THERAPEUTIC USES FOR HUMAN GRANULOCYTE CSF

拟议的研究旨在建立一个实验基础， 人粒细胞集落刺激因子(hG-CSF)的应用 在恶性肿瘤患者的管理中，特别是 急性髓系白血病。这个因素是独一无二的，因为在 体外系统，它可以刺激正常人和 小鼠髓系细胞，并抑制生长(可能通过 诱导某些人和小鼠急性髓系细胞分化) 白血病(AML)细胞。最近克隆了一个hG-CSF基因， 而它在体外的表达已经导致了 重组因子，这是这些研究所必需的。 确定了三个主要的特异性靶点：1)一个新的G-CSF基因 将通过测序来表征来自LD1黑色素瘤系的， 它将在哺乳动物和细菌中表达 表达系统允许对其蛋白质进行表征 产品，并与其他G-CSF进行了比较。2)重组HG- 脑脊液将被用于研究其抑制或刺激作用 人急性髓系白血病细胞系(PLB-985、KG-1)和新鲜AML的生长 来自患者的原始细胞，以异种移植或扩散的形式生长 裸鼠的房间。支持性研究将定义 重组人粒细胞集落刺激因子在小鼠体内的药代动力学研究 包括破骨细胞激活引起的骨量减少，并在 体外筛选试验预测rhG-CSF对急性髓系白血病的影响 体内的细胞。这些后一种测试将包括体外培养和 125I标记的G-CSF与AML细胞的结合，癌基因 表达和自分泌产生CSF。之间的协同效应 重组人粒细胞集落刺激因子和其他分化剂(RA，1，25-OH-VD3， 米特拉霉素、阿霉素)也将在体外和#年寻求 活着。耐G-CSF的AML亚系(PLB-2R和KG-1a)将 通过逆转录病毒载体将G-CSF基因导入 探讨急性髓系白血病细胞G-CSF耐药的机制。 3)G-CSF改变体内骨髓毒性的能力，以及 提高细胞毒药物的治疗指数 白血病的治疗也将被检查。这些研究将是 用人(PLB985，KG-1)AML细胞系在裸鼠体内，以及 小鼠肿瘤株(L1210、Dunn骨肉瘤)。一种奇特的 阶段特定和非特定细胞毒性药物(MTX、ADR、CTX、 Arac)将与重组人粒细胞集落刺激因子一起或在重组人粒细胞集落刺激因子之后给小鼠。

The proposed studies seek to establish an experimental basis for the use of human granulocyte colony-stimulating factor (hG-CSF) in the management of patients with malignancies, particularly acute myelogenous leukemia. This factor is unique in that with in vitro systems, it can stimulate production of normal human and murine myeloid cells, and also inhibit the growth (possibly by inducing differentiation) of some human and murine acute myeloid leukemia (AML) cells. The recent cloning of a gene for hG-CSF, and its expression in vitro has led to the availability of recombinant factor, which is required for these studies. Three major specific aims are identified: 1) A new G-CSF gene from the LD1 melanoma line will be characterized by sequencing, and it will be expressed in both mammalian and bacterial expression systems to allows characterization of its protein product, and comparison with other G-CSFs. 2) recombinant hG- CSF will be used to study its supperssive or stimulatory effects on growth of human AML cells lines (PLB-985, KG-1) and fresh AML blasts from patients, growing as xenografts or in diffusion chambers in nude mice. Supporting studies will define the pharmacokinetics of rhG-CSF in mice, examine possible toxicity including osteopenia due to oseoclast activiation, and develop in vitro screening assays to predict the effect of rhG-CSF, on AML cells in vivo. These latter tests will include in vitro culture with G-CSF, binding of 125I-labelled G-CSF to AML cells, oncogene expression, and autocrine production of CSFs. Synergy between rhG-CSF and other differentiating agents (RA, 1,25-OH-VD3, mithramycin, adriamycin) will also be sought both in vitro and in vivo. A G-CSF-resistance AML subline (PLB-2R and KG-la) will be transfected with the G-CSF gene via a retroviral vector to characterize the mechanisms of G-CSF resistance in AML blasts. 3) The ability of G-CSF to modify the in vivo myelotoxicity, and to improve the therapeutic index of cytotoxic drugs used in leukemia treatment will also be examined. These studies will be used both human (PLB985, KG-1) AML lines in nude mice, and murine tumor lines (L1210, Dunn osteosarcoma). A specrum of phase specific and non-specific cytotoxic drugs (MTX, ADR, CTX, AraC) will be administrated with, or after rhG-CSF to mice.