Epithelial-mesenchymal transition (EMT), a process whereby fully differentiated epithelial cells give rise to fibroblasts and myofibroblasts, is increasingly seen as playing a role in repair and scar formation following epithelial injury, reports the American Journal of Physiology—Lung Cellular and Molecular Physiology. Epithelial cells are membranous tissue that lines body cavities and vascular walls.

The study, conducted by Brigham C. Willis, MD, PhD, of the St. Joseph’s Hospital and Medical Center, Phoenix, and Zea Borok, MD, PhD, at the University of Southern California, Los Angeles, focuses on the contribution of EMT to fibrosis in adult tissues following injury, focusing especially on the critical role of transforming growth factor (TGF-beta).

Recently, it was demonstrated that (TGF)-beta induces EMT in alveolar epithelial cells (AEC) in vitro and in vivo, and epithelial and mesenchymal markers have been found in lung tissue from patients with idiopathic pulmonary fibrosis (IPF), suggesting that AEC may be a source of fibroblasts and myofibroblasts in the lungs.

Treatment for fibrosis of the lung in diseases such as IPF had previously focused reducing inflammation, but Willis and Borok will consider the cellular mechanisms of fibrogenesis in the lung and especially the role of the epithelium in this process, in hopes of a treatment.

To read the abstract, click here.