First Author | Rosmalen JG | Year | 2000 |
Journal | Lab Invest | Volume | 80 |
Issue | 5 | Pages | 769-77 |
PubMed ID | 10830787 | Mgi Jnum | J:62250 |
Mgi Id | MGI:1858640 | Doi | 10.1038/labinvest.3780080 |
Citation | Rosmalen JG, et al. (2000) Islet abnormalities associated with an early influx of dendritic cells and macrophages in NOD and NODscid mice. Lab Invest 80(5):769-77 |
abstractText | In the nonobese diabetic (NOD) mouse model for type 1 diabetes, the inflammatory infiltration of islets starts with an influx of dendritic cells (DC) and macrophages (Mphi) at approximately 4 weeks of age. Around this time, NOD mice show endocrine abnormalities, indicated by a transient hyperinsulinemia that lasts until 8 weeks of age. Subsequently, they develop abnormally large islets of Langerhans, here designated as 'mega-islets.' NODscid mice, which lack functional lymphocytes, also exhibit transient hyperinsulinemia, but to a lesser extent. First, to determine the role of lymphocytes in the morphological islet abnormalities, we compared 6-week-old (prediabetic) NOD and NODscid females regarding mega-islet development and accumulation of antigen-presenting cells (APC), particularly CD11c+ DC and ERMP23+ Mphi. In NODscid mice, early APC infiltration and mega-islets were present, but less marked compared with NOD mice, thus suggesting a role of lymphocytes in mega-islet formation. In both NOD and NODscid mice, the APC infiltration was predominantly found around the mega-islets, suggesting a relationship between both parameters. Second, to analyze the role of beta-cell hyperactivity in mega-islet formation, we studied the effect of short-term prophylactic insulin treatment on these parameters. Prophylactic insulin treatment decreased the percentages of mega-islets in both NOD and NODscid mice, indicating that beta-cell hyperactivity is also involved in mega-islet formation. In conclusion, mega-islet formation in mice with the NOD genetic background takes place under the influence of both beta-cell hyperactivity and leukocytes. |