Type III and Type I Procollagen Markers in Fibrosing Alveolitis

Abstract

Deposition of types I and III collagen is a typical feature in the development of pulmonary fibrosis. We assessed the propeptides of these procollagens as prognostic markers in 18 patients with fibrosing alveolitis. We analyzed the amino-terminal propeptide of type III procollagen (PIIINP) and the carboxy-terminal propeptide of type I procollagen (PICP) from samples of bronchoalveolar lavage fluid (BALF) and serum, and also estimated their concentrations in epithelial lining fluid (ELF) by the urea method. The level of PIIINP in serum (p < 0.05), BALF (p < 0.05), and ELF (p < 0.05), and the levels of PICP in BALF (p < 0.001) and ELF (p < 0.001) but not in serum, were significantly increased in the patients with fibrosing alveolitis as compared with 17 controls who had been investigated for minor respiratory symptoms. In the BALF and ELF of patients with fibrosing alveolitis, PICP but not PIIINP had significant negative correlations with the specific diffusion coefficient for carbon monoxide (DLCO/ VA). The amino-terminal propeptide of type III procollagen and the carboxy-terminal propeptide of type I procollagen in BALF correlated significantly with one another. During the follow-up period of 6 yr, seven of the 18 patients with fibrosing alveolitis died of the disease, 3 others died of malignancy, and one patient died from an unknown cause. DLCO (p < 0.05) differed significantly between the surviving patients and those who died of fibrosing alveolitis, and detectable PIIINP in BALF predicted death from fibrosing alveolitis (p = 0.05). In conclusion, these results show that PIIINP in BALF, ELF, and serum, and PICP in BALF and ELF, are increased in patients with fibrosing alveolitis. A high level of PICP in BALF, and especially in ELF, suggests a chronic process and increased synthesis of type I collagen in the lungs, whereas PIIINP in BALF and ELF suggests active disease and a poor prognosis.

RGTA OTR4120, a heparan sulfate mimetic, is a possible long‐term active agent to heal burned skin

“…17 Presence of a relative increase in collagen III is often associated with fibrosis and excessive scarring in many diseases. 12,[35][36][37] Antifibrotic effects of RGTA have been demonstrated in earlier studies. Thus, RGTA treatment decreased the production of collagen III in intestinal tissue specimens from patients with Crohn's disease.…”

Concentration of hydroxyproline in blood: A biological marker in occupational exposure to asbestos and its relationship with Pi*Z and Pi*S polymorphism in the alpha‐1 antitrypsin gene

“…The former is theoretically a better marker of collagen synthesis than PIIINP and BALF PICP seems to better reflects the fibrosis in these diseases [Lammi et al, 1997[Lammi et al, , 1999b. Moreover, epithelial lining fluid -PICP is elevated in asbestosis [Lammi et al, 1999a] with parenchymal involvement.…”

Metalloproteinases in idiopathic pulmonary fibrosis

“…PICP levels in the BALF and epithelial lining fluid had a significant negative correlation with diffusing capacity of the lung for carbon monoxide per unit of alveolar volume [13]. In immunohistochemical or in situ mRNA studies on lung tissue, type III collagen is predominant in the thickened alveolar septa and interstitium, whereas type I collagen appears to be the principal collagen at later stages in the disease course [14].…”