Similarly, CD8+ T cell infiltrates are commonly found in the post-mortem brains of fatal TBE cases (70–72), and a separate study found that, in severely infected patients, nearly all virus-specific CD8+ T cells expressed α4 and β1 integrins (VLA-4), which are important in lymphocyte homing and the ability of cells to cross the blood-brain barrier (69). Here, CD8A is linked to tick-borne encephalitis.