Tau protein and Alzheimer's disease

The etiology of Alzheimer's disease is still unknown. Because the disease is specific for human brain, a rational search for early diagnosis or prevention is very difficult. This calls for the development of cellular models that mimick the degeneration of neurons in AD. The brains of AD patients contain markers whose composition and location is characteristic of the disease; one of the most reliable markers is tau protein in its pathologically phosphorylated and aggregated form. This form of tau can serve as a guide to the origins of the pathology. One goal of research that should be feasible within the near future is to construct a cell that induces the same abnormal changes in tau protein in response to defined stimuli (extracellular signals, toxins, stress, etc.). This model can then be used to identify possible substances that might cause the disease, or identify strategies for preventing it. Once they are defined on a cellular level, the next step would be to test them on (transgenic) animal models which are being developed at present.