Role of IL-5-activated eosinophils on collagen gel contraction by lung fibroblasts / 천식및알레르기

BACKGROUND: Subepithelial fibrosis plays a major role in the development of irreversible airway obstruction in asthma. Eosinophils are major effector cells in allergic inflammation, and it has been suggested that eosinophil-derived mediators such as transforming growth factor-beta (TGF-beta) play a role in the pathogenesis of airway remodeling. OBJECTIVE: The aim of this study was to evaluate whether eosinophils activated by IL-5 plays a major role in the collagen gel contraction by lung fibroblasts. METHOD: Various cell numbers of lung fibroblasts were cultured in collagen gels to determine the appropriate numbers of fibroblasts. Purified human peripheral blood eosinophils were activated by IL-5 for 3 days, and TGF-beta mRNA expression was evaluated using semiquantitative RT- PCR. The cultured supernatants with or without TGF-beta were added to the collagen gel media with lung fibroblasts, and collagen gel diameter was serially measured to evaluate collagen gel contraction. RESULTS: The amount of collagen gel contraction was significantly associated with the number of fibroblasts (p 0.05). Moreover, expression of TGF-beta mRNA in eosinophils was the same before and after stimulus of IL-5. CONCLUSION: Activated eosinophils by IL-5 may play a minor role in the collagen gel contraction by lung fibroblasts.

Collagen Gel Contraction by Cultured Fibroblasts Derived from Normal Skin, Oral Mucosa, and Hypertrophic Scar / 대한피부과학회지

BACKGROUND: The degree of scar formation varies according to the sites. Oral mucosa heals faster with lesser scar formation than skin and it is very rare for oral mucosa to develop hypertrophic scars. Collagen gel seeded with fibroblasts is considered as a valuable model for studying wound healing in vitro. OBJECTIVE: The purpose of this study was to find out whether there are any differences in contractiliy of collagen gel by fibroblasts derived from different sites. METHODS: Fibroblasts were cultured from normal skin, oral mucosa, and hypertrophic scar. They were seeded into collagen gel with or without serum, and the degree of contraction of the collagen gel was measured for 5 days. RESULTS: Hypertrophic scar fibroblasts in collagen gel possessed the greatest contraction potency followed by normal skin fibroblasts and oral mucosal fibroblasts. Serum significantly increased the contractility of each of the fibroblasts. The differences of contractility of collagen gel between oral mucosal fibroblasts and others became more obvious in the presence of serum, however, those between normal skin fibroblasts and hypertrophic scar fibroblasts became less obvious. CONCLUSION: The degree of contraction of collagen gel by fibroblasts correlated with the degree of scar formation. Addition of serum modified the degree of contractile potency which may reflect the differences in the fibroblasts with phenotypic alteration and the subtype of fibroblasts.