MICROPHARMACOLOGY OF BIOLOGICAL LIGANDS

生物配体的显微药理学

• 批准号: 3774703
• 负责人: J N WEINSTEIN
• 金额: --
• 依托单位: DIVISION OF CANCER TREATMENT
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3774703
• 关键词: antineoplastics; autoradiography; chemical binding; chromophore; dosage; drug design /synthesis /production; drug screening /evaluation; guinea pigs; immunocytochemistry; ligands; metastasis; monoclonal antibody; neoplasm /cancer pharmacology; tissue /cell culture

There are a number of reasons why it is easier to kill cancer cells in culture than in solid tumors. One that has received relatively little attention is the problem of poor microscopic access. For a number of years, we have been exploring ways to integrate macroscopic and microscopic aspects of the pharmacology of biologically interesting ligands, principally to get at the problem of poor access. That work has centered on monoclonal antibodies but with an eye to correlates in the pharmacology of other biological ligands and low molecular weight agents. Theoretical: We first developed a CRAY supercomputer program package (PERC) that solves the differential equations for macroscopic and microscopic pharmacology. PERC has generated a number of unexpected predictions and assisted in the design of experiments. We formulated the "binding site barrier" hypothesis - i.e., that the very fact of successful binding to a target antigen, receptor, or transporter can limit penetration into the substance of a tumor. Calculations suggested that (i) the barrier effect could prevent penetration even 100-200 microns from a blood vessel; (ii) paradoxically, high affinity and high target density could lead to lower concentrations of ligand a few hundred microns from a vessel; (iii) increasing the dose of ligand involves a delicate balance of effects. We have now extended these calculations to two-step therapy, in which a slowly distributing ligand is chased by a fast-distributing ligand-effector chimera. Experimental: We recently obtained direct experimental verification of the binding site barrier hypothesis. With R. Neumann, et al. in the NM, CC, we examined bulk tumor and micrometastases of L10 carcinoma in guinea pigs. A combination of double-label autoradiography and double-chromophore immunohistochemistry detected simultaneously the distribution of antibody, control IgG, antigen, and blood vessels. Results in both s.c. tumors and micrometastases fit the hypothesis. The "binding site barrier" effect is probably a factor in the evolution of autocrine/paracrine molecules. As a corollary, the micropharmacology should be considered when designing molecules for exogenous administration or for secretion by genetically modified cells in viva Current work centers on the access problem in a new hollow fiber model for solid tumors that we are developing in collaboration with M. Hollingshead, J. Mayo, et al. (see Proj. #Z01 CM 07349-01).

有很多原因可以解释为什么在体外更容易杀死癌细胞。 比在实体瘤中的培养。一个相对来说 注意的是显微镜检查不佳的问题。由于多种 多年来，我们一直在探索如何将宏观和 药理学的微观方面， 配体，主要是为了解决难以获得的问题。这项工作 以单克隆抗体为中心， 其他生物配体和低分子量试剂的药理学。 理论：我们首先开发了一个CRAY超级计算机程序包 （PERC），解决了宏观和 微观药理学PERC已经产生了许多意想不到的 预测并协助设计实验。我们制定了 “结合位点屏障”假说-即，成功的事实 与靶抗原、受体或转运蛋白的结合可以限制 渗透到肿瘤的实质中。计算表明，（i） 阻挡层效应甚至可以防止从100-200微米的 血管;（ii）矛盾的是，高亲和力和高靶密度 可能导致配体浓度降低， （iii）增加配体的剂量涉及以下方面的微妙平衡： 方面的影响.我们现在已经将这些计算扩展到两步疗法， 其中缓慢分布的配体被快速分布的配体追赶， 配体效应嵌合体。 实验：我们最近获得了直接的实验验证， 结合位点屏障假说与R. Neumann等人在NM、CC中，我们 在豚鼠中检查L10癌的本体肿瘤和微转移。 双标记放射自显影和双发色团的组合 免疫组化同时检测抗体分布， 对照IgG、抗原和血管。两种s.c.结果肿瘤和 微转移符合假设 “结合位点屏障”效应可能是 自分泌/旁分泌分子。作为推论，微药理学 当设计用于外源施用的分子时， 或供转基因细胞在体内分泌 中心的访问问题，在一个新的中空纤维模型的实体肿瘤 我们正在与M.霍林斯黑德，J.马约等 al. (see项目。#Z01 CM 07349-01）。