Intravital imaging of DSS-induced cecal mucosal damage in GFP-transgenic mice using two-photon microscopy
Yuji Toiyama1, Akira Mizoguchi, Yoshinaga Okugawa
1Department of Gastrointestinal and Pediatric Surgery, Division of Reparative Medicine, Institute of Life Sciences, Mie University Graduate School of Medicine, Tsu, Mie, Japan. ytoi0725@clin.medic.mie-u.ac.jp
Background:
Two-photon laser-scanning microscopy (TPLSM) is a powerful diagnostic tool for real-time, high-resolution structural imaging. However, obtaining high-quality in vivo TPLSM images of intra-abdominal organs remains technically challenging.
Materials And Methods:
An organ-stabilizing system was applied to high-quality TPLSM imaging. Real-time imaging of visceral organs, such as the liver, spleen, kidney and intestine, of transgenic green fluorescent protein (GFP) mice was performed in vivo using TPLSM. The bacterial translocation model using dextran sodium sulfate (DSS)-induced colitis was also investigated in prepared GFP mice following simple surgery. This allowed the capture of morphological real images using in vivo TPLSM. Immunohistochemical analysis of ZO-1 was performed to support the morphological findings of TPLSM.
Results And Conclusions:
We established an organ-stabilizing system to evaluate the real-time imaging of visceral organs in actin-GFP transgenic mice using in vivo TPLSM. DSS-induced colitis showed irregularity of crypt architecture, disappearance of crypts, inflammatory cell infiltration and increased rolling of white blood cells along the vasculature. In addition, the intercellular distance of mucosal cells in the crypt and vascular endothelial cells in the intestinal wall was increased in the intestinal mucosa during DSS colitis. In DSS colitis, there was remarkable loss of mucosal and vascular endothelial ZO-1 expression, as could be seen by a decrease in ZO-1 staining. In conclusion, our observations suggested the possibility that our TPLSM imaging system can be used to clarify the pathophysiological changes in various diseases using longitudinal studies of microscopic changes in the same animal over long periods of time.
Insights
A new organ-stabilizing system enables high-quality in vivo two-photon laser-scanning microscopy (TPLSM) of visceral organs. This advanced imaging technique visualizes disease progression, such as in dextran sodium sulfate (DSS)-induced colitis models.
Area of Science:
- Biomedical Imaging
- Microscopy Techniques
- In Vivo Imaging
Background:
- Two-photon laser-scanning microscopy (TPLSM) offers high-resolution structural imaging.
- In vivo imaging of intra-abdominal organs using TPLSM presents significant technical challenges.
Purpose of the Study:
- To establish an organ-stabilizing system for high-quality in vivo TPLSM of visceral organs.
- To investigate the utility of this system in a dextran sodium sulfate (DSS)-induced colitis model.
Main Methods:
- Developed and applied an organ-stabilizing system for TPLSM.
- Performed real-time in vivo imaging of visceral organs (liver, spleen, kidney, intestine) in transgenic green fluorescent protein (GFP) mice.
- Utilized a bacterial translocation model with DSS-induced colitis in prepared GFP mice.
- Conducted immunohistochemical analysis of ZO-1 to correlate with morphological findings.
Main Results:
- The organ-stabilizing system facilitated high-quality TPLSM imaging of visceral organs.
- DSS-induced colitis exhibited irregular crypt architecture, crypt loss, inflammatory cell infiltration, and increased white blood cell rolling.
- Increased intercellular distances in mucosal and vascular endothelial cells were observed during DSS colitis.
- Significant loss of ZO-1 expression in mucosal and vascular endothelial cells was noted in DSS colitis.
Conclusions:
- An organ-stabilizing system was successfully established for in vivo TPLSM of visceral organs in actin-GFP transgenic mice.
- The system effectively visualized pathophysiological changes in DSS-induced colitis.
- This TPLSM imaging approach holds potential for longitudinal studies of microscopic changes in disease progression.
