A large team of researchers from the Human Cell Atlas Initiative, led by the Wellcome Sanger Institute in the UK, has discovered that determining how the yolk sac develops during the first weeks of pregnancy is central to understanding the development of the immune system.
“This is the first time we’ve shown the multi-organ function of the yolk sac, as we’ve seen a progression from the yolk sac to the liver, to the bone marrow.”
Investigations indicate that our yolk sac is the source of the first blood cells, not just the oxygen-carrying red variety, but white cells that act as an immune response, and which travel from the yolk sac to the liver and then on to the bones where they lodge to help form marrow.
Compiled from nearly 170,000 cells from the human yolk sac, this reference library has formed a highly detailed ‘atlas’ of 15 broad classes of tissue types that not only produced blood cells, but contributed to a variety of important early functions. This small mass of tissue has a crucial role in the emergence of a wide variety of systems.
As with most other mammals, our yolk sac functions as an ‘early producer’ of blood cells, clotting factors, and metabolic enzymes, even without the yolk present, and its transient structure plays an important role in breaking down sugars and fats, dealing with toxins, and tracking the growth and dispersal of immune cells. Quickly, according to a study published in the journal Science Alert.
Study scientists said knowing how the yolk sac guided key parts of our early development could guide future theories about disease, or improve the processes of artificially grown tissues and organs.
Bioinformatics scientist and co-first author, Isaac Goh, confirmed, “It has given us new insights into the oldest blood and immune cells that our bodies produce, building on work that has been uncovered in previous studies from the Human Cell Atlas. jobs so far.