The cyan fluorescent protein (CFP) transgenic mouse as a model for imaging pancreatic exocrine cells.
BACKGROUND
The use of fluorescent proteins for in vivo imaging has opened many new areas of research. Among the important advances in the field have been the development of transgenic mice expressing various fluorescent proteins.


OBJECTIVE
To report whole-body and organ-specific fluorescence imaging to characterize the transgenic cyan fluorescent protein mouse.


METHODS
Mice were imaged using two devices. Brightfield images were obtained with the OV100 Small Animal Imaging System (Olympus Corp., Tokyo, Japan). Fluorescence imaging was performed under the cyan fluorescent protein filter using the iBox Small Animal Imaging System (UVP, Upland, CA, USA).


METHODS
All animals were sacrificed immediately before imaging. They were imaged before and throughout multiple steps of a complete necropsy. Harvested organs were also imaged with both devices. Selected organs were then frozen and processed for histology, fluorescence microscopy, and H&E staining. Fluorescence microscopy was performed with an Olympus IMT-2 inverted fluorescence microscope.


METHODS
Determination of fluorescence intensity of different organs.


RESULTS
Surprisingly, we found that there is differential enhancement of fluorescence among organs; most notably, the pancreas stands out from the rest of the gastrointestinal tract, displaying the strongest fluorescence of all organs in the mouse. Fluorescence microscopy demonstrated that the cyan fluorescent protein fluorescence resided in the acinar cells of the pancreas and not the islet cells.


CONCLUSIONS
The cyan fluorescent protein mouse should lead to a deeper understanding of pancreatic function and pathology, including cancer.
Tran Cao
Hop S
HS
Department of Surgery, University of California, San Diego, CA, USA.
Kimura
Hiroaki
H
Kaushal
Sharmeela
S
Snyder
Cynthia S
CS
Reynoso
Jose
J
Hoffman
Robert M
RM
Bouvet
Michael
M
D000818:Animals; D041981:Gastrointestinal Tract / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism*; D006651:Histocytochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000379:methods*; D023421:Models, Animal; D046790:Pancreas, Exocrine / Q000166:cytology / Q000378:metabolism*
C485182:Cyan Fluorescent Protein; D049452:Green Fluorescent Proteins