Scientists have discovered a potential strategy for developing treatments to stem the disease process in Alzheimer's disease. It's based on unclogging removal of toxic debris that accumulates in patients' brains, by blocking activity of a little-known regulator protein called CD33. Too much CD33 activity may promote late-onset Alzheimer's by preventing support cells from clearing out toxic plaques. Future medications that impede CD33 activity might help prevent or treat the disorder.