BioProject

The use of in vitro fertilization (IVF) has revolutionized the treatment of infertility and is now responsible for 1-5% of all births in industrialized countries. More...

The use of in vitro fertilization (IVF) has revolutionized the treatment of infertility and is now responsible for 1-5% of all births in industrialized countries. During IVF, it is typical for patients to generate multiple embryos. However, only a small proportion of them possess the genetic and metabolic requirements needed in order to produce a healthy pregnancy. The identification of the embryo with the greatest developmental capacity represents a major challenge for fertility clinics. Current methods for the assessment of embryo competence are proven inefficient and the inadvertent transfer of non-viable embryos is the principal reason why most IVF treatments (approximately two-thirds) end in failure. In this study, we investigate how the application of proteomic measurements could improve success rates in clinical embryology. We describe a procedure that allows the identification and quantification of proteins of embryonic origin, present in attomole concentrations in the blastocoel, the enclosed fluid filled cavity that forms within five-day old human embryos. By using targeted proteomics, we demonstrate the feasibility of quantifying multiple proteins in samples derived from single blastocoels, and that such measurements correlate with aspects of embryo viability, such as chromosomal (ploidy) status. This study illustrates the potential of high-sensitivity proteomics to measure clinically relevant biomarkers in minute samples and, more specifically, suggests that key aspects of embryo competence could be measured using a proteomic-based strategy, with negligible risk of harm to the living embryo. Our work paves the way for the development of “next-generation” embryo competence assessment strategies, based on functional proteomics. This subset of experiments were used to validate embryonic origin of proteins identified in the blastocoel cavity of the developing human embryo. Data from ICM and TE samples were combined to create a comprehensive list of genes expressed by the developing human blastocyst. The presence of the correlated transcript indicated embryonic origin of the protein. Overall design: Data were obtained from a total of ten embryos. For each embryo, Inner Cell Mass and Trophectoderm were separated and distributed into three paired replicates (three ICM and three TE). Two pairs were composed of pooled cellular material from three and one pair from four blastocysts. Each replicate was analysed separately and the list of active genes were combined. Embryos used in these experiments were Day 5/6 embryos deriving from fresh treatment cycles or embryos that were thawed at Day 3 of development and then cultured to blastocyst stage. Less...