Role of Common-Gamma Chain Cytokines in NK Cell Development and Function: Perspectives for Immunotherapy

<table>Different mechanisms of IL-15 action. (a): Low levels of secreted IL-15 can bind to high affinity trimeric receptors through a juxtacrine mechanism. (b): IL-15 binds to the high-affinity IL-15R<i>α</i> chain within the endoplasmic reticulum and is then shuttled to the cell membrane as a complex. (c): IL-15R<i>α</i> can trans-present IL-15 to an apposing IL-2R<svg height="19.2875" id="M1" style="vertical-align:-4.15506pt" version="1.1" viewbox="0 0 38.587502 19.2875" width="38.587502" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> NK cell through cell contact. (d): The possibility of cis-presentation by IL-15R<i>α</i>/IL-15 membrane complex to an IL-2R<i>β</i>/<i>γ </i><sub>c</sub> heterodimer on the same NK cell is shown. (e): A soluble sushi domain-IL-15R<i>α</i> bound to IL-15 can perform trans-presentation in a soluble form. (f): Soluble IL-15R<i>α</i> extracellular domain generated by metalloprotease cleavage can bind soluble IL-15 and block its function.</table>

BioMed Research International

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Figure 2

Figure 2: Role of Common-Gamma Chain Cytokines in NK Cell Development and Function: Perspectives for Immunotherapy 