No differences in HMGB1 levels were present between the different patient subgroups (No lung involvement: 3.3 [1.7-5.2]; ILD: 3.6 [1.3-5.7]; PAH: 3.9 [2.0-5.1]; ILD+PAH: 3.9 [1.4-7.3]) (Figure 1). Here, HMGB1 is linked to pulmonary arterial hypertension.