Allergic mediators released from mast cells
Antigens can cause degranulation of mast cells resulting in allergic reactions. Some of the allergic mediators released from mast cells are preformed whereas others are synthesised on demand.
| Preformed mediators | |
|---|---|
| ECF-A | Eosinophil chemotactic factor of Anaphylaxis – attracts eosinophils to the site |
| NCF – A | Neutrophil chemotactic factor – attracts neutrophils to the site |
| Histamine | Vasodilation and bronchospasm |
| Heparin | Promotes phagocytosis |
| Newly synthesised mediators | |
| Prostaglandin | Vasoconstriction and bronchospasm |
| Leukotriene | Vasoconstriction and bronchospasm |
| Thromboxane A2 | Vasoconstriction and platelet aggregation |
| PAF | Platelet Activating Factor – bronchospasm, platelet aggregation, chemotaxis of neutrophils, eosinophils |
| TNF alpha | Tumour necrosis factor – transmigration of eosinophils and neutrophils |
