Activation of fibroblasts in collagen lattices by mast cell extract: a model of fibrosis

Abstract

Mast cells are resident connective tissue cells able to secrete numerous inflammatory mediators in response to tissue aggression and might be implicated in the fibrotic processes. To study the effects of mast cell products on fibroblast activity in connective tissues. Mast cell extract was prepared by sonication of pure mast cell preparations obtained by peritoneal lavage of rats and added to the culture medium of fibroblast-populated collagen lattices. Mast cell extract was able to decrease the contraction of the collagen lattices, to stimulate total protein and collagen synthesis, and to increase the expression and activation of gelatinase A/MMP-2. These data are consistent with the hypothesis that mast cells in connective tissue may be responsible for fibroblast activation at the early phases of tissue repair and fibrosis.