Cancer Breakthrough Inspires New Alzheimer’s Treatment Strategy, Harvard Study Finds

A groundbreaking study reported by The Harvard Gazette reveals that a cancer-fighting immune strategy may offer new hope for Alzheimer’s disease. Researchers at Harvard Medical School and Brigham and Women’s Hospital found that disabling a key immune system “checkpoint” molecule called TIM-3 improved memory and reduced toxic plaques in mice—potentially opening the door to a new kind of Alzheimer’s therapy.

The findings, published earlier this month in Nature, were discussed in an interview conducted by Harvard Gazette staff writer Alvin Powell with Dr. Vijay Kuchroo, senior author of the study and Samuel L. Wasserstrom Professor of Neurology at Harvard Medical School. Kuchroo and his team discovered that microglia—immune cells in the brain—stop clearing harmful plaque when the TIM-3 molecule is highly expressed. This buildup is a hallmark of Alzheimer’s.

“These microglia are supposed to clear amyloid beta plaques,” Kuchroo told the Gazette. “But when TIM-3 is overexpressed, they become homeostatic and ineffective.” In the study, mice genetically engineered without TIM-3 showed reduced plaque burden and significantly improved memory performance in behavioral tests.

Checkpoint molecules like TIM-3 are better known for their role in cancer, where they prevent immune cells from attacking tumors. Drugs that block these checkpoints have revolutionized cancer treatment—and now may offer similar benefits in neurological diseases.

Researchers believe TIM-3-targeted therapy could be less likely to cause harmful side effects than current Alzheimer’s drugs, which often damage blood vessels while trying to reach the brain. Because TIM-3 is selectively expressed on microglia rather than blood vessels, scientists are hopeful existing anti-TIM-3 antibodies developed for oncology could be repurposed for Alzheimer’s clinical trials.

The research, a five-year collaboration between Kuchroo and Dr. Oleg Butovsky of the Ann Romney Center for Neurological Disease, is now entering the next phase: testing humanized TIM-3 antibodies in genetically engineered mice. The study was funded in part by the National Institutes of Health.

As reported by The Harvard Gazette, the findings point to a powerful new tool in the fight against Alzheimer’s—one already battle-tested in oncology, but now with the potential to protect memory and brain health.