Interleukin 6 (IL-6) has a broad effect on cells of the immune system and those not of the immune system and often displays hormone-like characteristics that affect homeostatic processes. IL-6 has context-dependent pro- and anti-inflammatory properties and is now regarded as a prominent target for clinical intervention. However, the signaling cassette that controls the activity of IL-6 is complicated, and distinct intervention strategies can inhibit this pathway. Clinical experience with antagonists of IL-6 has raised new questions about how and when to block this cytokine to improve disease outcome and patient wellbeing. Here we discuss the effect of IL-6 on innate and adaptive immunity and the possible advantages of various antagonists of IL-6 and consider how the immunobiology of IL-6 may inform clinical decisions.
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S.A.J. has received funding support from Hoffman-La Roche, Ferring Pharmaceuticals and NovImmune and during the past 5 years has acted as an advisory consultant for Roche, Chugai Pharmaceuticals, NovImmune, Genentech, Sanofi Regeneron, Johnson & Johnson, Janssen Pharmaceuticals, Eleven Biotherapeutics and UCB. C.A.H. has received support from Amgen, Johnson & Johnson, and Janssen Pharmaceuticals, has acted as an advisory consultant for Medimmune and Biogen and is a member of the scientific advisory board of Surface Oncology.
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Hunter, C., Jones, S. IL-6 as a keystone cytokine in health and disease. Nat Immunol 16, 448–457 (2015). https://doi.org/10.1038/ni.3153
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