State-of-the-art review about basophil research in immunology and allergy: is the time right to treat these cells with the respect they deserve?

previously unrecognised roles for basophils in both allergic responses and immune regulation, and have markedly altered our image of these cells, from a neglected minority to key players in the immune system. Research on basophils was hampered for a long time because of the paucity of these cells in peripheral blood, which often resulted in scant yields and diffi culty in their isolation, forcing researchers to use time-consuming and quite expensive approaches for their physical purification. Furthermore, the lack of genetically homogeneous cell lines and of a true genetic knock-out animal model (only mice depleted of basophils by anti-receptor antibodies and a few transgenic animals are available), the existence of a relatively high response variability among the healthy population and the diffi culty of purifying the cells from blood have made it very diffi cult to study this subgroup of leucocytes. With the respectable exception of allergists, it seems that most immunologists and immuno-haematologists have given up. All this has shifted attention to mast cells, which are easier to handle. Nevertheless, in clinical settings, basophils are a practical and convenient alternative for the diagnosis of allergy because they are much more accessible than tissue-resident mast cells and it is suffi cient to take a blood sample in order to obtain them. Basophils are circulating blood granulocytes that are mainly involved in hypersensitivity (atopic) and anaphylactic reactions 2-5 ; they stem from CD34 +