28 March 2017 Thesis defence Léon van Gurp Back to news Today, Léon van Gurp from the De Koning group will defend his thesis titled “Characterisation of islet cells during development & after transplantation”. In this thesis, van Gurp describes the use of novel techniques with the purpose to better understand the development of pancreatic islet cells from stem cells, and how islets engraft after transplantation. He also developed a new technique that allowed intravital imaging of pancreatic tissue under the kidney capsule. The study showed that this technique could be applied to study pancreatic islet engraftment, and development of embryonic pancreases into grafts containing mature islets of Langerhans. This way, dynamic processes like cellular migration during islet cell development could be studied in vivo for the first time. Van Gurp also generated a resource of transcriptomic profiles from single cells of the pancreas during the secondary transitional phase of embryonic development. During this phase, progenitor populations are designated in specific domains and islet cells neogenesis peaks. This resource allows the detection of tissue heterogeneity in the embryonic pancreas. Novel genes involved in endocrine differentiation could be detected, and the study also characterized how genes were dynamically regulated during this developmental process. Finally, he also described a novel technique that allows printing of pancreatic islets into alginate scaffolds. Multiple alginate mixtures were compared, and islets were printed in both bulk and 3D porous scaffolds. The viability of the transplanted islets was confirmed, after which the scaffolds were transplanted subcutaneously in mice.