Bart Weijts receives LSBR Postdoctoral Fellowship 6 January 2023 Bart Weijts receives LSBR Postdoctoral Fellowship Back to news Bart Weijts, a senior postdoctoral scientist from the group of Catherine Robin, receives a Postdoctoral Fellowship by The Landsteiner Foundation for Blood Transfusion Research (LBSR). He will use the fellowship to study a novel population of macrophages – cells that play an important role in the immune system – that he recently indentified in zebrafish embryos. LSBR fellowships are intended for young, creative and talented researchers trying to establish a new line of research. Macrophages in tissues Macrophages are immune cells that reside in the tissues of the body. Besides their task of protecting the tissue from potential threats such as pathogens and foreign particles, macrophages are also indispensable for the maintenance of tissue integrity in a wide range of organs. The cells are for example referred to as Red pulp macrophages in the spleen, where they mainly clear aged and defective red blood cells from the blood. Macrophages in the liver are called Kupffer cells and screen the blood from the portal vein for bacteria, endotoxins and foreign particles that might have been absorbed in the gut. Macrophages of the skin are the Langerhans cells, which mainly sample their environment for pathogens. While macrophages have been identified inside virtually all tissues of the body, they have never been reported to be inside blood vessels. Video: The movement of a macrophage in a blood vessel of a zebrafish embryo. Credits: Bart Weijts, copyright: Hubrecht Institute. Who patrols blood vessels and surveills blood for threats? With a total length of 100.000 kilometres, blood vessels of an adult human could circle the earth more than twice if laid in a straight line. Regarding it size and its vital importance for proper functioning of the body, it seems unlikely that there are no immune cells patrolling the blood vessels from the inside, for example to repair damage that might occur to the blood vessel wall or to eliminate foreign particles or pathogens that accidentally enter into the blood stream. By using zebrafish as a model, Bart Weijts, from the group of Catherine Robin, has identified a previously unrecognized population of macrophages that specifically resides within the blood vessels and perform exactly these functions. They repair injuries to the blood vessels, scavenge pathogens from the blood, and screen and clear damaged circulating cells. Postdoctoral Fellowship Bart Weijts has now been awarded a Postdoctoral Fellowship by the Landsteiner Foundation for Blood Transfusion Research (LSBR) for these findings. With the support of this fellowship, he will be able to hire a PhD student to further characterize this new population of macrophages and study their behavior, origin and function in more detail. Together with his colleagues, he will also explore the therapeutical potential of these cells to combat vascular injuries, sepsis and leukemia. About the LSBR The Landsteiner Foundation for Blood Transfusion Research (Stichting voor Bloedtransfusie Research, LSBR) is an independent foundation that uses the revenues of its assets to support fundamental research, including clinical and experimental investigations, in the field of blood, blood derivatives, and diseases related to transfusion or blood cell transplantation.