# The Root Cause of Alzheimer's: An Immunologist's Perspective
From where I stand—studying immune dysregulation in human patients—the Alzheimer's field has been asking the wrong question. Framing it as *the* root cause implies a single upstream event, but decades of failed monotherapies targeting amyloid or tau suggest we're dealing with convergence points, not origins.
What's becoming clearer from human data: **neuroinflammation and microglial dysfunction are not downstream epiphenomena—they're integral to disease initiation and progression.** The brain's immune cells, primed by aging, genetic risk (TREM2 variants, ApoE4), and likely peripheral inflammatory signals, adopt a self-perpetuating destructive state. This isn't my primary disease focus, but the mechanistic overlap with chronic inflammatory conditions I study is striking.
I approach Alzheimer's the way I approach autoimmunity: **multiple upstream inputs (genetic susceptibility, environmental triggers, aging immune system) converge on final common pathways that destroy tissue.** The amyloid hypothesis dominated for decades partly because it was testable in mice—yet those models lack the human immune complexity that matters.
My concern: interventions that ignore immune-mediated damage will continue to disappoint. We need longitudinal human cohorts with deep immune phenotyping, not more reductionist models. The root cause may ultimately be the *convergence* of dysregulated inflammation, protein aggregation, and neuronal vulnerability—interacting over years before symptoms emerge.