mastcelactivatie

Mast cell activation refers to the process by which mast cells release various potent chemical mediators. These mediators include histamine, proteases, cytokines, and prostaglandins. Mast cells are a type of immune cell found in connective tissues throughout the body, particularly near blood vessels, nerves, and in the skin, lungs, and digestive tract. They play a crucial role in allergic reactions and defense against pathogens, but their overactivity can lead to a range of symptoms.

The activation of mast cells can be triggered by a variety of stimuli. In allergic reactions, this is typically an allergen, such as pollen, dust mites, or certain foods, which binds to IgE antibodies on the mast cell surface. This binding triggers a cascade of events leading to degranulation and mediator release. Other triggers can include certain medications, physical stimuli like heat or cold, stress, and even infections.

When mast cells degranulate, the released mediators cause a variety of effects in the surrounding tissues. Histamine, for instance, increases blood vessel permeability, leading to swelling and redness, and can cause itching and smooth muscle contraction. Other mediators contribute to inflammation, pain, and can affect various organ systems.

Disorders characterized by inappropriate or excessive mast cell activation are known as mast cell activation disorders. These can include mastocytosis, where there is an accumulation of mast cells in tissues, and mast cell activation syndrome, where mast cells are present in normal numbers but are overly reactive. Symptoms can be systemic and diverse, affecting the skin, gastrointestinal tract, respiratory system, cardiovascular system, and nervous system. Diagnosis often involves a combination of clinical evaluation, symptom tracking, and laboratory tests.