The question of where exactly in the body stem cells go after they’ve been injected has never been easier to answer, at least in a mouse.
BioInVision has developed an automated system combining a mouse-sized crytotome with a fluorescence (and bright-field) microscope, allowing fluorescently labeled stem cells to be visualized anywhere in the mouse with single-cell sensitivity. The CryoViz™ system will make 40 µm-thick serial cross-sections, “and then we have a microscope that is moved with a robot over the face of the tissue, getting microscopic images of basically the entire mouse,” said David Wilson, Ph.D., BioInVision’s CTO.
Researchers will use the system to look at the biodistribution of stem cells throughout the mouse. Or in the case of myocardial infarction, stem cells may be used to help treat the injury, and CryoViz will be used to evaluate the homing of cells to the infarcted region.
It takes about 15 hours to image an entire mouse. “The stem cell analysis is automated, and it will run by itself. The next day you can have the 3D images,” Dr. Wilson said. “Then if people want counts of cells in different organs, or densities, we have software to make those analyses as well.”
It can be used to image several fluorescent or quantum-dot reporters simultaneously, and it can be combined with vital imaging techniques such as MRI, PET, and bioluminescence. “We use advanced computer algorithms to do the registration … without the need to add extra fiducials (on the arms and legs, for example),” Dr. Wilson said.
The instrument can be purchased from BioInVision or used by means of a fee-for-imaging service, simply by shipping the company the frozen mouse. Using a tape-transfer technology, researchers can also pick up an entire section and treat the fresh-frozen, non-fixed tissue with a histology stain or labeled antibody for immunohistochemistry. “Say in a mouse we do this with 10 or 15 different sections. The advantage is that we know exactly where that section is within the 3D anatomy,” Dr. Wilson said.