Regional distribution of cortical microglia parallels that of neurofibrillary tangles in Alzheimer's disease

It has been postulated that microglia contribute to the development of neur ofibrillary tangles (NFT) in Alzheimer's disease (AD). We compared the dist ribution of microglia with that of NTT in both AD and non-AD cases. In AD c ases, we found that the extent of area covered by Ricinus communic agglutin in-1 labeled microglia generally paralleled NFT frequency and distribution. Microglia occupied the greatest area in tangle-rich periallocortex/allocor tex, a lesser area in association cortex, and the smallest area in tangle-p oor primary cortex. Interestingly, this pattern was also present in non-AD cases where there were few to no NFT. These findings suggest that regional variations in microglial distribution may constitute, at least in part, a t emplate for the development of NFT. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.