Publications by authors named "Wafaa Essahib"
Study Question: Which processes and transcription factors specify the first and second lineage segregation events during human preimplantation development?
Summary Answer: Differentiation into trophectoderm (TE) cells can be initiated independently of polarity; moreover, TEAD1 and YAP1 co-localize in (precursor) TE and primitive endoderm (PrE) cells, suggesting a role in both the first and the second lineage segregation events.
What Is Known Already: We know that polarity, YAP1/GATA3 signalling and phospholipase C signalling play a key role in TE initiation in compacted human embryos, however, little is known about the TEAD family of transcription factors that become activated by YAP1 and, especially, whether they play a role during epiblast (EPI) and PrE formation. In mouse embryos, polarized outer cells show nuclear TEAD4/YAP1 activity that upregulates Cdx2 and Gata3 expression while inner cells exclude YAP1 which upregulates Sox2 expression.
Article Synopsis
- * Sixteen patients were analyzed, and all samples tested negative for SARS-CoV-2 RNA, with no inflammatory issues found in the endometrial tissue; this suggests that the virus may not impact fertility in these cases.
- * The findings indicate no viral RNA was detected, but caution is advised due to the small sample size, and further research is needed regarding potential risks to embryos during ART procedures in SARS-CoV-2-positive women.
Objective: To study whether endometrial epithelial podocalyxin (PCX) inhibits implantation of human embryos in vitro and in patients undergoing in vitro fertilization (IVF).
Design: We have recently identified PCX as a key negative regulator of endometrial epithelial receptivity. Podocalyxin is expressed in all epithelial cells in the nonreceptive endometrium, but is selectively downregulated in the luminal epithelium (LE) for receptivity.
SARS-CoV-2 host receptors ACE2 and CD147 (BSG) are present on human oocytes and blastocysts.
J Assist Reprod Genet
November 2020
Purpose: To visualize SARS-CoV-2 host receptors ACE2 and CD147 on human oocytes and blastocysts.
Methods: Immunohistochemistry and confocal microscopy on human primary oocytes and pre (5 days post fertilization (dpf5) and (dpf6))- and peri (dpf7)-implantation blastocysts donated to research.
Results: SARS-CoV-2 host receptors ACE2 and CD147 are present on the membrane of trophectoderm, epiblast and hypoblast cells in human blastocysts.