PPARG and pemphigus foliaceus: PGD2 stimulates macrophages to produce IL‐10, whereas PGD2 can be converted to PGJ2 and 15‐dPGJ2 to activate PPARγ, driving resolution.[7] By contrast, decreased levels of some eicosanoid metabolites of arachidonic acid are involved in the development of PF.[31] These findings were supported by the results of the present study, which showed that levels of 8,9‐EET and 14,15‐EET/14,15‐DHET were significantly higher, and the level of (S)8‐HETE was significantly lower, in the lungs of β‐glucan‐trained mice than in those of untrained mice during the early fibrotic phase following lung injury.