Eosinophils in Asthma: Remodeling a Tangled Tale

The prevalence of allergic asthma in the developed world has spurred efforts to understand the pathogenesis of this debilitating disease, but there is much confusion and controversy. One of the biggest debates is the involvement of eosinophils, which are found at sites of airway inflammation. In their Perspective, Wills-Karp and Karp discuss the work of two groups, that have independently generated mice that lack eosinophils ( Humbles et al.; Lee et al.). Although many of their findings seem to conflict, the two studies do agree that eosinophils contribute to clinical asthma.