TTR and Alzheimer disease: For instance, macrophagemigration inhibitory factor (MIF) is a pro-inflammatory cytokine.Zhang and colleagues suggest that neuronal secretion of MIF may serveas a defense mechanism to compensate for declined cognitive functionin AD, and increased MIF level could be a potential AD biomarker.46 Transthyretin (TTR) has been described as anamyloid-β protein, preventing its deposition and toxicity.47 It has been suggested to transport proteinsover the blood brain barrier using LRP1. 48 The FAM3 superfamily member FAM3C ameliorates AD-like pathology by destabilizing theamyloid-β precursor.49