Increased cGAS/STING signaling components in patients with Mooren’s ulcer
Authors:   Xi&#x2019;an Children&#x2019;s Hospital, Xi&#x2019;an 710004, Shaanxi Province, China; Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Zhang Ya-Ni , Hao Wen-Pei ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Bai Xiao-Fei ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Qi Xia ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Liu Ting ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Sun Xiao-Tong ,   Qingdao Eye Hospital of Shandong First Medical University, Qingdao 266071, Shandong Province, China, Wei Chao ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Qi Xiao-Lin ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China; Eye Hospital of Shandong First Medical University, Jinan 250021, Shandong Province, China
Published: October 2021

AIM: To explore the expression of cGAS/STING signaling components in Mooren’s ulcer (MU).
METHODS: Samples were obtained from ten MU patients, and eight residual corneal-scleral rings of healthy donor corneas for controls. Human corneal epithelial cells (HCECs) were used to evaluate the effect of cGAS/STING signaling pathway. Immunohistochemistry (IHC) and Western blot were used to examine the expression of cGAS, STING, and phosphorylated interferon regulatory factor 3 (p-IRF3) in MU tissues. The expression of interferon-β (IFN-β) and interferon-stimulated genes (ISGs) was quantified by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA).
RESULTS: The protein levels of cGAS and STING in MU samples were significantly elevated when compared with the healthy controls by Western blot and IHC. After stimulation with cGAMP, real-time PCR and ELISA showed a dramatic increase of IFN-β and ISGs (containing CXCL10, IFIT1, and IL-6) in HCECs. Moreover, HCECs treated with cGAMP was characterized by increased phosphorylation and more nuclear translocation of IRF3. Meanwhile, increased p-IRF3 was observed in MU samples via IHC and Western blot.
CONCLUSION: The pronounced expression of cGAS/STING signaling components in the patients with MU and probably contribute to the onset and development of MU.