The COVID – Mast Cell Activation Connection: Why Some People Never Fully Recover — section

Your immune system contains cells called mast cells. They live in every tissue in your body – gut lining, skin, lungs, brain vasculature, connective tissue. Their job is to be the first responders. When they detect a threat, they release a chemical arsenal: histamine, tryptase, prostaglandins, leukotrienes, cytokines. This triggers inflammation that is supposed to be protective and short-lived.