NEUROFIBRILLARY TANGLES OF ALZHEIMERS-DISEASE BRAINS CONTAIN 14-3-3 PROTEINS

The localisation of 14-3-3 proteins compared to that of tau acid ubiqu itin-protein conjugates in sections of hippocampus from Alzheimer's di sease (AD) brains was examined by immunohistochemistry. In all cases ( n = 10), anti-14-3-3 stained a proportion of neurofibrillary tangles ( NFT). In general, NFT stained by anti-14-3-3 were smaller than those s tained by anti-tau or anti-ubiquitin-protein conjugates and were more confined to the neuronal cell body. Occasionally, cortical Lewy bodies in cases of Lewy body dementia were also found to be 14-3-3-positive. Since 14-3-3 proteins are central to MAP kinase signalling, the resul ts support the proposal that this pathway is in part responsible for t he hyperphosphorylation of tau, which leads to the formation of the pa ired helical filaments seen in AD brains.