Expression of laminin receptor 1 in human placentas from normal and preeclamptic pregnancies and its relationship with the severity of preeclampsia.

Objectives: To investigate the expression of laminin receptor 1 (LR1), a non-integrin-type laminin receptor, in preeclamptic and normal third-trimester placentas, as well as to investigate whether its expression differs with disease severity.

Study Design: Third trimester placental samples obtained from deliveries of preeclamptic (n=34) and normotensive healthy pregnant women (n=35) were immunohistochemically studied for the expression of LR1. The placentas from both mild (n=14) and severe (n=20) preeclamptic pregnancies were further assessed for strength of LR1 expression according to disease severity.

Results: When compared with normal placentas, the staining with LR1 protein in cytotrophoblasts and syncytiotrophoblasts was lower in preeclamptic placentas (P<0.05 and P<0.01, respectively). The intensity of staining with LR1 in decidual cells, cytotrophoblasts, syncytiotrophoblasts, and extracellular matrix cells of preeclamptic placentas did not vary with disease severity (P>0.05).

Conclusions: Decreased LR1 expression in cytotrophoblasts and syncytiotrophoblasts of preeclamptic placentas, which may be independent of disease severity, might have a role in shallow trophoblastic invasion in preeclampsia.