BASIC INVESTIGATIONS ON RETROVIRAL-MEDIATED GENE THERAPY TOWARD HEPATOMA BY USE OF ALBUMIN ENHANCER AND PROMOTER AS A TISSUE-SPECIFIC REGULATORY ELEMENT

Recent remarkable developments in molecular biology and in vitro culture techniques have provided a promising new treatment, gene therapy, for cancer and congenital genetic diseases. For in vivo gene therapy toward cancer, it is indispensable to direct the expression of exogenous genes exclusively to cancer cells. I have constructed a recombinant retroviral vector in which a tissue-specific regulatory element is used as an internal promoter. It contains the murine albumin enhancer and promoter as an internal promoter and the lacZ gene coding bacterial β-galactosidase as a reporter between the two Moloney murine leukemia virus long terminal repeats. This vector was introduced into ecotropic retroviral ψ2　packaging cells to produce recombinant retroviral particles. Various cell lines were infected with the recombinant retrovirus to assess its tissue specificity in vitro. Expression of the lacZ gene was detected solely in hepatoma cell lines but not in fibroblasts nor in B lymphoma cells. In vivo infection was carried out to evaluate tissue specificity of this system. The recombinant retrovirus was injected into a murine subcutaneous hepatoma and expression of the lacZ gene was observed in hepatoma cells but not in surrounding connective tissues. Then the retrovirus was injected into murine livers and no expression was detected in normal hepatocytes. The retrovirus was again injected into the livers of partially hepatectomized mice, resulting in the gene expression in only a few regenerating hepatocytes. Ratio of expression of the exogenous gene was, however, much lower than that in subcutaneous hepatoma. Finally, the gene expression of higher efficiency was confirmed as the retroviral infections were repeated. These results indicate that repeated gene transfer by means of the recombinant retrovirus which contains a tissue-specific regulatory element as an internal promoter should possess high potential for selective elimination of hepatoma cells in vivo

慢性C型肝炎にみられる肝炎性胆管障害の免疫病理学的検討 : 原発性胆汁性肝硬変との比較を中心に

金沢大学医学

いわゆる"細胆管増生"に関する病理学的研究 細胞形質,細胞動態およびトランスフォーミング増殖因子アルファ発現の解析を中心に

金沢大学 医 第2病理1)定型的細胆管は,全ての肝胆道型疾患で種々の程度に増生していた.非定型的細胆管は,PBCやPSC等の原発性胆道系疾患及び肝外閉塞性黄疸,アルコール性肝線維症,亜広汎性肝壊死,肝硬変,慢性活動性肝炎例で種々の程度と頻度でみられた. 2)定型的細胆管は胆管上皮固有の表現型を有し,増殖活性の亢進も認めた.小葉間胆管での胆管上皮細胞の増殖活性も亢進していた.つまり,定型的細胆管増生は既存の胆管上皮細胞からの増生による. 3)細胞増殖活性の弱い非定型的細胆管はPBCやPSC等の慢性胆汁うっ滞例でみられ,主として肝細胞の化生による見かけ上の増生である. 4)増殖活性の高い非定型的細胆管は肝外閉塞性黄疸,亜広汎性肝壊死,肝硬変や慢性活動性肝炎例でみられ,不完全な表現型の発現を示す胆管細胞の増殖と考えられ,これら疾患での肝細胞消失に関連する一つの現象と考えられ