Researchers from VIB and Ghent University (UGent) have discovered a previously unknown cellular barrier in the brain, which fundamentally changes the scientific understanding of how the brain is protected from the rest of the body. In a study published in the journal Nature Neuroscience<\/i>, scientists revealed a new pathway through which the immune system can influence the brain.<\/p>\n
Until now, the blood-brain barrier and the choroid plexus (which produces cerebrospinal fluid) were considered the brain’s primary protective mechanisms. Using gene sequencing and high-resolution microscopy, researchers identified a unique population of cells they named “base barrier cells.” These cells are linked by tight junctions, which act as “molecular rivets,” creating an airtight seal between the brain’s fluid-filled spaces and the vascular core.<\/p>\n
The new protective mechanism discovered by VIB and Ghent University scientists is not static; it responds dynamically to changes within the body. In a healthy state, these “base barrier cells” form a hermetic shield via tight junctions, effectively restricting the movement of small molecules from the blood into the cerebrospinal fluid and brain tissue. This mechanism keeps the brain in an isolated, stable, and secure environment.<\/p>\n
The situation changes radically during systemic inflammation, such as when the body is fighting a severe infection. The study showed that during these periods, the barrier cells become vulnerable, weakening the protective “gate” and allowing harmful substances or foreign cells to penetrate the central nervous system. The discovery that this barrier also exists in the human brain provides scientists with a new target for treating neuroinflammatory diseases, offering the potential to strengthen this critical line of defense in the future.<\/p>\n
Importantly, these cells appear during the early stages of development and persist throughout life. Researchers confirmed their presence not only in mice but also in the human brain. According to the scientists, this discovery opens new avenues for studying neurological diseases and neuroinflammatory processes.<\/p>\n