STING Signaling Deficiency Exacerbates Demyelination and Immune Infiltration in Focal EAE Lesions.

Stimulator of interferon genes (STING) is a cytosolic DNA sensor that activates type I interferon (IFN) signaling, which plays a key role in neuroinflammation. Although the role of STING in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS), remains debated, its involvement in the development of CNS lesions, particularly within localized pathology, modeled here by targeting the corpus callosum, has yet to be explored. Using a focal EAE model, we compared the induction of lesions in wild-type and STING-deficient (STING^gt/gt) mice. Lesions were analyzed by immunohistochemistry, flow cytometry, and transcriptomics. STING-deficient mice had significantly larger demyelinated lesions, reduced ISG expression, and modified immune cell infiltration. STING signaling limits lesion severity in focal EAE by promoting IFN responses and regulating immune infiltration. These findings position STING as a potential target for MS therapy.