Pfeffer L M, Stebbing N, Donner D B
Proc Natl Acad Sci U S A. 1987 May;84(10):3249-53. doi: 10.1073/pnas.84.10.3249.
Human Daudi lymphoblastoid cells, which are highly sensitive to the antiproliferative action of human leukocyte alpha-interferon (IFN-alpha), and IFN-resistant and IFN-sensitive Daudi subclones (Cl2 and Cl1, respectively), contain 2300 (Kd = 20 X 10(-12) M), 3000 (Kd = 45 X 10(-12) M), and 3700 (Kd = 52 X 10(-12) M) IFN-alpha binding sites per cell, respectively. Thus, these IFN-sensitive and IFN-resistant cells have similar numbers of high-affinity IFN-alpha receptors. IFN-receptor complexes that are insoluble in Triton X-100 accumulate in IFN-sensitive but not in IFN-resistant cells. The ligand-induced accumulation of Triton-insoluble complexes in IFN-sensitive cells was inhibited by cytochalasin B. This suggests that the solubility change of IFN-receptor complexes results from their interaction with the cytoskeletal matrix. The dissociation of IFN-alpha from IFN-sensitive and IFN-resistant cells can be resolved into fast and slow components. IFN-alpha dissociates more slowly from IFN-sensitive cells than from IFN-resistant cells. Very slow dissociation of IFN-alpha from Triton-insoluble complexes correlates with this difference. These observations suggest that IFN-receptor complexes become coupled to the cytoskeletal matrix in IFN-sensitive but not in IFN-resistant cells, and that such interaction is an important element in the mechanism of the antiproliferative action of IFN-alpha on Daudi cells.
人Daudi淋巴母细胞对人白细胞α-干扰素（IFN-α）的抗增殖作用高度敏感，以及IFN抗性和IFN敏感的Daudi亚克隆（分别为Cl2和Cl1），每个细胞分别含有2300个（Kd = 20×10⁻¹² M）、3000个（Kd = 45×10⁻¹² M）和3700个（Kd = 52×10⁻¹² M）IFN-α结合位点。因此，这些IFN敏感和IFN抗性细胞具有相似数量的高亲和力IFN-α受体。不溶于Triton X-100的IFN受体复合物在IFN敏感细胞中积累，而在IFN抗性细胞中不积累。细胞松弛素B抑制了IFN敏感细胞中配体诱导的Triton不溶性复合物的积累。这表明IFN受体复合物的溶解度变化是由于它们与细胞骨架基质的相互作用。IFN-α从IFN敏感和IFN抗性细胞中的解离可分为快速和慢速成分。IFN-α从IFN敏感细胞中的解离比从IFN抗性细胞中更慢。IFN-α从Triton不溶性复合物中非常缓慢的解离与这种差异相关。这些观察结果表明，IFN受体复合物在IFN敏感细胞中与细胞骨架基质偶联，而在IFN抗性细胞中则不然，并且这种相互作用是IFN-α对Daudi细胞抗增殖作用机制中的一个重要因素。
