After a meal, insulin floods around the body helping our cells absorb excess sugar. This vital process starts in the pancreas where islets – clusters of endocrine cells – squirt the chemical out into the bloodstream. But how pancreatic cells first bunch together into islets is mysterious – cloudy fats in our organs make such events difficult to watch under a microscope. Peering inside a transparent zebrafish, though, reveals vital clues. As some of the pancreatic cells (red) naturally develop into insulin-producing beta cells (blue), researchers watch what happens next. The islet cells develop finger-like projections that reach out towards nearby neighbours. Later in development these may act as bridges, bringing pancreatic cells together and forming the islets. Further studies may help to replace or repair islets in human patients with type 1 diabetes, where these precious structures are often destroyed by the body’s own immune system.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.