Circulating fibrocytes are an indicator of poor prognosis in idiopathic pulmonary fibrosis.

Abstract

RATIONALE:

The clinical management of idiopathic pulmonary fibrosis (IPF) remains a major challenge due to lack of effective drug therapy or accurate indicators for disease progression. Fibrocytes are circulating mesenchymal cell progenitors that are involved in tissue repair and fibrosis.

OBJECTIVES:

To test the hypothesis that assay of these cells may provide a biomarker for activity and progression of IPF.

METHODS:

Fibrocytes were defined as cells positive for CD45 and collagen-1 by flow cytometry and quantified in patients with stable IPF and during acute exacerbation of the disease. We investigated the clinical and prognostic value of fibrocyte counts by comparison with standard clinical parameters and survival. We used healthy age-matched volunteers and patients with acute respiratory distress syndrome as control subjects.

MEASUREMENTS AND MAIN RESULTS:

Fibrocytes were significantly elevated in patients with stable IPF (n = 51), with a further increase during acute disease exacerbation (n = 7; P < 0.001 vs. control subjects). Patients with acute respiratory distress syndrome (n = 10) were not different from healthy control subjects or stable patients with IPF. Fibrocyte numbers were not correlated with lung function or radiologic severity scores, but they were an independent predictor of early mortality. The mean survival of patients with fibrocytes higher than 5% of total blood leukocytes was 7.5 months compared with 27 months for patients with less than 5% (P < 0.0001).

CONCLUSIONS:

Fibrocytes are an indicator for disease activity of IPF and might be useful as a clinical marker for disease progression. This study suggests that quantification of circulating fibrocytes may allow prediction of early mortality in patients with IPF.

• Authors: Antje Moeller, Sarah E Gilpin, Kjetil Ask, Gerard Cox, Deborah Cook, Jack Gauldie, Peter J Margetts, Laszlo Farkas, Julian Dobranowski, Colm Boylan, Paul M O'Byrne, Robert M Strieter, Martin Kolb
• Journal: American journal of respiratory and critical care medicine (Am J Respir Crit Care Med) Vol. 179 Issue 7 Pg. 588-94 (Apr 01 2009) ISSN: 1535-4970 [Electronic] United States
• PMID: 19151190 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Leukocyte Common Antigens
• PTPRC protein, human

Topics

• Aged
• Biomarkers (blood)
• Case-Control Studies
• Cell Count
• Female
• Flow Cytometry
• Humans
• Idiopathic Pulmonary Fibrosis (blood, physiopathology)
• Leukocyte Common Antigens
• Male
• Mesenchymal Stem Cells (immunology, metabolism)
• Middle Aged
• Prognosis
• Proportional Hazards Models
• Prospective Studies
• Survival Analysis