Alarmin high mobility group box-1 in maternal serum as a potential biomarker of chorioamnionitis-associated preterm birth

Chorioamnionitis is associated with an increased risk of spontaneous preterm birth. The aim of this study was to investigate the serum levels of high mobility group box-1 (HMGB1) in pregnancies with histological chorioamnionitis (HCA)-associated preterm labor (PTL) with intact membranes or preterm premature rupture of membranes (PPROM), and to access the role of serum HMGB1 in HCA and HCA-associated PTL. A total of 190 pregnant women were enrolled in this study: PLT patients with (n=28) or without HCA (n=36), PPROM patients with (n=26) or without HCA (n=65), and non-HCA PTL controls (n=35). Maternal serum levels of HMGB1 were measured by enzyme-linked immunosorbent assay. Serum HMGB1 levels were significantly higher in PTL or PPROM patients than in control group (p<0.01, respectively). The PPROM patients also exhibited higher serum HMGB1 levels compared to PTL patients (p=0.015). HCA patients were characterized by significantly increased levels of serum HMGB1 when compared with non-HCA patients (p<0.01). Therefore, maternal serum HMGB1 may become a potential biomarker of HCA and HCA-associated PTL.