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

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. Overall design: 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.