[Cytokine gene expression in interstitial lung diseases].
We studied the role of macrophages in the process of pulmonary fibrosis, focusing on gene expressions of cytokines. TGF-alpha is a factor which stimulates fibroblasts or endothelial cells to proliferate, by combining to receptors of EGF competitively with EGF in vitro. Total RNA was extracted from alveolar macrophages recovered by bronchoalveolar lavage from patients with idiopathic pulmonary fibrosis or normal healthy volunteers, and the expression of TGF-alpha mRNA was evaluated by Northern analysis. There was no detectable TGF-alpha mRNA in alveolar macrophages from normal healthy volunteers; however, in patients with idiopathic pulmonary fibrosis, a considerable level of mRNA of TGF-alpha could be detected. Using an experimental rat model of alveolitis induced by bleomycin, the expression of TNF-alpha mRNA in alveolar macrophages recovered by BAL was evaluated by Northern analysis. Alveolar macrophages from bleomycin-treated rats expressed a significant level of TNF-alpha mRNA. Both TGF-alpha and TNF-alpha have proliferative activity on fibroblasts, and may have an important role in the process of fibrosis of the lung.
Konishi
K
K
Third Department of Internal Medicine, Iwate Medical University.
Nakadate
T
T
Sugawara
K
K
Tamura
M
M
D002455:Cell Division; D066246:ErbB Receptors / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology; D015870:Gene Expression; D006801:Humans; D016676:Macrophages, Alveolar / Q000378:metabolism*; D011658:Pulmonary Fibrosis / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000032:analysis*; D016211:Transforming Growth Factor alpha / Q000235:genetics* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; D014409:Tumor Necrosis Factor-alpha; D066246:ErbB Receptors