Comparison between caruncles and intercaruncles in AI, IVF-ET and SCNT pregnancies. Bos taurus

Implantation is crucial for placental development whose quality will directly impact fetal growth and pregnancy success with possible consequences on post-natal health. We postulated that early perturbations of the conceptus-maternal environment communication may alter the endometrium physiology that could account for the final reproductive outcome. Using cattle as an animal model, we compared gene expression profiles of the endometrial caruncular and intercaruncular areas at implantation in three types of pregnancies, namely artificial insemination (AI), in vitro fertilization with embryo transfer (IVF-ET) or somatic cell nuclear transfer (SCNT). Less than 35% of the differentially regulated genes were found to be common between AI, IVF-ET, and SCNT conditions. Compared to AI, numerous biological functions and several canonical pathways and genes were found to be significantly affected in IVF-ET or SCNT, with a major impact on metabolism and immune function in SCNT. Our data show that endometrium can fine-tune its physiology and could be considered as a biological sensor in response to pregnancy manipulations. Determining the limits of the endometrial plasticity should bring new insights on the contribution of the maternal compartment to the issue of pregnancy. Keywords: Fluorescence Microarray Overall design: 30 samples