Epithelium- and endothelium-derived exosomes regulate the alveolar macrophages by targeting RGS1 mediated calcium signaling-dependent immune response

Cell Death Differ. 2021 Jul;28(7):2238-2256. doi: 10.1038/s41418-021-00750-x. Epub 2021 Mar 22.

Abstract

Alveolar macrophages (AM) maintain airway immune balance; however, the regulation of heterogeneity of AMs is incompletely understood. We demonstrate that RGS1 coregulates the immunophenotype of AM subpopulations, including pro- and anti-inflammatory, injury- and repair-associated, and pro- and antifibrotic phenotypes, through the PLC-IP3R signal-dependent intracellular Ca2+ response. Flt3+ AMs and Tie2+ AMs had different immune properties, and RGS1 expression in the cells was targeted by exosomes (EXOs) containing miR-223 and miR-27b-3p that were derived from vascular endothelial cells (EnCs) and type II alveolar epithelial cells (EpCs-II), respectively. Imbalance of AMs was correlated with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) and pulmonary fibrosis (PF) caused a lack of secretion of CD31+ and CD74+ EXOs derived from EnCs and EpCs-II. Timely treatment with EXOs significantly improved endotoxin-induced ALI/ARDS and bleomycin-induced PF in mice. Thus, EnC- and EpC-II-derived EXOs regulate the immune balance of AMs and can be used as potential therapeutic drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Lung Injury / metabolism
  • Acute Lung Injury / therapy*
  • Alveolar Epithelial Cells / physiology
  • Animals
  • Calcium Signaling / immunology*
  • Endothelial Cells / physiology
  • Endothelium / metabolism
  • Epithelium / metabolism
  • Exosomes / metabolism
  • Exosomes / transplantation*
  • Humans
  • Immunity
  • Macrophages, Alveolar / metabolism*
  • Mice
  • RGS Proteins / genetics
  • RGS Proteins / metabolism*
  • Respiratory Distress Syndrome / metabolism
  • Respiratory Distress Syndrome / therapy*

Substances

  • RGS Proteins
  • RGS1 protein, human