C4A and asthma: Eosinophils are a characteristic feature of the pathology of asthma [19] in which the granular constituents of eosinophils are cytotoxic and cause desquamation and destruction of bronchial epithelium [20], which may lead to bronchial hyperresponsiveness [21]; lipid mediators secreted from eosinophils, such as leukotrienes C4, D4, and E4 and platelet activating factor, can induce bronchoconstriction, vascular permeability, and bronchial hyper responsiveness [20].