Dr. Theoharides (AKA – “The Mast Cell Master”), “Mast cells are the “universal alarm cell” that starts the inflammatory cascade. They can be triggered by infection, allergens, environmental factors like pollution, or even emotional stress. Once that happens, mast cells set into motion a series of inflammatory reactions, including the activation of immune cells and the release of tumor necrosis factor-alpha (TNF-alpha), a pro-inflammatory protein, or cytokine.”
Mast cells store chemical mediators in storage granules within the cell. These mediators include histamine, leukotrienes, prostaglandins, heparin, TNF-alpha, IL-4, IL-15 enzymes, proteases, and hormones such as serotonin and dopamine. This means that the mast cells can have effects on many different types of tissue, and in many types of bodily reactions to the release of those chemicals.
Mast cell granule contents are released through a process called degranulation. Activation through stimulation of the mast cell with specific triggers causes the the cell to release the stored contents through degranulation. The chemicals released by the mast cells cause the symptoms seen in mast cell reactions, such as flushing, swelling, itching, trouble breathing, etc. Because the mast cells contain so many different mediators, the symptoms will depend on what chemical is released, and where. When activated, a mast cell can either selectively release mediators or rapidly release a less selective group of mediators.
Mast cells are unique in that they are able to regranulate after the release of mediators, so they can cause reactions more than one time.
In Mast Cell Activation Syndrome, it is believed that the mast cells become overly activated in response to triggers, thereby releasing more chemicals than is usual in the healthy individual. It is not yet known why this happens, but it is believed that infections (including Lyme disease) or other chronic stressors may cause the hypersensitivity to stimuli.