A team led by Professor Nicholas Barnes at the University of Birmingham has identified a receptor called P2X7 as a trigger of inflammatory signaling in human brain cells, and showed that blocking it with an existing experimental compound sharply reduced that signaling in donated human brain tissue. The findings, published online February 19, 2026 in the journal Brain and appearing in print in the journal's October 2026 issue, are described by the university as a step toward repurposing existing drugs for Alzheimer's disease and other conditions linked to brain inflammation.
The researchers worked with two human models rather than animals alone. They first converted monocytes taken from blood samples into microglia-like cells, the brain's resident immune cells, and primed them to mimic an inflammatory state. Adding a compound that activates P2X7 caused these cells to release the inflammatory proteins interleukin-1 beta and interleukin-18; adding a P2X7-blocking compound, including one called A-804598, reduced that release. The team then repeated comparable tests on slices of human brain tissue obtained during neurosurgical procedures, and reported that blocking P2X7 again reduced the inflammatory response, data the authors say shows the effect translates from isolated cells to intact human brain tissue.
The study did not test the compound in people, and the brain tissue and blood samples used were not reported as coming from patients with Alzheimer's disease; the link to Alzheimer's rests on P2X7's known role in neuroinflammation in that disease and others, including Parkinson's disease and traumatic brain injury, rather than on a direct test in affected patients. Barnes said the next step is the development of clinical trials in people with neurodegenerative conditions and traumatic brain injury, which indicates that human efficacy and safety testing has not yet begun.