For the first time, scientists follow the development of individual immune cells in a living zebrafish embryo. Thanks to their translucent tissue the embryos can be observed live under the microscope. So the researchers could observe the real-time development of T-cells, starting with the formation of the thymic anlage, via the cells’ migration into the organ from the bone marrow, right up to the stage when the fully formed T-cells are released from the thymus. The new method could, amongst other things, help with the development of drugs to treat malfunctions of the thymus.
This image depicts a four-day-old zebrafish embryo. The immune cells are illmuniated in green; the thymus tissue in red. The eye is visible in the top part of the picture. © Isabel Hess/Immunity, 16 February 2012