Research of heat shock protein 47 and defensins in the pathogenesis of pulmonary fibrosis

热休克蛋白（HSP）47作为胶原特异性分子伴侣参与多种胶原的合成/组装。HSP 47在肝硬化和其他纤维化疾病中表达上调。本实验研究了中性粒细胞嗜天青颗粒中具有抗菌和细胞毒活性的阳离子蛋白α-防御素（α-defensin）对肺成纤维细胞产生HSP 47和胶原的影响，以及HSP 47表达与肺纤维化过程的关系。首先，我们使用来自人类患者的手术活检标本，证明了特发性普通型间质性肺炎（UIP）患者肺成纤维细胞和II型肺细胞中HSP 47的表达显著高于胶原血管病相关的UIP和特发性非特异性间质性肺炎，与特发性UIP相比，其具有更好的预后。我们还研究了α-defen的直接作用 ...更多信息 人中性粒细胞肽（HNP）-1对人肺成纤维细胞HSP 47和胶原-1表达影响HNP-1 5 μg/ml诱导成纤维细胞增殖，>50 μg/ml的HNP-1降低细胞活力。10 ~ 25 μg/ml的HNP-1可显著增加HSP 47和胶原-1mRNA的表达，而其蛋白释放量呈剂量依赖性增加。TGF-β还增强了人正常成纤维细胞和A549细胞中这些mRNA和蛋白质的表达，吡非尼酮抑制了这些发现。此外，我们还利用真实的时间PCR研究了TGF-β对A549和成纤维细胞中生长因子包括PDGF和HGF表达的影响。在小鼠博莱霉素诱导的肺纤维化，肺纤维化的程度和HSP 47的表达之间也观察到了良好的相关性，使用原位杂交。结果提示，α-防御素可能通过上调人肺成纤维细胞HSP 47和胶原-1直接促进肺纤维化的发生，在肺纤维化的发病机制中起重要作用，HSP 47阳性细胞可能具有促进胶原合成和释放的能力。吡非尼酮直接抑制这些阳性细胞，这些阳性细胞负责肺纤维化中观察到的细胞外基质的积累和沉积。提示BSP 47和α-防御素可能成为治疗特发性肺纤维化的新靶点。少

Heat shock Protein (HSP) 47 is involved in the synthesis/assembly of various collagens as a collagen-Specific molecular chaperone. HSP 47 expression has been shown upregulated in liver cirrhosis and other fibrotic diseases. We have studied the effect of α-defensin, cationic proteins with antimicrobial and cytotoxic activity in the azurophil granule of neutrophils, on the production of HSP 47 and collagen using lung fibroblasts, and the relationship between HSP47 expression and fibrotic process in murine bleomycin-induced pulmonary fibrosis. At first, using surgical biopsy specimens from human patients, we demonstrated that expression of HSP47 in lung fibroblasts and type II pneumocytes was significantly higher in idiopathic usual interstitial pneumonia (UIP) patients than in those with collagen vascular disease-associated UIP and idiopathic non-specific interstitial pneumonia, which has the better prognosis compared with idiopathic UIP. We also investigated the direct effect of α-defen … More sin (human neutrophil peptide (HNP)-1) on expression of HSP47 and collagen-1 in human lung fibroblasts. HNP-1 5 μg/ml induced fibroblast proliferatioh and concentrations >50 μg/ml of HNP-1 reduced the cell-viability. Expression of HSP 47 and collagen-1 mRNA was significantly increased by 10 to 25 μg/ml of HNP-1, whereas their protein release increased in dose-dependent manner. TGF-beta also enhanced the expression of these mRNA and proteins in human normal fibroblasts and A549 cells, and pirfenidone inhibited these findings. In addition, We are studying the effects of TGF-beta on expression of growth factors including PDGF and HGF in A549 and fibroblasts using real time PCR. In murine bleomycin-induced pulmonary fibrosis, a good correlation was also observed between the degree of pulmonary fibrosis and expression of HSP47 using in situ hybridization. Our results suggest that α-defensin may promote directly fibrotic process through upregulation of HSP 47 and collagen-1 in human lung fibroblasts and play an important role in the pathogenesis of pulmonary fibrosis and HSP47 positive cells may have an ability of enhanced collagen synthesis and release. Pirfenidone inhibited directly these positive cells responsible for the accumulation and deposition of extracellular matrix seen in pulmonary fibrosis. These findings suggest that BSP47 and α-defensin might be anew promising target for the treatment of idiopathic pulmonary fibrosis. Less