Leukocyte-associated immunoglobulin-like receptor 1 (LAIR1) is reduced with preeclampsia and small for gestational aged fetuses.

Leukocyte-associated immunoglobulin-like receptor 1 (LAIR1) is an inhibitory receptor expressed on immune cells. We evaluated LAIR1 in placentas from preeclamptic or small for gestational age (SGA) pregnancies, and placental explant model (1 % O2, IL6 and TNFα, or control). LAIR1 mRNA was reduced in placentas from preeclamptic (p < 0.0001, n = 78) and SGA (p < 0.0001, n = 32) pregnancies. LAIR1 protein expression was reduced in placentas from preeclampsia (p < 0.0001, n = 43) and SGA (p = 0.009, n = 10) pregnancies. Hypoxia (1 % O2) reduced LAIR1 mRNA expression in placental explants (p = 0.008). These findings suggest hypoxia modulates LAIR1 expression in the placenta.