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

热休克蛋白（HSP） 47作为一种胶原特异性分子伴侣参与多种胶原的合成/组装。hsp47在肝硬化和其他纤维化疾病中表达上调。我们研究了中性粒细胞azurophil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HSP47和胶原蛋白的影响，以及在博莱霉素诱导的小鼠肺纤维化中HSP47表达与纤维化过程的关系。首先，我们利用人类患者的手术活检标本，证实了特发性通常间质性肺炎（UIP）患者肺成纤维细胞和II型肺细胞中HSP47的表达明显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，其预后更好。我们还研究了α- defend . More sin (human neutropil peptide， HNP)-1)对人肺成纤维细胞HSP47和胶原-1表达的影响。5 μg/ml的HNP-1可诱导成纤维细胞增殖，50 μg/ml的HNP-1可降低成纤维细胞活力。10 ~ 25 μg/ml的HNP-1可显著提高hsp47和collagen-1 mRNA的表达，并使其蛋白释放量呈剂量依赖性增加。tgf - β也增强了这些mRNA和蛋白在人正常成纤维细胞和A549细胞中的表达，而吡非尼酮抑制了这些发现。此外，我们正在使用real - time PCR技术研究tgf - β对A549和成纤维细胞中PDGF和HGF等生长因子表达的影响。在博莱霉素诱导的小鼠肺纤维化中，原位杂交也观察到肺纤维化程度与HSP47的表达有良好的相关性。我们的研究结果提示α-防御素可能通过上调人肺成纤维细胞中HSP47和胶原-1直接促进纤维化过程，在肺纤维化的发病机制中发挥重要作用，HSP47阳性细胞可能具有增强胶原合成和释放的能力。吡非尼酮直接抑制肺纤维化中细胞外基质积累和沉积的阳性细胞。这些发现提示BSP47和α-防御素可能是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