cy·​to·​kine | \ ˈsī-tə-ˌkīn How to pronounce cytokine (audio) \
plural cytokines

Definition of cytokine

: any of a class of immunoregulatory proteins (such as interleukin or interferon) that are secreted by cells especially of the immune system Most cytokines are produced primarily in the presence of disease or immunization and contribute to immune responses, inflammation, and endothelial cell activation; others are involved in tissue repair.— Charles A. Dinarello et al. The proinflammatory cytokine interleukin-2 determines the magnitude and duration of the T-cell response immediately after antigen encounter and assists in the maturation of macrophages and the proliferation of B cells and natural killer cells …— Chiea C. Khor et al.

Examples of cytokine in a Sentence

Recent Examples on the Web Other patients suffer cytokine release syndrome, where chemicals released by the immune system lead can cause extremely high fevers, nausea, muscle and joint pain and even organ damage. Karen Weintraub, USA TODAY, 2 Feb. 2022 Another side effect is cytokine release syndrome, which gives people a severe flu-like syndrome, with very high fevers, nausea, vomiting, and muscle and joint pain. Jacqueline Howard And Carma Hassan, CNN, 2 Feb. 2022 The lethal version detects cells that have been infected with a virus, then kills them (by releasing a toxic version of a granule called a cytokine) to stop the virus from replicating. Los Angeles Times, 19 Jan. 2022 Several targeted therapies focus on a particularly powerful cytokine called tumor necrosis factor, or TNF. Marla Broadfoot, Scientific American, 1 Sep. 2021 Each works by preventing a particular cytokine from causing inflammation. Stephanie Watso, SELF, 27 Aug. 2021 For now, the cytokine sensing part of the device needs to be replaced daily. Dallas News, 16 July 2021 The drug stimulates an immune receptor that controls how much cytokine is produced. Elizabeth Cooney, STAT, 12 Nov. 2020 With a powerful 1-2-3 punch, these cells eliminate the virus, calm the immune overreaction known as a cytokine... Kevin Kimberlin, WSJ, 13 Aug. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cytokine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cytokine

1974, in the meaning defined above

History and Etymology for cytokine

cyt- + -kine (as in lymphokine)

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Time Traveler for cytokine

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The first known use of cytokine was in 1974

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Dictionary Entries Near cytokine



cytokine release syndrome

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Last Updated

17 Apr 2022

Cite this Entry

“Cytokine.” Dictionary, Merriam-Webster, Accessed 27 May. 2022.

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More Definitions for cytokine


cy·​to·​kine | \ ˈsīt-ə-ˌkīn How to pronounce cytokine (audio) \

Medical Definition of cytokine

: any of a class of immunoregulatory proteins (as interleukin, tumor necrosis factor, and interferon) that are secreted by cells especially of the immune system

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