[Pulmonary manifestation of collagen vascular diseases: role of cytokines in interstitial pneumonia associated with collagen vascular diseases].

Although the pathological patterns of interstitial pneumonia associated with collagen vascular disease (CVD-IP) resemble those of usual interstitial pneumonia in idiopathic interstitial pneumonia (IIP), the clinical features of CVD-IP and IIIP are quite different. We evaluated the differences between these conditions, with regard to the expression of genes in cells obtained by bronchoalveolar lavage. The reverse transcription-polymerase chain reaction was used to measure the levels of mRNA for IL-1 beta, TNF-alpha, IL-8, TGF-beta, PDGF-B, and IGF-1, and no significant differences were found between patients with CVD-IP and those with IIP. However, differential display analysis revealed a fragment that can be considered to have been derived from an unknown gene mRNA, and this was found only in patients with pulmonary fibrosis associated with progressive systemic sclerosis. Expression of specific genes may differentiate CVD-IP from IIP.