GAMMA INTERFERON RECEPTOR ON TUMORILYTIC MACROPHAGES

拟议研究的长期目标是了解伽马是如何 干扰素受体参与巨噬细胞活化的调节 用来杀死肿瘤细胞。作出建议的理据 研究表明，小鼠干扰素(MuIFN-Gamma)是一种形式 巨噬细胞激活因子，通过膜介导其作用 受体。因此，对受体的研究应该会产生 与识别早期事件相关的信息，这些事件 参与巨噬细胞活化的诱导。是否可以使用 来自基因泰克公司的大量重组小鼠伽马干扰素， 以及同质的培养巨噬细胞群体使这些 研究是可行的。它们将包括：(1)受体结合研究， 设计用来量化干扰素-γ的数量和结合亲和力 未受刺激的巨噬细胞上的受体，以及那些 对干扰素-γ(炎性巨噬细胞)或 反应性减弱(细胞溶解后巨噬细胞)。计算机辅助 Scatchard图的分析(配基程序)将是主要的方法 在此；(2)从巨噬细胞中富集干扰素-γ受体复合体 带或不带化学交联的膜；(3)制备 抗该受体的单抗。这些单抗 将被用来免疫纯化受体，以及确定 抗受体抗体结合或不结合可以在功能上模拟结合 干扰素-γ；(4)部分理化生化 分离的干扰素-γ受体的鉴定。如果时间允许， 将进行其他研究，以初步确定 与其功能类型有关的受体。一般迹象如下 到函数式类型，那么就可以设计明确的 研究将显示受体如何启动诱导 激活。这项拟议的研究意义重大，因为它将产生 关于一种重要的宿主防御机制的新的基本信息， 巨噬细胞激活以杀伤肿瘤细胞。预计大部分 所获得的知识将同样适用于理解 干扰素-γ调节多种其他巨噬细胞特性，并 功能，从诱导抗病毒状态到吞噬细胞或 抗原呈递。据我们所知，这将是对 巨噬细胞上的干扰素受体。(Hf)

The long range goal of the proposed research is to learn how the gamma interferon receptor is involved in the regulation of macrophage activation for tumor cell killing. The rationale for undertaking the proposed research is that murine gamma interferon (MuIFN-gamma), which is one form of macrophage activating factor, mediates its effects through a membrane receptor. Investigation of the receptor should, therefore, yield information that is pertinent to identifying the early events that are involved in the induction of macrophage activation. The availability of large amounts of recombinant murine gamma interferon from Genentech Inc., as well as homogenous populations of cultured macrophages have made these studies feasible. They will include: (1) receptor binding studies, designed to quantify the number and binding affinity of MuIFN-gamma receptors on unstimulated macrophages, as well as those with either increased responsiveness to MuIFN-gamma (inflammatory macrophages) or diminished responsiveness (postcytolytlc macrophages). Computer-assisted analysis (LIGAND program) of Scatchard plots will be the principal approach here; (2) enrichment of the MuIFN-gamma receptor complex from macrophage membranes, either with or without chemical crosslinking; (3) preparation of monoclonal antibodies against the receptor. These monoclonal antibodies will be used to immunopurify the receptor, as well as to determine whether or not antireceptor antibody binding can functionally mimic binding of MuIFN-gamma; and (4) partial physicochemical and biochemical characterization of the isolated MuIFN-gamma receptor. If time allows, additional studies will be performed to preliminarily characterize the receptor with regard to its functional type. With general indications as to the functional type, it should then be possible to design definitive studies that will show how the receptor initiates the events that induce activation. The proposed research is significant because it will yield new, basic information about an important host defense mechanism, macrophage activation for tumor cell killing. It is expected that much of the knowledge obtained will be equally applicable to understanding how MuIFN-gamma modulates a variety of other macrophage characteristics and functions, ranging from induction of an antiviral state to phagocytes or antigen presentation. To our knowledge, these will be the first studies of the gamma interferon receptor on macrophages. (HF)