Left: Ana Teresa Tavares. Right: Blood precursor cells (green) in a cross-section of the chick embryo aorta. Credit: Seco et al (2020)
Ana Teresa Tavares, investigator from Tissue Repair and Inflammation Lab led by António Jacinto, published an article in the journal Frontiers in Cell and Developmental Biology entitled "A Bird’s Eye View on the Origin of Aortic Hemogenic Endothelial Cells" (full article here).
In brief, Ana Teresa Tavares talks about this article, in which the researchers identify a new population of embryonic cells that gives rise to blood stem cells:
In the adult body, blood stem cells (or hematopoietic cells) are located in the bone marrow and are responsible for the constant replacement of all types of blood and immune cells. In the embryo, these stem cells arise from the wall of the aorta. Understanding their genesis is essential to the efficient production of blood stem cells in the laboratory (for example, from induced pluripotent stem cells) for the treatment of blood diseases as an alternative therapy to bone marrow transplantation.
The article recently published in the scientific journal Frontiers in Cell and Developmental Biology presents a new perspective on the embryonic origin of blood based on studies developed by the authors and other researchers over the past 50 years, using the avian embryo as an experimental model.
Avian embryos, such as those from chicken and quail, are used in research due to their similarities to mammalian embryos, but with the advantage of being easily accessible inside the egg. “To study the first stages of development, we take the embryo out of the egg and grow it in culture for two to three days, which allows us to observe the live embryo over that period,” explains Ana Teresa Tavares, the leading author of the work.
In the study now reported, the researchers developed a technique for labeling blood precursor cells with a fluorescent protein and tracking their path and fate in the cultured chicken embryo. “In this way we were able to not only identify the embryonic origin of blood stem cells, but also see and record the fascinating transformation of an aortic wall cell into a blood stem cell,” adds Ana Teresa Tavares.
The evidence analyzed in this article indicates that blood stem cells originate from progenitors called hemangioblasts. This discovery represents an important advance in the understanding of the blood development process, with potential application in the production of hematopoietic stem cells in culture for cell therapy.
This work was carried out at the Chronic Diseases Research Centre of NOVA Medical School (CEDOC-NMS) and at the Instituto Gulbenkian de Ciência (IGC) and funded by Fundação para a Ciência e a Tecnologia (FCT) and Lisboa Regional Operational Programme (Lisboa 2020).
Gabriel Martins, head of UIC: Advanced Imaging Unit at Instituto Gulbenkian de Ciência helped with the research design, image acquisition, and data analysis.
Discover more about the research of Ana Teresa Tavares and Tissue Repair and Inflammation Lab HERE.