title: A dual-color genetically engineered mouse model for multispectral imaging of the pancreatic microenvironment.
abstract: OBJECTIVE
  To develop a mouse model for multispectral fluorescence imaging of the pancreas and pancreatic microenvironment.
  
  
  METHODS
  Cre/loxP technology was used to develop this model. We crossed mT/mG indicator mice, engineered to constitutively express a conditional tdTomato transgene that converts to green fluorescent protein (GFP) expression after exposure to Cre recombinase, with Pdx1-Cre transgenic mice. To characterize this model for studies of pancreas biology, we performed bright light and fluorescence imaging of body cavities and intact organs and confocal microscopy of pancreata from offspring of Pdx1-Cre and mT/mG crosses.
  
  
  RESULTS
  Pdx1-Cre-mT/mG mice demonstrated bright GFP expression within the pancreas and duodenum and intense tdTomato expression in all other organs. Green fluorescent protein expression was mosaic in Pdx1-Cre-mT/mG pancreata, with most showing extensive conversion from tdTomato to GFP expression within the epithelial-derived elements of the pancreatic parenchyma. Because both GFP and tdTomato are membrane targeted, individual cell borders were clearly outlined in confocal images of mT/mG pancreata.
  
  
  CONCLUSIONS
  This mouse model enables multispectral fluorescence imaging of individual cells and cell processes at the microscopic level of the pancreatic microenvironment; it should prove valuable for a variety of fluorescence imaging studies, ranging from pancreatic development to pancreatic cancer biology.
authors: Department of Surgery, UCSD Moores Cancer Center, La Jolla, CA 92093-0987, USA.
authors: Cynthia S
authors: CS
authors: Snyder
authors: Austin R
authors: AR
authors: Harrington
authors: Sharmeela
authors: S
authors: Kaushal
authors: Evangeline
authors: E
authors: Mose
authors: Andrew M
authors: AM
authors: Lowy
authors: Robert M
authors: RM
authors: Hoffman
authors: Michael
authors: M
authors: Bouvet
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods; D004195:Disease Models, Animal; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D019426:Integrases / Q000235:genetics / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018613:Microscopy, Confocal; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D059016:Tumor Microenvironment; D000097573:Red Fluorescent Protein
chemical_list: D049452:Green Fluorescent Proteins; D018398:Homeodomain Proteins; D019426:Integrases; D008164:Luminescent Proteins; D010940:Plant Proteins; D015534:Trans-Activators; D000097573:Red Fluorescent Protein; C084010:pancreatic and duodenal homeobox 1 protein; C045073:Cre recombinase
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