Comparative analysis of mouse and human placentas across gestation reveals species-specific regulators of placental development [human]

In this study, we compared the genome-wide transcriptome of mouse and human placentas across gestation to identify species-specific signatures of early development. We also compared human placental signatures to purified primary cytotrophoblasts (CTB) isolated from placentae at different gestational age. In order to characerise the human cytotrophoblast (CTB) cells niche, we performed genome-wide expression profiling of human placental specimen from week 4 to term and compared these profiles to those of mouse placentas from E7.5 to E18.5. Three to five biological replicates were chosen for each week of gestation from week 4 to week 12; seven second trimester (week 14-16) and five term placental samples were also included. Sample gestational age was defined according to the completed week of gestation (i.e. placentas at week 4 day 0, through week 4 day 6 were defined as “week 4”). For placentas from pre-viable gestations, “normal” is defined as a singleton pregnancy without any detectable fetal abnormalities on ultrasound; for term placentas, “normal” is defined by a non-hypertensive, non-diabetic singleton pregnancy, where the placenta is normally grown and shows no gross or histologic abnormalities.