ABCC5 and Alzheimer disease: Although no reports were found of alterations of ABCC5 expression or activity in AD brain, the possibility that the ability of ABCC5 to prevent entrance of blood-borne Aβ into the brain may be impaired in AD was suggested by a study in which ABCC5 transporter activity was decreased after exposure of PBECs to Aβ42 (Shubbar and Penny, 2018).