ONLY HIGH-AFFINITY RECEPTORS FOR INTERLEUKIN-2 MEDIATE INTERNALIZATION OF LIGAND
ONLY HIGH-AFFINITY RECEPTORS FOR INTERLEUKIN-2 MEDIATE INTERNALIZATION OF LIGAND
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DOI：
10.1073/pnas.83.5.1463
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发表时间：
1986-03-01
影响因子：
11.1
通讯作者：
KLAUSNER, RD
中科院分区：
文献类型：
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作者：
WEISSMAN, AM;HARFORD, JB;KLAUSNER, RD
白细胞介素2（IL-2）受体在活化的T细胞上和在选择的T细胞白血病中表达。最近，已经证明至少存在两类对配体具有显著不同亲和力的IL-2受体。所有已知的IL-2的生物学作用都与高亲和力位点的占据相关;低亲和力位点的功能仍然未知。受体介导的内吞作用是细胞表面受体及其配体内化的主要方式。在人T细胞淋巴细胞病毒1型（HTLV-1）感染的人T细胞白血病细胞系和克隆的鼠细胞毒性T细胞系（CTLL）中研究了结合于高亲和力和低亲和力受体位点的IL-2的内化。IL-2的内化仅在与高亲和力位点结合时发生。此外，抗受体抗体（抗-Tac），它同样很好地结合到高和低亲和力的网站，表现出不可检测的内化。这些发现的影响，因为它们涉及到IL-2受体的结构和功能进行了讨论。
Interleukin 2 (IL-2) receptors are expressed on activated T cells and in select T-cell leukemias. Recently, it has been demonstrated that at least two classes of receptor for IL-2 exist with markedly different affinities for ligand. All known biological actions of IL-2 have been correlated with occupancy of high-affinity sites; the function of the low-affinity sites remains unknown. Receptor-mediated endocytosis is the primary means of internalization of cell-surface receptors and their ligands. The internalization of IL-2 bound to high- and low-affinity receptor sites was studied in a human T-cell lymphocyte virus type 1 (HTLV-1)-infected human T-cell leukemia cell line and in a cloned murine cytotoxic T-cell line (CTLL). Internalization of IL-2 occurred only when bound to high-affinity sites. In addition, an anti-receptor antibody (anti-Tac), which binds equally well to high- and low-affinity sites, demonstrated no detectable internalization. The implications of these findings as they relate to IL-2 receptor structure and function are discussed.