How Mycotoxins Trigger Mast Cell Activation and Brain Inflammation Mast cells are hypersensitive immune cells that release histamine and other inflammatory mediatorsoften in response to oxidative stress, environmental toxins, and immune imbalance. Many patients with MCAS have low levels of glutathione. Intestinal mast cellderived leukotrienes mediate the anaphylactic response to ingested antigens Science Diagnostic criteria of mast cell activation syndrome Download Scientific Diagram Mast cells are hypersensitive immune cells that release histamine and other inflammatory mediatorsoften in response to oxidative stress, environmental toxins, and immune imbalance. Many patients with MCAS have low levels of glutathione.