Different expression of NOD2 in decidual stromal cells between normal and unexplained recurrent spontaneous abortion women during first trimester gestation.

The NOD2 gene, encoding intracellular paternal recognition receptor (PRR) also called caspase activation and recruitment domain 15 (CARD15), is mutated in Crohn's disease, an autoimmune-disorder. Unexplained recurrent spontaneous abortion (URSA) involved in complex auto-immune disorder. However, little is known about the expression of NOD2 protein at maternal-fetal interface with URSA patients. Our aim was to compare the expression levels of NOD2 in the decidual stromal cells (DSCs) from patients with normal pregnancy to those with unexplained recurrent spontaneous abortion (URSA) during first trimester pregnancy. Tissues and DSCs were collected from 12 patients with URSA and 26 patients with normal pregnancies that required abortion. DSCs in the normal pregnancy group showed significantly higher mRNA and protein levels of NOD2 than those isolated from the URSA group using real time PCR and in cell western. The appropriate expression of NOD2 in normal DSCs suggests that this protein may be required to sustain normal pregnancy.