In 1100BC, we followed a grumpy man with a poisonous snake on a stick into the desert till it triggered an immune response. In 400AD, we collected dried skin flakes from the cold sores of an old woman and snorted them up our nostrils to trigger an immune response. In the 1400’s, wax and feces collected from the soggy crack of a horse hoof was injected under the skin to trigger an immune response. By the sixteenth century, we were pricking witches with metal prongs to trigger a village-wide immune response. The witch supply collapsed fifty years later so we harvested the pus from the ass of a traveling cow and smeared it into the freshly opened sores of children sequestered in a barn. That triggered an immune response. In the 18th century we were mixing mercury and spit into silly putty and coating our wounds to stimulate an immune response. A hundred years later we started scraping the dusty green mold from the surface of an orange and freebasing it into our lungs to trigger an immune response. Today, we inject aluminum from the finest corporate logos endowed with a blank insert and the steady hands of a masked-zombie wearing scrubs.
The primary function of the immune system is to distinguish self from all that is not. That wasn’t a metaphysical sentence. The body has a very simple immigration policy. The mechanics of inflammation knows who you are and who you are not. At least it’s supposed to. The TSA we call phagocytosis isn’t perfect because you are a living god who is intentionally hackable. You command a microcosm of dancing nurses with your own CIA. You manipulate your cellular population with a myriad of puppet dictators in a wide variety of attempts to stimulate an immune response. Face it, you have no idea what you’re doing down there and if the people inside you knew it you’d be gone. All of us are playing God.