IL13 and asthma: It is well-recognized that altered [Ca2+]i regulation is a key component of the pathophysiology of airway diseases such as asthma [34] and chronic obstructive pulmonary disease [35] where increased expression of inflammatory cytokines such as tumor necrosis factor-alpha (TNFα) and the interleukins (IL) IL-1β and IL-13 enhance ASM contractility [36].