IL31 and allergic asthma: Indeed, Edukulla et al. [75], using a model of in vivo allergic asthma induced by soluble egg antigen, noticed that the absence of type II IL-4 receptor signaling is sufficient to attenuate the expression of IL-31RA, thus suggesting that Th2 cytokines are the main triggers of IL-31RA expression and play a crucial role in Th2-mediated IL-31/IL-31RA connections.