NK Cell Missing-Self Recognition — Signal-Space Map

Natural killer cells decide, target by target, whether to kill by weighing an inhibitory MHC-I signal against an activating stress-ligand signal. Rather than a rendered field of tissue, this view plots the whole target population directly in the two-dimensional space of those signals: MHC-I on one axis, stress ligand on the other. A straight decision-boundary line — the same rheostat rule the biology uses — separates the plane into a kill zone and a spare zone, and NK scanner agents sweep across this signal-space map, docking on the nearest cell and reading off its verdict. Downregulate MHC-I across the population, or carve out an infected patch, and watch points slide across the line: missing-self recognition made visible as pure geometry.