ICAM-1 expression is upregulated in the umbilical vein endothelial cells in acute chorioamnionitis with foetal inflammatory response.

Introduction: ICAM-1 is an adhesion molecule expressed on the endothelial cells and is involved in regulating leukocyte recruitment to the site of inflammation. Elevated ICAM-1 mRNA expression was found in the serum of mothers with chorioamnionitis. This study aimed to determine the expression of ICAM-1 in the placenta and umbilical cord of pregnancy with chorioamnionitis, and its association with adverse neonatal outcome.

Materials and methods: This study comprised a total of 86 cases of which there were 35 cases of non-chorioamnionitis and 51 cases of chorioamnionitis consisting of acute subchorionitis/chorionitis (maternal inflammatory response (MIR) stage 1, n=17), acute chorioamnionitis (MIR stage 2, n=17) and acute necrotising chorioamnionitis (MIR stage 3, n=17). Formalin-fixed paraffin embedded placenta tissue blocks were retrieved from the histopathology archive. ICAM-1 immunohistochemistry was performed on all cases and their expressions were evaluated on cells of the umbilical vein, umbilical artery, foetal vessels and maternal vessels.

Results: The expression of ICAM-1 in umbilical vein was significantly associated with cases of foetal inflammatory response (p<0.001).

Conclusion: We found that ICAM-1 expression was upregulated in the endothelial cells of umbilical vein in acute chorioamnionitis with positive foetal inflammatory response. ICAM-1 might be involved in the pathogenesis of acute chorioamnionitis and funisitis. Further study using a larger cohort is needed to strengthen this observation.