IL4 and influenza: Cytokines such as IL-4, IL-5, IL-6, IL-8, IL-13, and TNF-α, chemokines such as CCL2 and CCL3, and the MC proteases tryptase and chymase can be detected in the supernatants of influenza infected MC cultures and in the bronchioalveolar lavage fluid (BALF) of both influenza patients and infected mice (Table 2) (Yu et al., 2011; Hu et al., 2012; Graham et al., 2013; Betakova et al., 2017).