Kinetics of M2 polarization in mice after the induction of an acute allergic airway inflammation. Alveolar (AMΦ, open circles) and interstitial (IMΦ, closed circles) macrophages were isolated 1 day (24 h), 1 week (wk), 2 wk and 3 wk after ovalbumin aerosol provocation. A, Eosinophil numbers, IL-4 and IL-13 levels (n = 7). Data were analyzed with one way ANOVA. *** P < .001. B, Gene expression of M2 markers Arginase, Fizz1, and YM1 are presented as fold induction compared to PBS treated mice (each data point represents n = 5 pooled animals).