Hamzaoui A, Ghraïri H, Ammar J, Zekri S, Guemira F, Hamzaoui K
Department of Respiratory Diseases, Pneumology Hospital A. Mami, Ariana, Tunisia.
Clin Exp Rheumatol. 2003 Jul-Aug;21(4 Suppl 30):S8-14.
IL-18 expression and functional activity has been identified in several autoimmune and infectious diseases. To clarify the potential role of IL-18 during pulmonary Behçet's disease (BD), we have explored the capacity of IL-18 to induce the expression of IFN-gamma.
We studied bronchoalveolar lavage (BAL) from 12 patients with BD, 10 patients with silicosis as the control disease and 10 BAL from healthy subjects. BAL fluid, and BAL fluid cell cultures were investigated for IL-18 estimation by ELISA. Analysis of IL-18 and IFN-gamma gene expression was carried out before and after LPS stimulation.
BD patients had significantly elevated levels of IL-18 in BAL fluid compared with control disease and healthy subjects. Induction of IFN-gamma and IL-18 were observed from BD-BAL fluid cells both spontaneously and after LPS stimulation, at higher levels compared to silicosis patients and healthy subjects (HC). Spontaneously only BD BAL cells expressed IL-18 mRNA and IFN-gamma mRNA. Forty-eight hours after LPS stimulation IL-18 mRNA and IFN-gamma mRNA were observed in BD, silicosis and HC cells. Recombinant IL-18 induced IFN-gamma production in BD- BAL fluid cells.
Administration of IL-18 induced greater IFN-gamma production in BD-BAL fluid cells, than in normal BAL fluid cells. Our data indicate that IL-18 up-regulation is a feature of BD and suggest that IL-18 and IFN-gamma may contribute to the local inflammatory response in BD.
白细胞介素-18（IL-18）的表达及功能活性已在多种自身免疫性疾病和感染性疾病中得到确认。为阐明IL-18在肺部白塞病（BD）中的潜在作用，我们探究了IL-18诱导γ干扰素（IFN-γ）表达的能力。
我们研究了12例BD患者、10例矽肺患者（作为对照疾病）以及10例健康受试者的支气管肺泡灌洗（BAL）样本。通过酶联免疫吸附测定（ELISA）检测BAL液及BAL液细胞培养物中的IL-18含量。在脂多糖（LPS）刺激前后，对IL-18和IFN-γ基因表达进行分析。
与对照疾病患者和健康受试者相比，BD患者BAL液中的IL-18水平显著升高。BD患者BAL液细胞在自发状态下以及LPS刺激后均能观察到IFN-γ和IL-18的诱导表达，且水平高于矽肺患者和健康受试者（HC）。仅BD患者的BAL细胞在自发状态下表达IL-18信使核糖核酸（mRNA）和IFN-γ mRNA。LPS刺激48小时后，在BD患者、矽肺患者和HC细胞中均观察到IL-18 mRNA和IFN-γ mRNA。重组IL-18可诱导BD患者BAL液细胞产生IFN-γ。
给予IL-18后，BD患者BAL液细胞产生的IFN-γ比正常BAL液细胞更多。我们的数据表明，IL-18上调是BD的一个特征，并提示IL-18和IFN-γ可能参与了BD的局部炎症反应。
