Format

Send to

Choose Destination
Am J Respir Cell Mol Biol. 1997 Sep;17(3):344-52.

Expression of lung vascular and airway ICAM-1 after exposure to bacterial lipopolysaccharide.

Author information

1
Institute for Anaesthesiology and Department of Surgery, University of Zurich Medical School, Switzerland.

Abstract

Airway instillation of bacterial lipopolysaccharide (LPS) into rat lungs induces neutrophil accumulation, which is known to be intercellular adhesion molecule-1 (ICAM-1)-dependent. In the present study, ICAM-1 messenger RNA (mRNA) of whole lung was found to increase by 20-fold in this inflammatory model. This increase was reduced by 81% after treatment of animals with anti-tumor necrosis factor-alpha (TNF-alpha) antibody and by 37% after treatment with anti-interleukin-1 (IL-1) antibody. The same interventions reduced whole-lung ICAM-1 protein by 85% and 25%, respectively. The studies were extended to assess the locale in lung of ICAM-I upregulation. Lung vascular ICAM-1 content, which was assessed by vascular fixation of [125I]anti-ICAM-1, rose 4-fold after airway instillation of LPS. This rise was also TNF-alpha-dependent. Under the same experimental conditions, fixation of [125I]anti-ICAM-1 to airway surfaces increased 11-fold in a TNF-alpha-dependent manner. In situ hybridization and immunohistochemical analyses of lung tissue revealed ICAM-1 upregulation in the bronchiolar epithelium and in peribronchiolar smooth muscle. Soluble ICAM-1 could also be detected in bronchoalveolar lavage fluids (BALFs) of animals after intratracheal instillation of LPS. Retrieved alveolar macrophages showed a small, significant, and transient increase in surface expression of ICAM-1. These data indicate, at the very least, a dual compartmentalized (vascular and airway) upregulation of ICAM-1 after airway instillation of LPS. This upregulation requires TNF-alpha and IL-1. The functional significance of upregulated airway ICAM-1 remains to be determined.

PMID:
9308921
DOI:
10.1165/ajrcmb.17.3.2861
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center