Integrin alpha E beta 7 expression on BAL CD4+, CD8+, and gamma delta T-cells in bleomycin-induced lung fibrosis in mouse.

Abstract

CD4, CD8, and gamma delta T-cells located in the epithelium express the integrin alpha E beta 7 that binds to E-cadherin on the epithelium. Gamma delta T-cells mediate specific cellular immune functions and can recognize damaged cells directly. It was, therefore, of interest to analyse the presence of gamma delta T-cells and the expression of alpha E beta 7 on gamma delta T-cells in the bleomycin (BLM) model of pulmonary fibrosis. Lung fibrosis was induced by a single intratracheal instillation of BLM (0.125 U.mouse-1), and bronchoalveolar lavage (BAL) T-cell subpopulations were examined at various time-points for the expression of the integrin alpha E beta 7 by flow cytometry. CD4+ T-cells accounted for about 40% of the lymphocytes, compared to about 10% of CD8+ T-cells and 10-14% gamma delta T-cells. Within the CD4+ T-cell population the proportion of alpha E beta 7+ cells decreased between Days 2 and 22 from 36 to 11%. The percentage of alpha E beta 7+ CD8+ T-cells increased at the same time from 4 to 68%. However, more than 80% of the gamma delta T-cells in BAL fluid expressed alpha E beta 7 at all time-points. The surface-expression of this integrin on gamma delta T-cells was 2-3 times higher than on CD4+ or CD8+ T-cells. This predominant expression of alpha E beta 7 on gamma delta T-cells suggests a role for these cells in the pathogenesis of bleomycin-induced lung fibrosis.

• Authors: R K Braun, A Sterner-Kock, P J Kilshaw, D A Ferrick, S N Giri
• Journal: The European respiratory journal (Eur Respir J) Vol. 9 Issue 4 Pg. 673-9 (Apr 1996) ISSN: 0903-1936 [Print] England
• PMID: 8726930 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Cadherins
• Integrins
• Receptors, Antigen, T-Cell, gamma-delta
• Bleomycin
• Hydroxyproline

Topics

• Animals
• Bleomycin (adverse effects)
• Bronchoalveolar Lavage Fluid (cytology)
• CD4-Positive T-Lymphocytes (immunology)
• CD8-Positive T-Lymphocytes (immunology)
• Cadherins (physiology)
• Epithelium (chemistry)
• Flow Cytometry
• Hydroxyproline (analysis)
• Integrins (biosynthesis)
• Lymphocyte Count
• Male
• Mice
• Pulmonary Fibrosis (chemically induced, immunology)
• Receptors, Antigen, T-Cell, gamma-delta (immunology)
• T-Lymphocyte Subsets (immunology)