Pulmonary toxicants and fibrosis: innate and adaptive immune mechanisms

Toxicol Appl Pharmacol. 2020 Dec 15:409:115272. doi: 10.1016/j.taap.2020.115272. Epub 2020 Oct 5.


Pulmonary fibrosis is characterized by destruction and remodeling of the lung due to an accumulation of collagen and other extracellular matrix components in the tissue. This results in progressive irreversible decreases in lung capacity, impaired gas exchange and eventually, hypoxemia. A number of inhaled and systemic toxicants including bleomycin, silica, asbestos, nanoparticles, mustard vesicants, nitrofurantoin, amiodarone, and ionizing radiation have been identified. In this article, we review the role of innate and adaptive immune cells and mediators they release in the pathogenesis of fibrotic pathologies induced by pulmonary toxicants. A better understanding of the pathogenic mechanisms underlying fibrogenesis may lead to the development of new therapeutic approaches for patients with these debilitating and largely irreversible chronic diseases.

Keywords: fibroblasts; fibrosis; immune cells; inflammation; macrophages; mustard vesicants; toxicants.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Adaptive Immunity / immunology*
  • Animals
  • Chronic Disease
  • Hazardous Substances / immunology*
  • Hazardous Substances / toxicity
  • Humans
  • Immunity, Innate / immunology*
  • Lung / drug effects*
  • Lung / immunology*
  • Pulmonary Fibrosis / chemically induced*
  • Pulmonary Fibrosis / immunology*


  • Hazardous Substances