Fig. 5

Notch1 (N1) expression in endothelial cells, mural cells and macrophages in the peri-implantation uterus. H&E and double staining IF of E3.5 (A – E) and E6.5 (F – J) uterine sections. Ovals indicate areas of the uteri magnified (B1 – E1 and G1 – J1). (A) H&E at E3.5 highlighting the luminal epithelium (arrows), inner circular and outer longitudinal myometrium [dashed bracket (myo)], endometrial stroma (st) and serosa (s). (B – E) Notch1⁺ cells are observed throughout the endometrial stroma, myometrium and serosa at E3.5. Low levels of Notch1 are detected in the luminal (arrows) and glandular epithelium (g). (B) Notch1 and CD31. Notch1 is expressed in CD31⁺ ECs. NG2⁺ mural cells (C) and PDGFR-β⁺ mural cells (D) are associated with Notch1⁺ cells in the stroma, myometrium, and serosa. (E) Notch1 and F4/80. F4/80 labels macrophages in stroma, myometrium and serosa. F4/80⁺ macrophages are adjacent to Notch1⁺ cells (arrowheads in E1). (F) H&E at E6.5 highlighting the embryo (e), inter-implantation sites (i), and myometrium (myo). (G – J) Notch1⁺ cells are observed throughout the decidua and inter-implantation sites at E6.5. (G) Notch1 and CD31. Notch1 is expressed in CD31⁺ decidual ECs. (H) Notch1 and NG2. NG2⁺ mural cells are associated with Notch1⁺ cells in the decidua. (I) Notch1 and PDFGR-β. PDGFR-β⁺ mural cells are associated with Notch1⁺ cells in the decidua. (J) Notch1 and F4/80. F4/80⁺ macrophages are not associated with Notch1⁺ cells in the decidua, myometrium and inter-implantation sites. DAPI identifies all nuclei in IF images. am, anti-mesometrial; m, mesometrial. Bar in A and F = 100 μm. Bar in B – E and G – J = 500 μm. Bar in B1 – E1 and G1 – J1 = 50 μm.