Researchers at Washington University School of Medicine discovered previously unknown immune structures inside the skull bone marrow of mice that act as rapid-response defense stations against brain cancer. These structures resemble lymph nodes and become active against glioblastoma before more distant lymph nodes receive any signal. Proteins traveling from the brain through tiny skull channels trigger these local immune hubs, which then coordinate T and B cell responses, including antibody production. Strengthening this local defense improved tumor rejection and survival in mice. Human skull bone marrow showed similar immune cells, suggesting the system may translate to people. The findings reframe how scientists understand brain-immune communication and open a potential new avenue for treating brain tumors by targeting the skull directly.
