PHYSICAL CHEMISTRY OF THERAPEUTIC PLASMA PROTEINS

我们建议继续研究其结构、稳定性和分子结构， 选择的人血浆蛋白的相互作用。 其中包括（1） 纤连蛋白是一种多结构域糖蛋白， 大分子并介导各种细胞与表面的附着， (2)补体C1，一种大型多亚基组装体，其激活触发 一个复杂的宿主防御反应，（3）C1-抑制剂，蛋白酶抑制剂 其调节活性C1的水平，和（4）抗凝血酶III，另一种 凝血级联中几种蛋白酶的抑制剂。 光谱技术，特别是荧光，将用于 研究功能上的动力学和/或平衡方面 重要的蛋白质-蛋白质相互作用如纤连蛋白/胶原， 纤连蛋白/肝素、C1-抑制剂/C1和各种亚组分之间 Cl（Clq，Clr和Cls）。 同样的技术将用于检测 并表征这些蛋白质的结构转变， 各种形式的应力（热、变性剂、pH）。 将努力 识别独立展开的结构域，并在可行的情况下分离它们 从亲本蛋白质的酶促酶解物中分离，并进一步表征它们 在稳定性和互动方面。 差示扫描量 量热法将用于热变性的研究， 将与在相同条件下进行的光谱测量相关联。 条件 我们将继续寻求治疗条件， 血浆蛋白可以经受巴氏灭菌或其它处理， 为了选择性地抑制潜在的传染因子（肝炎病毒， HTLV III），可能会污染临床制剂。 除了一 更好地了解结构和功能，我们的研究可能会导致 确定新的相互作用，以更好地了解 这些蛋白质在病理条件下的安全性和改善的安全性， 来自人血浆的输血产品。

We propose continued research into the structure, stability, and molecular interactions of selected human plasma proteins. These include (1) fibronectin, a multidomain glycoprotein which interacts with numerous macromolecules and mediates the attachment of various cells to surfaces, (2) complement C1, a large multisubunit assembly whose activation triggers an elaborate host-defense reaction, (3) C1-Inhibitor, a protease inhibitor which regulates the levels of active C1, and (4) antithrombin III, another inhibitor of several proteases in the blood clotting cascade. Spectroscopic techniques, especially fluorescence, will be used to investigate the kinetic and/or equilibrium aspects of functionally important protein-protein interactions such as fibronectin/collagen, fibronectin/heparin, C1-Inhibitor/C1 and between the various subcomponents of Cl (Clq, Clr, and Cls). These same techniques will be used to detect and characterize structural transitions of these proteins in response to various forms of stress (heat, denaturants, pH). Efforts will be made to identify independently unfolding domains and, where feasible, isolate them from enzymatic digests of the parent protein and further characterize them with respect to stability and interactions. Differential scanning calorimetry will be used in studies of thermal denaturation and results will be correlated with spectral measurements made under identical conditions. We will continue to seek conditions under which therapeutic plasma proteins can withstand pasteurization or other treatment, designed to selectively inactivate potentially infectious agents (hepatitis viruses, HTLV III) which might contaminate clinical preparations. In addition to a better understanding of structure and function, our studies may lead to the identification of new interactions, to a better understanding of the role of these proteins in pathological conditions and to the improved safety of transfusion products derived from human plasma.