IMMUNE SYSTEM

The immune system is an unprecedented concept in modern medicine. Unlike the cardiovascular, gastrointestinal, or neurological systems—which traditionally refer to discrete sets of structures in particular parts of the body—the immune system describes a function throughout the body. It includes the lymph, which courses through vessels that connect the nodes throughout us, and the spleen, which also filters blood and creates antibodies that lead to long-lasting immunity— an ability of our blood to “remember” certain infections and not fall prey to them again. The immune system is also our bones, which produce the blood that remembers and ingests and ignores compounds accordingly. Blood cells act by causing inflammation and oxidation, and by neutralizing inflammation and the products of oxidation. The immune system is the linings of our mouths, throats, lungs, stomachs, and bowels—everywhere that comes into contact with the outside world, and all the cells secreted on those surfaces that can consume and destroy certain substances while harboring others. The immune system is in the skin, not just as the physical barrier to keep pathogens out, but as an active organ secreting molecules that harbor a population of skin microbes that themselves protect us from disease-causing infection.