Morphological and Ultrastructural Features of Human Islet Grafts Performed in Diabetic Nude Mice

• Published in: Ultrastructural pathology Vol. 29; no. 6; pp. 525 - 533
• Main Authors: Finzi, Giovanna, Davalli, Alberto, Placidi, Claudia, Usellini, Luciana, La Rosa, Stefano, Folli, Franco, Capella, Carlo
• Format: Journal Article
• Language: English
• Published: England Informa UK Ltd 01.11.2005; Taylor & Francis
• Subjects: Animals; Diabetes Mellitus, Experimental - surgery; Graft Rejection - pathology; Humans; islet transplantation; Islets of Langerhans - ultrastructure; Islets of Langerhans Transplantation; Mice; Mice, Nude; Microscopy, Electron, Transmission; type 1 diabetes; β cells degeneration
• ISSN: 0191-3123; 1521-0758
• DOI: 10.1080/01913120500323563

Islet transplantation is a new therapeutic approach to type 1 diabetes mellitus. However, in several patients insulin levels are not restored and the glycemic control is inadequate. To clarify the cause of graft failure, the authors investigated with light and electron microscopy some human islet grafts before and after transplantation under the kidney capsule of streptozotocin-induced diabetic nude mice. In isolated islets, both pre- and post-transplantation, the endocrine component was scarcely represented, the β/α cell ratio was reduced, and β cells showed degenerative aspects such as apoptosis, immature secretory granules, and amylin fibrils deposition. The authors conclude that islet graft failure may be due to an insufficent β cell mass related to their distress probably caused by anoxia and/or overstimulation.