THE HISTOGENESIS OF MALIGNANT FIBROUS HISTIOCYTOMA (MFH), WITH THE SPECIAL REFERENCE TO MULTIPOTENTIAL DIFFERENTIATION OF MFH CELLS

恶性纤维组织细胞瘤（MFH）的组织发生至今尚未确定。我们已经研究了组织发生使用克隆细胞系（MT-8，未分化的间充质细胞; MT-9，间充质细胞与组织细胞和成纤维细胞的性质）来自可移植的大鼠MFH。(1)通过向培养基中加入对巨噬细胞功能有潜在刺激作用的贫血血清或脂多糖，MT-8和MT-9细胞增强了它们的组织细胞性质。(2)分别从MT-8和MT-9细胞诱导顺铂（抗癌药物）抗性细胞系（MT-R8和MT-R9）。MT-R8和MT-R9细胞增强了组织细胞和肌纤维母细胞的性质，并且进一步地，MT-R9细胞在同基因大鼠中诱导的肿瘤显示出多种组织学：肌纤维母细胞和颗粒细胞的肿瘤性增殖、骨肉瘤样区域和涉及许多成脂肪细胞的区域。(3)我们研究了MFH中“组织细胞”的起源和抗RA的免疫表型， ...更多信息 t组织细胞特异性抗体（ED 1和ED 2）。结果表明，组织细胞的起源和免疫表型存在异质性。(4)制备了抗MT-8细胞的单克隆抗体，并对染色模式进行了化学染色研究。已经阐明，MFH细胞和未分化的间充质细胞或巨噬细胞系细胞之间存在共同抗原，表明MFH构成细胞的细胞性质的异质性。(5)我们建立了大鼠组织细胞肉瘤、纤维肉瘤和恶性脑膜瘤的可移植性肿瘤和细胞系，并对MFH细胞和这些间充质细胞系的细胞性质进行了比较。结果表明，MFH与其它间叶肿瘤细胞的生物学特性有明显差异。(6)根据这些结果，可以得出结论，MFH由间充质细胞在不同的分化阶段，从未分化的细胞与组织细胞和成纤维细胞性质的细胞转移;细胞性质可以很容易地改变，大概取决于微环境/遗传因素。MFH细胞可能是具有多向分化潜能的间充质祖细胞。细胞的性质似乎有助于无休止的，不稳定的组织学MFH。(7)本研究所建立的大鼠MFH细胞系为研究MFH的组织发生和间充质分化提供了一个有用的实验系统。少

The histogenesis of malignant fibrous histiocytoma (MFH) is still undetermined. We have investigated the histogenesis using cloned cell lines (MT-8, undifferentiated mesenchymal cells ; MT-9, mesenchymal cells with both natures of histiocytes and fibroblasts) derived from transplantable rat MFH.(1) By adding hyperlipemic serum or lipopolysaccharide, both which are a potential stimulus to macrophage functions, to the medium, MT-8 and MT-9 cells enhanced their histiocytic natures.(2) Cisplatin (anticancer drug)-resistant cell lines (MT-R8 and MT-R9) were induced from MT-8 and MT-9 cells, respectively. MT-R8 and MT-R9 cells enhanced both histiocytic and myofibroblastic natures, and further the tumors induced in syngeneic rats by MT-R9 cells showed a variety of histology : neoplastic proliferations of myofibroblasts and granular cells, osteosarcoma-like areas and areas involving many lipoblasts.(3) We investigated the origin of "histiocytic cells" in MFH and the immunophenotypes against ra … More t histiocyte-specific antibodies (ED1 and ED2). As a result, it was demonstrated that the presence of heterogeneities in the origin and immunophenotypes of the histiocytic cells.(4) Monoclonal antibodies against MT-8 cells were produced, and the staining patterns were immunohistochemically investigated. It was clarified that there are common antigens between MFH cells and undifferentiated mesenchymal cells or macrophage liniage cells, indicating the heterogeneity in cell natures of MFH-constituting cells.(5) We established transplantable tumors and cell lines from histiocytic sarcoma, fibrosarcoma and malignant meningioma in rats, and made comparisons of cell natures between MFH cells and these mesenchymal cell lines. The results indicated marked differences in biological natures between MFH and other mesenchymal tumor cells.(6) On the basis of these results, it was concluded that MFH consists of mesenchymal cells at various differentiation stages shifting from undifferentiated cells to cells with both histiocytic and fibroblastic natures ; the cellular natures could be easily changed, presumably depending on microenvironmental/genetic factors. MFH cells may be a mesenchymal progenitor with multipotential differentiation. The cell natures appear to contribute to endless, unstable histology of MFH.(7) Rat cell lines established in this study may provide useful experimental systems for studies on the histogenesis of MFH as well as mesenchymal differentiation yet undetermined. Less