Duration 5min, Q&A 3min
Histopathological Observation of Ocular Surface in Sjögren's Syndrome Mouse Model : C57BL/6.NOD-Aec1Aec2 Mouse
To investigate the histopathological changes of the Sjögren's syndrome mouse model: C57BL/6.NOD-Aec1Aec2 mouse and to make sure whether it could develop dry eye disease spontaneously and to analyze the mechanism of the SS model.
Forty C57BL/6.NOD-Aec1Aec2 mice and twenty C57BL/6J mice (both male and female) were used in our study.
Forty C57BL/6.NOD-Aec1Aec2 mice and twenty C57BL/6J mice (both male and female) were used in our study. Fasting blood-glucose, Schirmer's test and fluorescein staining of corneal epithelium were performed at the age of the fourth, the eighth, the twelfth, the sixteenth, and the twentieth week of C57BL/6.NOD-Aec1Aec2 mouse and the fourth, the eighth, the twelfth, the sixteenth, and the twentieth week of C57BL/6J mouse orderly. Four mice were killed randomly to measure the thickness of central cornel epithelium and the number of conjunctival goblet cells at each time point. Lymphocyte infiltrations into the lacrimal gland were observed with hematoxylin and eosin (HE) staining. Additionally, cornel epithelial cell and microvilli were also assessed under scanning electron microscopy at each time point. Lastly, the expression of IL-17 and FOXP3+ in the lacrimal gland was determined by immunohistochemistry and semi-quantitative PCR.
Results and Conclusion
Both the C57BL/6.NOD-Aec1Aec2 mouse and C57BL/6J mouse didn't show any sign of dry eye disease and there were no variance between them at the fourth week (P>0.05). Decreased tear secreting, increased grade of corneal fluorescein staining, thin of corneal epithelium, reduced number of conjunctival goblet cells and increased lymphocyte cells in the lacrimal gland were observed with aging of C57BL/6.NOD-Aec1Aec2 mouse. Corneal epithelial cells dropped and microvilli diminished with aging were observed under scan electron microscopy. And relative expression of IL-17 in the lacrimal gland increased at the beginning of the eighth week, up to the peak at age of the twelfth week and then dropped at the age of twentieth week, while FOXP3+ in the lacrimal gland kept stable increase till twentieth week. The C57BL/6J mouse didn't show any sign of dry eye disease at all the time points. Interestingly, the fasting blood-glucose of the two type of mouse at each time point is less than 6.0mmol/L and there is no variance between the two groups all the time.
C57BL/6.NOD-Aec1Aec2 mouse could develop dry eye disease and mimic the onset and development of Sjögren's syndrome spontaneously. Inflammation due to increased IL-17 and unbalance between IL-17 and Treg cell in the lacrimal gland may be a potential reason for dryness of the mouse.
[ Keyword ]
Sjögren's syndrome (SS); dry eye disease (DED); C57BL/6J mouse; C57BL/6.NOD-Aec1Aec2 mouse; inflammation; histopathology.
[ Conflict of Interest ]