Aβ vaccination effects on plaque pathology in the absence of encephalitis in Alzheimer disease

Abstract
The authors report a patient with Alzheimer disease (AD) without encephalitis who was immunized with AN-1792 (an adjuvanted formulation of Aβ-42). There were no amyloid plaques in the frontal cortex and abundant Aβ-immunoreactive macrophages, but tangles and amyloid angiopathy were present. The white matter appeared normal and minimal lymphocytic infiltration in the leptomeninges was observed. This case illustrates the effects of an Aβ-based immunization on AD pathogenesis in the absence of overt meningoencephalitis and leukoencephalopathy.