Enhanced S100B expression in T and B lymphocytes in spontaneous preterm birth and preeclampsia

S100B belongs to the family of danger signaling proteins. It is mainly expressed by glial-specific cells in the brain. However, S100B was also detected in other cell likewise immune cells. This molecule was suggested as biomarker for inflammation and fetal brain damage in spontaneous preterm birth (sPTB), preeclampsia (PE) and HELLP (hemolysis, elevated liver enzymes, and low platelet count).

The aim of our study was to determine the concentration of S100B in maternal and cord blood (CB) plasma and placenta supernatant as well as the expression of S100B in maternal and CB CD4+ T cells and CD19+ B cells in sPTB and patients delivering following PE/HELLP diagnosis compared to women delivering at term (TD). The S100B expression was further related to the birth weight in our study cohort.

S100B concentration was enhanced in maternal and CB plasma of sPTB and PE/HELLP patients and positively correlated with interleukin-6 (IL-6) levels. Increased S100B was also confirmed in CB of small-for-gestational-age (SGA) infants. S100B expression in maternal blood was elevated in CD4+ T cells of PE/HELLP patients and patients who gave birth to SGA newborns as well as in CD19+ B cells of sPTB and PE/HELLP patients and patients with SGA babies. In CB, the expression of S100B was increased in CD19+ B cells of sPTB, PE/HELLP and SGA babies.

Our results support the hypothesis that S100B expression is enhanced in inflammatory events associated with preterm birth and that S100B expression in immune cells is a relevant marker for inflammation during pregnancy complications.