MAPT and Alzheimer disease: PNT001 is a human IgG4 monoclonal antibody that targets the cis-isomer of phosphorylated tau at threonine 231 (cis-pT231), a form of pathological tau that increases significantly after traumatic brain injury (TBI) [188] and also identified in brain tissues of patients with AD, vascular dementia, and CTE [189].