Increase of lung neutrophils in hypersensitivity pneumonitis is associated with lung fibrosis. Academic Article uri icon

Overview

abstract

  • Hypersensitivity pneumonitis (HP) is characterized by a T-cell-mediated alveolitis, and the putative role of other inflammatory cells in its pathogenesis remains unclear. In this study we determined whether increased quantities of neutrophils were present in HP lungs, and if they were positive for gelatinase B and collagenase-2. Fifteen nonsmoking patients with subacute/chronic active HP were included. Lung samples were analyzed using myeloperoxidase antibody, and neutrophil/total cell ratio was evaluated by digital processing. All HP tissue samples exhibited variable quantities of neutrophils located inside vessels, and in the interstitial and alveolar spaces. Lung neutrophil percentage ranged from 0.7% to 4.8% (2.1 +/- 1.4%). There was a positive correlation between the percentage of lung neutrophils and the percentage of lung fibrosis (r = 0.6, p < 0.02). Tissue neutrophils showed intense immunoreactive collagenase-2 and gelatinase B staining. Additionally, gelatinolytic activities corresponding to progelatinases A and B and their activated forms, were several-fold increased in the bronchoalveolar lavage fluid (BALF) from patients with HP as compared with control subjects. These findings suggest that in HP lungs there is a persistent traffic of neutrophils loaded with gelatinase B and collagenase-2 that may play a role in the lung damage and in the fibrotic response.

publication date

  • May 1, 2000

Research

keywords

  • Alveolitis, Extrinsic Allergic
  • Lung
  • Neutrophils

Identity

Scopus Document Identifier

  • 0034027869

Digital Object Identifier (DOI)

  • 10.1164/ajrccm.161.5.9907065

PubMed ID

  • 10806177

Additional Document Info

volume

  • 161

issue

  • 5