18F-THK5351 tau PET imaging in Alzheimer's disease, frontotemporal.

Years before Alzheimer's disease becomes apparent in a patient, there are already changes in the brain, with increasing amyloid accumulation between the nerve cells. This abnormality can be measured with an amyloid PET brain scan, and is used to measure the effect of study drugs, e.g. immunotherapy. Insight into this amyloid accumulation and all that goes with it, before symptoms occur, is of great practical importance. In this study we want to determine how gene expression changes in individuals who are in the phase of amyloid increase. In the Laboratory for Cognitive Neurology we follow a group of normal elderly volunteers who were between 55 and 80 years old at the start of the study participation (between 2010 and 2015) and all scored within the normal limits in terms of memory, attention span, and word finding, and did not experience memory difficulties. At the start of the study, all participants underwent an amyloid PET scan, an MRI scan, and extensive neuropsychological research. The neuropsychological examination is repeated every two years. From 81 participants, a blood tube was also taken at time of inclusion to examine the RNA (gene expression). In this study we will carry out a second amyloid PET for these volunteers 3-6 years after the first amyloid PET scan, and take a a second RNA blood sample. We hypothesize that amyloid deposition will be accompanied by gene expression changes in networks that are related to the immune defense system. Changes in the immune system that are associated with changes in amyloid may also offer opportunities in the long term to develop treatments to influence the immune response.