Dr. Karen Hirschi’s laboratory in Cell Biology (along with collaborators from Yale University and Stanford University) are attracting considerable attention for two papers published in December, 2020 (Inside UVa and CBS channel 19 news). Dr. Hirschi’s laboratory is already one of the leading laboratories in the world studying the production of blood cells from a subset of vascular endothelial cells (referred to as the endothelial-to-hematopoietic transition or EHT).
This is a normal developmental process but a careful understanding of its mechanism could provide clinical tools for producing blood stem cells outside the human body for patients with a variety of conditions. In a paper published in December in Science, Hirschi and her colleagues showed that the pattern of N-glycosylation of various proteins, such as Adam-10, in endothelial cells regulates EHT. The regulation of N-glycosylation of endothelial glycoproteins is itself regulated by a microRNA, miR-223. In a paper published in December in Cell Reports, Hirschi and colleagues showed that retinoic acid signaling is required for the specification of human blood-forming, or hemogenic, endothelial cells. They developed a protocol for deriving endothelial cells from human stem cells and for specifying them as hemogenic endothelial cells. This work has enormous implications for regenerative medicine.