Bone Marrow-Derived Cells Fuse with Bergmann Glia in Experimental Autoimmune Encephalomyelitis

Abstract

Bone marrow-derived cells (BMDCs) can infiltrate the brain and adopt new identities through transdifferentiation or fusion, yet their interactions with specific neural cells remain poorly defined. We examined BMDC fusion with Bergmann glia (BG), a key cerebellar support cell, in a mouse model of multiple sclerosis. After bone marrow transplantation, BMDCs fused with BG to form heterokaryons, retaining BG morphology and molecular markers. These heterokaryons contained donor and host nuclei that differed in both morphology and transcriptional activity. Remarkably, the BMDC nucleus localized not only to the soma but also along BG processes. This discovery identifies BMDC-BG fusion as a previously unrecognized form of glial plasticity, opening avenues for therapeutic strategies aimed at potentiating glial-mediated repair.