GGA3 and Alzheimer disease: Therapeutic potential was evaluated by inhibiting the paired immunoglobulin-like receptor B (PirB) cleavage and overexpression of the GAT domain of Golgi-associated, gamma adaptin ear-containing, ARF binding protein 3 (GGA3).<h4>Results</h4>This study identified a pathogenic proteolytic pathway in AD patients and mouse models, which cleaves PirB, a mouse ortholog of human leukocyte immunoglobulin-like receptor B2 (LILRB2), upon Aβ exposure, generating a C-terminal fragment (PirB-CTF) that accumulated in the Golgi apparatus via retrograde transport.