Placental Protein 13 Clusters Facilitate Trophoblast Invasion
PP13-mediated decidual necrosis zones may divert maternal immune system from spiral arterioles
TUESDAY, Oct. 11 (HealthDay News) -- Placental protein 13 (PP13 or galectin 13) forms perivenous aggregates that attract and activate maternal immune cells to create decidual zones of necrosis (ZONEs), which facilitate trophoblast invasion and conversion of the maternal spiral arterioles in preeclampsia, according to a study published online Oct. 11 in Reproductive Sciences.
Harvey J. Kliman, M.D., Ph.D., from Yale University in New Haven, Conn., and colleagues assessed the role of PP13 in trophoblast invasion and decidual necrosis in early preeclampsia. Immunohistochemical analysis was carried out on 20 elective pregnancy termination specimens between 6 and 15 weeks of gestation to assess PP13, immune cells, human placental lactogen, cytokeratin, and markers of apoptosis.
The investigators found that PP13 was localized to the occasional multinucleated luminal trophoblasts within converted decidual spiral arterioles, and to syncytiotrophoblasts in the chorionic villi. PP13 staining was not seen in cytotrophoblasts, anchoring trophoblasts, or invasive trophoblasts. Extracellular PP13 aggregates were localized around ZONEs which comprised decidual veins associated with T-cells, neutrophils, and macrophages.
"Our studies suggest that PP13-mediated ZONEs within normal human gestational decidua may be a novel mechanism to divert maternal immune surveillance away from the spiral arterioles," the authors write.
Several of the study authors disclosed financial ties with Diagnostic Technologies Ltd.