A strategy for identifying immunosuppressive therapies for Alzheimer disease

There is increasing evidence that the immune system plays an important role in the pathology of Alzheimer disease (AD). The fundamental steps in this process involve induction of neurotoxic microglia by senile plaques. Recent studies have shown that microglia in contact with isolated plaque fragments secrete neurotoxins that can cause neuronal injury and brain damage typical of AD. In vitro models help to delineate individual steps of this activation cascade by which quiescent microglia become neuron-killing cells. Moreover, such model systems provide rapid screening assays to identify immunosuppressive drugs that might slow brain damage brought on by neurotoxic microglia.