Chemotaxis is a kind of taxis, in which bodily cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food (for example, glucose) by swimming towards the highest concentration of food molecules, or to flee from poisons (for example, phenol). In multicellular organisms, chemotaxis is critical in development as well as normal function. In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis.
Chemotaxis is called positive, if the movement is in the direction of the higher concentration of the chemical in question and negative, if the direction is opposite.
Eosinophil Chemotactic Factor of Anaphylaxis (ECF-A) is a substrate released from mast cells and basophils during anaphylaxis which attracts eosinophils . A tetrapeptide mediator of Immediate Hypersensitivity .