RT Journal Article
SR Electronic
T1 Proteoglycans in granulomatous lung diseases
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 2731
OP 2737
DO 10.1183/09031936.97.10122731
VO 10
IS 12
A1 Bensadoun, ES
A1 Burke, AK
A1 Hogg, JC
A1 Roberts, CR
YR 1997
UL https://publications.ersnet.org//content/10/12/2731.abstract
AB In nongranulomatous fibrotic lung conditions, we have recently shown that early collagen synthesis by myofibroblasts occurs in an extracellular matrix rich in the proteoglycan versican. We hypothesized that versican is associated with the process of collagen synthesis resulting from chronic inflammation. In this study, we examined the localization of proteoglycans and collagen in the granulomatous lung conditions, sarcoidosis, extrinsic allergic alveolitis (EAA) and tuberculosis (TB). Tissue from individuals with sarcoidosis (n=6), EAA (n=4) and TB (n=2) was examined for glycosaminoglycans and collagen using histochemistry, and for versican, decorin, biglycan, hyaluronan, type I procollagen and alpha-smooth muscle actin using immunohistochemistry. The results showed that in sarcoidosis, EAA and TB, the rim of connective tissue surrounding granulomas contained glycosaminoglycans and collagen, and that glycosaminoglycan staining corresponded to localization of versican. Versican-rich zones contained myofibroblasts that stained intracellularly for type I procollagen. Hyaluronan was found diffusely throughout the matrix. Decorin was localized intracellularly in the epithelioid cells of granulomas and some myofibroblasts. We conclude that the deposition of versican is specific to the early remodelling process in both granulomatous and nongranulomatous lung diseases. In both forms of lung fibrosis, regardless of the nature of the driving inflammatory process, collagen synthesis takes place in a versican-rich provisional matrix. These results suggest that versican may influence the progression of the repair process following many different types of lung injury.