with necrotic pathways. HMGB1 recently identified as a late-acting proinflammatory cytokine, is secreted actively by living inflammatory cells, and released passively from necrotic or damaged cells. HMGB1 may therefore be related to inflammation and necrosis in acute pancreatitis. The aim of this study was to evaluate whether the level of HMGB1 is increased in the plasma in patients with acute pancreatitis. We further investigated whether the genomic DNA in plasma as a marker of cell death correlates with the disease severity or with the HMGB1 level. Patients and methods: Patients with acute pancreatitis (n=92) were grouped according to the severity of the disease on the basis of the Ranson scores. The control groups consisted of patients with sepsis of different origins (n=32) and healthy blood donors (n=30). HMGB1 was determined by ELISA, and plasma DNA by real time PCR detection of β-globin DNA. Results: The mean plasma HMGB1 levels were significantly higher in patients with acute pancreatitis (0.1–42.2ng/ml) than in healthy volunteers (0.01–0.13ng/ml), and comparable to, but higher than those in the plasma of patients with sepsis of different origins (0.1–25.0ng/ml). There was a significant difference in HMGB1 levels between patients with severe and mild acute pancreatitis (0.13–42.2ng/ml vs. 0.01–4.86ng/ml). There was no correlation between the levels of HMBG1 and free circulating DNA in the plasma. Elevated levels of plasma DNA were detected only in the plasma samples from patients with infected pancreas necrosis, and septic patients (45.5–120ng/ml and 45.2–345.7ng/ml respectively).

Conclusions: These results suggest that HMGB1 may act as a key mediator for inflammation in acute pancreatitis. The plasma HMGB1 levels were increased in acute pancreatitis, and correlated with the disease severity. In contrast, free circulating DNA in the plasma can not be regarded as a marker of pancreas necrosis.