ABSTRACT
Fibronectin (Fn) and tenascin (Tn) are two major extracellular matrix glycoproteins participating in tissue morphogenesis and repair. The regulation of their synthesis and deposition during airway inflammation and their possible contribution in asthma are poorly understood. In this study, modulation of Fn and Tn production was investigated in transformed human bronchial epithelial cells in culture. The cells were treated with interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), a combination of these cytokines, interleukins 3 and 6 (IL-3 and IL-6), granulocyte macrophage-colony stimulating factor (GM-CSF), and a combination of IL-3 and IL-6 for 48 h. Immunofluorescence and immunoblotting methods with monoclonal antibodies to Fn and Tn antibodies suggested the production of some Fn and Tn in the untreated cells. Fn was minimally induced in response to IFN-gamma and TNF-alpha, when compared with the untreated cells, whereas TNF-alpha and especially the IFN-gamma plus TNF-alpha combination resulted in a prominent Tn induction. Interleukins and GM-CSF did not induce Fn or Tn in any case. These results show that human bronchial epithelial cells are capable of producing Fn and Tn. The modulation of Fn and Tn may have an important impact on the pathology of epithelial cells during airway inflammation in vivo.
