Abstract
IL-2Ralpha augments IL-2 signaling. Although this is generally believed to occur only when the three known components of IL-2R are associated within a single cell membrane, we demonstrate here an intercellular interaction. Cocultivation of cells individually expressing chimerae incorporating the extracellular domain of IL-2Ralpha alone with cells expressing chimerae of IL-2Rbeta alone permitted IL-2 dose-dependent oligomerization of the chimerae. Likewise, native IL-2Ralpha-bearing cells augmented the IL-2 proliferative response of ex vivo large granular lymphocytic leukemia cells expressing IL-2Rbeta/gamma(c) but lacking IL-2Ralpha. In both cases, the response was inhibitable by an Ab to IL-2Ralpha. Intercellular augmentation of cytokine effects, acting in trans, has important implications for biology and medicine.
MeSH terms
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Adjuvants, Immunologic / physiology*
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Antigen Presentation* / genetics
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Antigens, Polyomavirus Transforming / genetics
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Cell Communication / genetics
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Cell Communication / immunology
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Cell Line
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Coculture Techniques
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Humans
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Interleukin-2 / immunology*
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Interleukin-2 / metabolism*
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Intracellular Fluid / metabolism
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Jurkat Cells
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Leukemia, Lymphoid / metabolism
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Lymphocyte Activation
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Membrane Proteins / genetics
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Receptors, Antigen, T-Cell / genetics
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Receptors, Interleukin-2 / genetics
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Receptors, Interleukin-2 / metabolism*
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Recombinant Fusion Proteins / metabolism
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Signal Transduction / genetics
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Signal Transduction / immunology*
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T-Lymphocytes / metabolism
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T-Lymphocytes / radiation effects
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Transfection / immunology
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Tumor Cells, Cultured
Substances
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Adjuvants, Immunologic
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Antigens, Polyomavirus Transforming
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Interleukin-2
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Membrane Proteins
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Receptors, Antigen, T-Cell
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Receptors, Interleukin-2
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Recombinant Fusion Proteins
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antigen T cell receptor, zeta chain