Schematic representation of the biology of IL-5 [36], eosinophils and their mediators [29,73], and their effect on asthma. The point in this cascade where therapies targeting IL-5 or its receptor act is shown. Depletion of cells expressing IL-5Ra (eosinophils and basophils) results from antibody-directed cell-dependent cytotoxicity.
The HE-stained eosinophil was adapted with permission from wordpress.com [74].
Eos: Eosinophils; EPO: Eosinophil peroxidase; ILC2: Group 2 innate lymphoid cells; LTC4: Cysteinyl leukotriene C4; MBP: Major basic protein; MC: Mast cells; MMP-9: Matrix metalloproteinase 9; PAF: Platelet-activating factor.