Researchers at Washington University School of Medicine in St. Louis have engineered a cellular immunotherapy that cleared half the amyloid plaque from the brains of mice after a single injection. When the treatment was given before plaques had begun to form, it prevented them from developing at all. The team says this is the first time astrocytes, a type of brain cell, have been successfully engineered to seek out and remove amyloid beta plaques in mice with Alzheimer's disease.
The design borrows from CAR-T therapy in cancer, where a patient's T cells are genetically modified with a chimeric antigen receptor that acts as a homing device, locking onto a target so it can be destroyed. Here the modified cells are astrocytes rather than T cells, and the target is amyloid. The researchers describe the altered cells as super cleaners, capable of stripping out damaging proteins tied to cognitive decline.
The practical appeal is in the dosing. The monoclonal antibody drugs now approved for Alzheimer's are the first treatments shown to alter the course of the disease, buying patients roughly 10 months of additional independent living, but they demand high-dose infusions once or twice a month indefinitely. A one-time cellular treatment would spare patients and caregivers that ongoing burden, and the researchers hope it could also prove more effective at clearing amyloid.
This remains mouse work. The team acknowledges that the approach needs optimization and that potential side effects have yet to be worked out before anything like it could be tested in people. If those hurdles can be cleared, the researchers see CAR-astrocytes as a platform with reach beyond Alzheimer's, into other neurodegenerative diseases and possibly brain tumors.