EFFECTS OF A RECOMBINANT TOXIN TARGETED TO THE SMOOTH MUSCLE CELLS FF RECEPTOR

针对平滑肌细胞 FF 受体的重组毒素的作用

• 批准号: 3843414
• 负责人: S BIRO
• 金额: --
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 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/3843414
• 关键词: Pseudomonas; artery stenosis; cell growth regulation; cell migration; chimeric proteins; cytotoxicity; exotoxins; genetic manipulation; growth factor receptors; myoepithelial cell; tissue /cell culture; transforming growth factors; vascular endothelium; vascular smooth muscle

The dominant mechanism responsible for restenosis after angioplasty is believed to be the activation of medial smooth muscle cells (SMC), leading to their proliferation, migration to the subintima, and further proliferation. To develop novel strategies that might inhibit or prevent restenosis, we previously used a chimeric toxin composed of TGFalpha (which targets the EGF receptor) and mutated Pseudomonas exotoxin to preferentially recognize and kill rapidly proliferating, vs quiescent, vascular SMC. We have recently cloned and expressed a recombinant gene encoding Pseudomonas exotoxin with a mutated (nonfunctional) cell recognition domain fused with the ligand acidic FGF; thus, this recombinant toxin targets the FGF receptor. In the present study we evaluated the relative effects of this chimeric toxin on quiescent vs. rapidly proliferating vascular SMC, and also determined whether it exerted different effects on SMC vs. endothelial cells. Rapidly proliferating SMCs were very sensitive to its cytotoxic effects, whereas cytotoxicity was significantly less when the SMCs were in a quiescent state. The chimeric toxin was also significantly less cytotoxic against endothelial cells. Thus, these studies suggest a potentially expanded role of recombinant toxin therapy in restenosis: multiple receptors can be targeted, and cytotoxic effects, at least in vitro, can be preferentially directed to rapidly proliferating vascular SMC, with relative sparing of vascular endothelial cells.

血管成形术后再狭窄的主要机制是 据信是激活中膜平滑肌细胞(SMC)，导致 导致它们的增殖，迁移到内膜下，并进一步 扩散。开发可能抑制或预防的新策略 我们之前使用了一种由转化生长因子α组成的嵌合毒素 (靶向EGF受体)和突变的假单胞菌外毒素 优先识别并杀死快速增殖的、与静止的、 血管SMC。 我们最近克隆并表达了一个编码 具有突变(非功能)细胞识别功能的假单胞菌外毒素 结构域与配体酸性成纤维细胞生长因子融合；因此，该重组毒素 靶向成纤维细胞生长因子受体。在本研究中，我们评估了相对的 这种嵌合毒素对静止期和快速增殖期的影响 血管SMC，并测定其是否对血管内皮细胞 SMC与内皮细胞。快速增殖的SMC非常敏感 对其细胞毒性作用，而细胞毒性显著低于 SMC处于静止状态。嵌合毒素也是 对内皮细胞的细胞毒性显著降低。 因此，这些研究表明，重组人的作用可能会扩大。 毒素治疗再狭窄：可靶向多种受体，并 至少在体外，细胞毒作用可以优先针对 快速增殖的血管SMC，血管相对稀疏 内皮细胞。