EVIDENCE FOR MULTIPLE BINDING SITES FOR SEVERAL SPECIES OF HU IFN-ALPHA

几种化合物的抗增殖和竞争结合活性 HU类淋巴母细胞干扰素-α的纯化种类与 重组干扰素-α2b对Daudi和AU937细胞的作用我们 发现干扰素种类的抗增殖活性 每种细胞系的范围都很广，而且Daudi细胞更敏感 而不是AU937细胞。对细胞生长的抑制率为0.003。 对Daudi细胞的抑制率为10 ng/ml以上，对100 ng/ml的抑制率为1.2 ng/ml 在AU937细胞上。Scatchard分析表明，干扰素-α2b Daudi细胞上的结合位点数较大(12,700个结合位点数/细胞) AU937细胞(3,300个结合位点/细胞)；然而，它们的受体 亲和力也很相似。有趣的是，似乎有三个物种 (N，O，P)对这两种细胞都表现出最高的抗增殖活性 但不竞争干扰素-α-2b结合位点。 这些数据表明，可能存在不止一个或多个受体 参与这些分子生物学行为的受体成分。 为了进一步研究O-干扰素-α2b不同种间受体的差异 和其他物种，我们有放射性标记的物种O，并执行 竞争性绑定实验。我们还执行了交叉链接以 干扰素-α2b与物种O分子性质的比较研究 结合位点数。

The antiproliferative and competitive binding activities of several purified species of Hu lymphoblastoid Interferon-alpha were compared to that of recombinant Interferon-alpha 2b on Daudi and AU937 cells. We found that the antiproliferative activity of the interferon species on each cell line has a broad range and that Daudi cells were more sensitive than AU937 cells. The 50% inhibition of cell growth ranged from .003 ng/ml to greater than 10 ng/ml on Daudi cells and 1.2 ng/ml to >100 ng/ml on AU937 cells. Scatchard analyses demonstrated that the IFN-alpha 2b binding site number is greater on Daudi cells (12,700 binding sites/cell) than AU937 cells (3,300 binding sites/cell); however, their receptor affinities were similar. Interestingly, there appears to be three species (n,o,p) which exhibit the highest antiproliferative activities on both cell lines but do not compete for the Interferon-alpha-2b binding site. These data suggest that there may be more than one receptor or multiple receptor components involved in the biological actions of these molecules. In order to further study different receptors among species O IFN-alpha2b and other species, we have radiolabeled species O and performed competitive binding experiments. We also performed cross-linking to studies with IFN-alpha2b and species O to compare the molecular properties of the binding sites.