Dietsch M T, Smith V F, Cosand W L, Damle N K, Ledbetter J A, Linsley P S, Aruffo A
Bristol-Myers Squibb Pharmaceutical Research Institute, Seattle, WA 98121.
J Immunol Methods. 1993 Jun 4;162(1):123-32. doi: 10.1016/0022-1759(93)90414-3.
In recent years the functional consequences of receptor/ligand interactions have been studied in vitro and in vivo using monospecific recombinant immunoglobulin fusion proteins (recombinant/receptor globulins, Rg). These proteins are encoded by chimeric genes composed of a DNA fragment encoding the extracellular domain of a cell surface protein grafted onto a DNA fragment encoding immunoglobulin constant domains. In order to extend the range of applications of Rgs we investigated the possibility of preparing bispecific Rgs. These bispecific fusion proteins contain the extracellular domains of two cell surface proteins held together in close proximity by the constant domains of an immunoglobulin. Here we describe the preparation and characterization of a bispecific Rg which contains the extracellular domains of two adhesion molecules expressed by activated vascular endothelial cells, E-selectin and P-selectin. These two proteins play an important role in initiating leukocyte adhesion to the vascular cell wall at sites of inflammation. Binding studies showed that the E-selectin/P-selectin bispecific immunoglobulin fusion protein (ELAM-1/GMP140 Rg) has an enhanced ability to bind to the myeloid cell line HL60 when compared to the monospecific Rg fusion proteins from which it was derived.
近年来，利用单特异性重组免疫球蛋白融合蛋白（重组/受体球蛋白，Rg）在体外和体内研究了受体/配体相互作用的功能后果。这些蛋白质由嵌合基因编码，该嵌合基因由编码细胞表面蛋白胞外域的DNA片段嫁接到编码免疫球蛋白恒定域的DNA片段组成。为了扩展Rg的应用范围，我们研究了制备双特异性Rg的可能性。这些双特异性融合蛋白包含两种细胞表面蛋白的胞外域，它们通过免疫球蛋白的恒定域紧密结合在一起。在此，我们描述了一种双特异性Rg的制备和特性，它包含活化血管内皮细胞表达的两种黏附分子E-选择素和P-选择素的胞外域。这两种蛋白在炎症部位启动白细胞与血管细胞壁的黏附中起重要作用。结合研究表明，与它所衍生的单特异性Rg融合蛋白相比，E-选择素/P-选择素双特异性免疫球蛋白融合蛋白（ELAM-1/GMP140 Rg）与髓系细胞系HL60的结合能力增强。
