|July 24, 2012|
Noninvasive Imaging of β Cells in Diabetic Mice
Need to monitor and identify insulin-producing β cells in mouse models of type 1 or 2 diabetes? Consider either the C57BL/6-Tg(Ins2-luc/EGFP/TK)300Kauf/J (012943) or the NOD.B6-Tg(Ins2-luc/EGFP/TK)300Kauf/J (013116) strains.
Both strains harbor the commonly called “MIP-TF” tri-fusion transgene, which consists of three imaging reporters – insulin 2 luciferase (Ins2-luc), enhanced green fluorescent protein (EGFP), and thymidine kinase (Tk) – all controlled by the mouse Ins2 promoter. Signals from the pancreatic regions of both models can be detected with a cooled charge coupled device (CCD) and/or micro positron emission tomography (microPET). The signals are correlated and can be used to non-invasively image pancreatic β cells in the same mouse. Fluorescence microscopy can be used to identify the very same cells histologically.
When type 1 diabetes (with concomitant hyperglycemia and destruction of pancreatic beta cells) is streptozotocin-induced in the model with the C57BL/6 background, bioluminescence signals from the pancreas decrease. Conversely, those signals nearly quadruple if this strain is instead fed a high fat diet to model early type 2 diabetes.
The first model was constructed and donated to our repository by Daniel Kaufman (Yong et al. 2011), UCLA School of Medicine. To construct the second model, the Type 1 Diabetes Resource backcrossed the first one onto the NOD background, producing a strain that spontaneously develops type 1 diabetes.