TNFα and MFG-E8: Novel Biomarkers to Predict Implantation Failure

The investigators hypothesize that TNFα and MFG-E8 cooperatively maintain the integrity of the normal endometrium, and that in patients with IF or with recurrent pregnancy loss (RPL) of unexplained origin, excessive TNFα increases the maternal shedding of MFG-E8, disrupting the normal protective effect of this protein, resulting in damage of the endometrial epithelium and impairing trophoblast invasion. The investigators propose that these molecules can be measured in local tissue (endometrium) as well as in serum as a reflection of increased inflammation and can therefore be used as markers of implantation and its failure. The investigators hypothesis is that TNFα is up-regulated in serum of women with implantation defects (IF and RM of unexplained origin) and this causes perturbation of MFG-E8 secretion. These results will provide first evidence demonstrating endometrial dysfunctions resulting from over-expression of pro-inflammatory molecules. The release of significant quantities of these molecules into serum broadens the maternal-fetal interface beyond the uterus and into the maternal circulation. The characterization of these molecules is essential to better understand, not only their biological effects, but also their potential as prognostic and diagnostic biomarkers for detection of IF. More importantly, these molecules could be potential therapeutic targets (perhaps intrauterine infusion of MFG-E8 for tissue repair, and/or oral administration of TNFα antagonists) to improve implantation outcomes. Two recent studies have reported the successful therapeutic use of recombinant human MFG-E8 (rhMFG-E8) in animals: one was used to decrease intestinal injury after whole body radiation (Ajakaiye et al, 2012), and the other was to mitigate inflammation and tissue injury after hemorrhagic stroke (Wang et al, 2012). Also, TNFα inhibitors have been shown to significantly increase IVF outcome in infertile patients (Winger et al, 2009 and 2008). In summary, these two pivotal studies show promising clinical uses of rhMFG-E8 in tissue repair/remodeling by decreasing apoptosis, and provide basis for their use as candidates for further clinical development in reproductive health.

Objectives: Here, the investigators seek to delineate novel diagnostic methods with the ultimate long term goal of designing directed therapies to improve embryo implantation competence.

• The specific aim is to quantify and correlate MFG-E8 and TNFα in serum and in endometrial biopsies of women in 3 groups: controls, IF and RM.
• The ultimate goal of this study is to provide data leading to a simple and quick test to measure soluble serum markers of IF/RM in order to discriminate prospectively between these groups of patients.
• To translate these findings into the use of modulators of these inflammatory molecules to improve pregnancy rates in patients with predicted implantation defects. It is widely known that "classic" markers of endometrial receptivity such as those provided by an invasive endometrial biopsy (with Hematoxilin-Eosin staining, or immuhistochemistry, or even with microarray technology) are not reliable to establish clear-cut diagnosis due to cycle-to-cycle variations and overlap of results.