After 3 months (once every 5 days) of intraperitoneal injection of anti-CD19/B220 antibodies, neurobehavioral tests were performed at the 28th week, and immunohistochemical staining was performed at the 30th week, which revealed that AD mice with B cell inactivation suffered much more severe cognitive deficits than AD controls. This evidence concerns the gene CD19 and Cognitive impairment.