The thymus is a gland that makes T cells, which protect the body against infection. Although originally it was thought that the thymus only produces T cells, there is now evidence showing that the thymus also supports the development of other white blood cells. Our research focuses on defining the stem cell that gives rise to these white blood cells, and delineates the developmental pathway within the tissue.
Impact
In order to boost immunity in settings of immune deficiencies, or during treatment with stem cell transplantation, it is important to understand which stem cell gives rise to the white blood cells within the thymus. The current gene therapy protocols target all the stem cells, which brings high costs and reduced efficiency. By targeting the right stem cells, costs will be significantly reduced and higher purity of the product will lead to a better outcome.
reNEW research
Based on markers that are expressed on the surface of the stem cells we defined a population that exits the bone marrow, traffics through the blood and seeds the thymus. In a culture system we can reproduce the development into the different white blood cells. Currently, we are investigating the anatomical structures within the thymus to visualize where the development exactly occurs and which cellular interactions are required.
Image description
Human thymus. The colors indicate different structures/cell types. Cells enter the tissue via the blood vessels in yellow. The chemokine in blue attracts and retains the stem cells and white blood cells in the tissue.
Credits
Janine Melsen post-doc and students Isabelle Koster & Anne Tom, Frank Staal lab, reNEW Leiden.
