Mapping the accumulation of co-infiltrating CNS dendritic cells and encephalitogenic T cells during EAE

- BMDCs and T cells accumulate and interact in specific brain regions in early EAE.
- DCs and T cells accumulate in periventricular brain tissues before spinal cord.
- Immune cell migration through RMS is increased during neuroinflammation.
- We identify primary and secondary CNS compartments of immune cell entry in EAE.

Evidence from experimental autoimmune encephalomyelitis (EAE) suggests that CNS-infiltrating dendritic cells (DCs) are crucial for restimulation of coinfiltrating T cells. Here we systematically quantified and visualized the distribution and interaction of CNS DCs and T cells during EAE. We report marked periventricular accumulation of DCs and myelin-specific T cells during EAE disease onset prior to accumulation in the spinal cord, indicating that the choroid plexus-CSF axis is a CNS entry portal. Moreover, despite emphasis on spinal cord inflammation in EAE and in correspondence with MS pathology, inflammatory lesions containing interacting DCs and T cells are present in specific brain regions.