Few studies in humans and animals have demonstrated down regulation of one endogenous effector of resolution, the protein AnxA1, during the development of cystic fibrosis [24,25]; the present study was intended to address, for the first time, the potential relevance of AnxA1 in experimental fibrosis using the recently generated AnxA1 null mouse [14,15]. Here, ANXA1 is linked to cystic fibrosis.