Fig. 1. Elevated circulating levels of mtDNA and STING activation are associated with disease severity in septic patients.

a mtDNA (ND2, D-loop) was measured in patients with sepsis with and without ALI. b The correlation between the serum level of mtDNA and duration of MV was assessed using the Spearman correlation test. c The correlations between the serum level of mtDNA and biomarkers of lung injury were assessed using the Spearman correlation test. d Western blot analysis of STING and autophagy signaling in PBMCs from patients with or without ALI. Two-tailed Student’s t-test was used to determine statistical significance, *p < 0.05; **p < 0.005; ***p < 0.0001. ns not significant. e Correlation matrix for circulating levels of mtDNA and blood biomarkers in critically ill patients.