Figure 1. Autoimmunity after stroke.

Left to right: In response to stroke antigenic material exits the CNS and is taken up by dendritic cells in cervical lymph nodes. Macrophages from the periphery also migrate to the damaged tissue to participate in the clearance of dead cells and cellular debris. We propose that a subset of these phagocytic cells exit the brain via the meningeal lymphatic system and also reach the cervical lymph nodes. Here they come into contact with, and present antigen to, autoreactive B- and T-lymphocytes that have escaped negative selection. Once activated, autoreactive B-lymphocytes proliferate, secrete antibody into the circulation, and home to the infarct. Within the infarct they encounter additional antigen resulting in the further production of autoantibodies within the CNS compartment. Finally, neurodegeneration may occur and contribute to post-stroke cognitive decline and dementia.