IL10 and Alzheimer disease: The involvement of local brain inflammation in AD pathogenesis55, with the failure of systemic immunosuppressive drugs to modify the disease in patients55,56, along with our previous studies showing that transient reduction of systemic FoxP3 regulatory T cells is needed for homing of regulatory cells to the diseased brain26, emphasize the need to distinguish between peripheral and local contributions of immunoregulatory cytokines, such as IL-10, in brain pathologies.