Vitamin D receptor (VDR) expression and its immunological role within the placenta

Vitamin D metabolism plays a pivotal role not only in bone metabolism but in a variety of tissues such as the placenta. This organ forms the feto-maternal interface, where Vitamin D deficiency and a dysregulation of its receptor VDR can lead to dysfunction and consequently adverse fetal and maternal outcomes. Moreover, it hasbeenshownthat the reaction tomaternal immunological triggers, such as inflammation or infection, is linked to altered expression profiles of VDR. In a murine study we showed that maternal schistosome infection indeed affects placental VDR expression and resulted in suppressed susceptibility to allergic airway inflammation in offsprings. To reproduce thesefindings inahumansetting,wemonitored in more detail the VDR expression in placenta samples. We have now started a pilot study (Placenta-Cordblood-Microbiome Study), comparing placentas from healthy German cohorts with patients from Gabon, where schistosomiasis is endemic. We analyzed gene expression levels, focusing not only on VDR expression but also other candidate genes like IL-10 or IFNy. To link VDR expression profiles to the offspring’s allergy susceptibility, we will perform detailed allergy questionnaires until up to five years after child’s birth. Our preliminary data, so far, indicates that VDR gene expression profiles are even varying between the fetal and the maternal side of the placenta, emphasizing its important role within this organ.