Transdifferentiation of alveolar epithelial type II to type I cells is controlled by opposing TGF-β and BMP signaling.

ABSTRACT: Alveolar epithelial type II (ATII) cells are essential for maintaining normal lung homeostasis because they produce surfactant, express innate immune proteins, and can function as progenitors for alveolar epithelial type I (ATI) cells. Although autocrine production of transforming growth factor (TGF)-β1 has been shown to promote the transdifferentiation of primary rat ATII to ATI cells in vitro, mechanisms controlling this process still remain poorly defined. Here, evidence is provided that Tgf-β1, -2, -3 mRNA and phosphorylated SMAD2 and SMAD3 significantly increase as primary cultures of mouse ATII cells transdifferentiate to ATI cells. Concomitantly, bone morphogenetic protein (Bmp)-2 and -4 mRNA, and phosphorylated SMAD1/5/8 expression decrease. Exogenously supplied recombinant human T

SUBMITTER: Zhao L 

PROVIDER: S-EPMC3763037 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature