CD8 T cells as drivers of blood-brain barrier disruption

Blood-brain barrier (BBB) disruption is a hallmark of many neurological diseases. It is known that proinflammatory cytokines can disrupt tight junctions between endothelial cells of the BBB, allowing larger molecules to penetrate the brain. Along with BBB disruption, these diseases also feature increased numbers of CD8 T cells as components of the immune cell population in the brain. In this review, we discuss the mechanisms of CD8 T cell-mediated BBB disruption, including the roles of antigen presentation through MHC class I molecules, which emerge as an important determining feature of BBB disruption and immune cell infiltration into the brain.