我们前期研究发现苦参碱衍生物MASM具有抗肝纤维化作用并特异结合层粘连蛋白受体(67LR)，67LR抗体和基因沉默可抑制肝星状细胞（HSC）活化并阻断MASM的作用，还发现纤维化肝脏中HSC高表达67LR，结果提示67LR 可能是介导MASM的作用靶点，并影响肝纤维化的进程。67LR参与肿瘤和感染等疾病过程使之成为药物干预的潜在靶点，但其与MASM抗肝纤维化作用及肝纤维化病理过程的关系未见报道。本项目将应用67LR抗体和小干扰RNA及其唯一的配体来确证67LR为MASM抗肝纤维化作用靶点；研究67LR在肝纤维化病理过程中的表达变化及其作用；采用基因敲除小鼠最终明确67LR在肝纤维化中的作用及对MASM作用的影响；初步探讨其细胞内信号通路以及通路是否影响MASM作用。研究结果将揭示67LR在肝纤维化中的作用，阐明MASM抗肝纤维化作用的细胞和分子机制，为肝纤维化治疗提供新的靶点和药物。

Our previous studies have found that matrine derive MASM exhibits potent antifibrotic and antiinflamatory effects and specifically binds to the 67-kD laminin receptor (67LR). The 67LR antibody prevented hepatic stellate cell (HSC) activation and noticeably blocked inhibitory effect of MASM on HSC activation, indicating that MASM may act on extracellular 67LR. This observation was further supported by the 67LR knockdown that efficiently reduced extracelluar 67LR expression. In addition, immunohistochemical analysis of the experimental fibrotic liver revealed that the 67LR expression was strikingly increased and localized exclusively to the α-SMA positive cells. These results suggest that antifibrotic effect of MASM may be mediated by the 67LR and this receptor may represent a novel target for future therapeutic approach in liver fibrosis. The 67LR has been associated with cancer metastasis, bacterial and viral infection and other pathological events that make it a prime target for therapeutic interventions. There are not any reports about matrine and its derivatives as a 67LR ligand and involvement of the 67LR in hepatic fibrosis at present. This project will validate 67LR as cell membrane receptor of MASM using 67LR antibody, siRNA and known ligand EGCG. In addition, we will investigate the dynamic change of 67LR expression during the process of liver fibrosis. Moreover, the role of RPS5 in the pathological process of liver fibrosis will be studied in vitro and in vivo using lentivirus carrying HSC specific glial fibrillary acidic protein （GFAP）GFAP promoter-driver 67LR overexpression or knockdown as well as 67LR knockout mouse. Meanwhile, we will study whether benifical effect of MASM on hepatic fibrosis is lost in such systems. Lastly, we will identify 67LR cytosol binding proteins to investigate the signal transduction process, and investigate how these signal molecules affect MASM’s action. Together，our results will clarify the molecular mechanism of MASM for its antifibrotic effects and point to 67LR as a therapeutic target for liver fibrosis.