Single cell RNA-sequencing of murine endothelial and stromal populations at embryonic day 17 (E17)

The origin of bone marrow stromal cells (BMSCs) is not completely understood. We have identified a rare population of cells with a transcriptional profile consistent with endothelial to mesenchymal transition (Endo-MT) in human fetal development. Therefore, we hypothesized that Endo-MT contributes to bone marrow niche formation in mammals. Here, we sought to determine whether Endo-MT cells could be identified in murine bone marrow during embryonic development. We isolated bone marrow and collagenased bone fraction from long bones of 9 fetuses at embryonic day 17 (E17) and FACS purified endothelial cells and BMSCs for single cell RNA sequencing.