Progranulin and beta-amyloid distribution: a case report of the brain from preclinical PS-1 mutation carrier.

BACKGROUND: Progranulin (PGRN) is a multifunctional growth factor that is found in many tissues. Mutations in the PGRN gene cause familial frontotemporal dementia with ubiquitin-positive inclusions. PGRN plaque-like structures have been described in Alzheimer's disease (AD), in association with beta-amyloid (Abeta) plaques. OBJECTIVE: To investigate PGRN and aggregated Abeta immunolabeling distribution in autopsied brain tissue from the participant with confirmed PS-1 (A246E) mutation, who died prior to clinical symptom onset. RESULTS: Immunolabeling for PGRN was positive and accumulated/formed plaque-like structures in all studied regions. These structures most frequently colocalized with Abeta though there were some that did not. PGRN plaques were most dense in medial temporal and frontal regions and predominated over aggregated Abeta. CONCLUSIONS: This case report illustrates PGRN accumulation and Abeta aggregation in preclinical PS-1 AD case and raises the question whether this phenomenon coincides with or precedes Abeta aggregation.