Soluble cytokine receptor interleukin

For some cytokine receptors, including the growth hormone receptor and several interleukin receptors, soluble isoforms have been described that comprise all or part of the extracellular domain and may be able to bind the extracellular ligands. By association with other subunits of heterooligomeric receptors, e. g., the gpl30 subunit, these soluble isoforms can function as agonists or antagonists. 

H. Tilg, E. Trehu, M. B. Atkins, C. A. Dinarello, and J. W. Mier, Interleukin-6 (IL-6) as an Anti-Inflammatory Cytokine Induction of Circulating IL-1 Receptor Antagonist and Soluble Tumor Necrosis Factor Receptor p55, Blood. 8 (1994) 113-118. 

The authors speculated that the most likely explanation for these observations was linked to the lack of transfer of high-molecular weight soluble receptors and IgG across the blood-brain barrier, implying that control of brain tumor necrosis factor alfa cannot be obtained with monoclonal antibodies. They thought that neurological complications in diseases other than multiple sclerosis might be related to control of tumor necrosis factor alfa in the periphery, resulting in an enhanced contribution of brain-derived tumor necrosis factor alfa or other cytokines, such as interleukin-1. 

The functional modulation of the effect of cytokines requires the presence of cellular and soluble receptors. The expression of these receptors is regulated by specific signals, often dependent on cytokine networks. Transiently produced and of short half-life, cytokines are typically not stored as preformed molecules, and their production is dependent on transient genetic transcriptional activation and short-lived messenger ribonucleic acid (mRNA). Cytokines are rapidly secreted, leading to a brief burst of cytokine release. This burst is very important for cytokines to achieve distant activities, contrasting with the small amount of these molecules necessary for local functions (see later section on interleukin-1). 

Van der Poll T, Malefyt RW, Coyle SM, Lowry SF. Antiinflammatory cytokine responses during chnical sepsis and experimental endotoxemia Sequential measurements of plasma soluble interleukin (IL)-1 receptor type II, IL-10, IL-13. J Infect Dis 1997 175 118-122. 

Matsumiya, T., Imaizumi, T., Fujimoto, K., Cui, X., Shibata, T., Tamo, W., Kumagai, M., Tanji, K., Yoshida, H., Kimura, H., and Satoh, K. (2001). Soluble interleukin-6 receptor a inhibits the cytokine-induced fractalkine/CX3CLI expression in human vascular endothelial cells in culture. Exp. Cell Res. 269, 35-41. 

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