Multiple,diverse senile plaque–associated proteins are ligands of an apolipoprotein e receptor,the α2-macroglobulin receptor/low-density-lipoprotein receptor—related protein |
| |
Authors: | G William Rebeck Steven D Harr Bradley T Hyman Dudley K Strickland |
| |
Abstract: | Both apolipoprotein E and its receptor, the low-density-lipoprotein receptor-related protein (LRP), are associated with senile plaques in Alzheimer's disease. We examined the relationship of other LRP-related molecules to senile plaques. LRP is a multifunctional receptor that blinds and rapidly internalizes at least seven ligands: apolipoprotein E, activated α2-macroglobulin, tissue and urokinase-type plasminogen activators, plasminogen activator inhibitor-1, lipoprotein lipase, and lactoferrin. Using immunohistochemistry, we showed that all of these ligands, representing a diverse group of otherwise apparently unrelated proteins, accumulate on senile plaques. We also studied expression of the receptor-associated protein, a physiological inhibitor of LRP, in the hippocampal formation from normal subjects and Alzheimer's disease patients. Receptor-associated protein colocalizes with LRP on neuronal soma, but not on neuronal processes or reactive astrocytes. It is not present on senile plaques. These results suggest that senile plaque-associated LRP can bind its ligands, but clearance of these compounds may be impaired in the vicinity of senile plaques. |
| |
Keywords: | |
|
|