Intravital Imaging: A Method for Cellular Level Observation of the Mouse Pancreas Through a Stabilized Imaging Window

Intravital imaging involves visualizing cells of a live animal through an imaging window implanted into the animal. It enables long-term observation of cellular dynamics without compromising their functions.

To begin, take an anesthetized transgenic mouse previously implanted with a pancreatic imaging window supported on a metal plate. The base plate spatially separates the pancreas from the bowel, thereby reducing motion artifacts from physiological movements such as peristalsis.

The transgenic mouse expresses green fluorescent protein or GFP under insulin gene promoter expressed in beta cells of islets in the pancreas.

Next, hold the mouse tail firmly and spray disinfectant to remove any surface contaminants. Insert a catheter into the lateral tail vein. Inject a solution containing antibodies tagged with a red fluorescent probe into the tail vein. These antibodies bind to the cells lining the blood vessels, staining them red.

Now, shift the mouse to an intravital microscopy setup. Insert the pancreatic imaging window into the window holder. Start imaging under low magnification to locate green fluorescing islet clusters surrounded by red fluorescing blood vessels. Increase the magnification to obtain high-quality cellular level imaging of individual beta cells.