Elevated matrilysin levels in bronchoalveolar lavage fluid do not distinguish idiopathic pulmonary fibrosis from other interstitial lung diseases

• Published in: APMIS : acta pathologica, microbiologica et immunologica Scandinavica Vol. 115; no. 8; pp. 969 - 975
• Main Authors: VUORINEN, KIRSI, MYLLÄRNIEMI, MARJUKKA, LAMMI, LAURI, PIIRILÄ, PÄIVI, RYTILÄ, PAULA, SALMENKIVI, KAISA, KINNULA, VUOKKO L.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2007; Blackwell
• Subjects: Adult; Aged; Biological and medical sciences; Bronchoalveolar Lavage Fluid - chemistry; Diagnosis, Differential; Female; Humans; Idiopathic pulmonary fibrosis; Immunohistochemistry; Lung - enzymology; Lung Diseases, Interstitial - diagnosis; Lung Diseases, Interstitial - enzymology; Male; Matrix Metalloproteinase 7 - analysis; matrix metalloproteinase-7; Medical sciences; Middle Aged; nonspecific interstitial pneumonia; Pneumology; Pulmonary Fibrosis - diagnosis; Pulmonary Fibrosis - enzymology; pulmonary sarcoidosis; Respiratory system : syndromes and miscellaneous diseases; Human; Lung disease; Biological fluid; Enzyme; Respiratory disease; Idiopathic pulmonary fibrosis; Idiopathic; matrix metalloproteinase-7; Biological marker; Metalloendopeptidases; nonspecific interstitial pneumonia; Differential diagnostic; pulmonary sarcoidosis; Peptidases; Pulmonary fibrosis; Bronchoalveolar lavage; Interstitial pneumonitis; Hydrolases; Matrilysin
• ISSN: 0903-4641; 1600-0463
• DOI: 10.1111/j.1600-0463.2007.apm_697.x

Microarray studies have shown that matrilysin or matrix metalloproteinase (MMP)‐7 is highly upregulated in the lungs of patients with idiopathic pulmonary fibrosis (IPF), but MMP‐7 protein expression has not been systematically compared between IPF and other interstitial lung diseases. MMP‐7 levels in bronchoalveolar lavage fluid (BALF) were compared to corresponding samples from nonspecific interstitial pneumonia (NSIP), sarcoidosis, and healthy controls. MMP‐7 levels in the BALF were determined by ELISA and localization of MMP‐7 in the lung tissue by immunohistochemistry. MMP‐7 was similarly elevated in the BALF of all these disorders compared to healthy controls (p=0.007). Even control subjects with prolonged cough displayed a tendency towards elevated MMP‐7 expression. There was a negative correlation between BALF MMP‐7 levels and forced expiratory vital capacity (r=−0.348, p=0.02, n=42). In IPF lung, MMP‐7 immunoreactivity appeared predominantly in the fibrotic parenchyma and arterial wall. In sarcoidosis and NSIP, prominent MMP‐7 immunoreactivity was found in areas of inflammation. These results demonstrate that elevated BALF MMP‐7 is not restricted to IPF alone but is also observed in other interstitial lung diseases and cannot be used as a differential diagnostic marker for IPF.