interleukin-6

noun

in·​ter·​leu·​kin-6 ˌin-tər-ˈlü-kən-ˈsiks 

: an interleukin that is produced by various cells (such as macrophages, fibroblasts, T cells, and tumor cells) and that induces the maturation of B cells and growth of myeloma cells, activates and induces the proliferation of T cells, stimulates synthesis of plasma proteins (such as fibrinogen), and plays a role in producing fever

Last year, researchers discovered that older women who were socially active had lower levels of interleukin-6, a substance linked to chronic inflammation that is found at high levels in people with Alzheimer's disease, heart disease, and cancer.

—Andrew Weil

—abbreviation IL-6

Examples of interleukin-6 in a Sentence

Recent Examples on the Web

These responses saw inflammatory messengers like interleukin-6, interleukin-1β and tumor necrosis factor-alpha increasingly released. —New Atlas, 27 June 2025

The researchers then sought to gain a deeper understanding of the biology underlying the connection between melatonin secretion and ADHD symptoms by examining levels of the inflammatory messenger interleukin-6 (IL-6) in the children’s blood. —Paul McClure 09, New Atlas, 9 June 2025

Common blood tests that are markers of inflammation include C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-a). —Allison Herries, Verywell Health, 14 Jan. 2025

Studies show that regular omega-3 intake can reduce levels of inflammatory molecules associated with chronic inflammatory conditions, such as C-reactive protein (CRP) and interleukin-6 (IL-6). —Lindsay Curtis, Verywell Health, 13 Dec. 2024

With multiple myeloma, levels of the chemical messenger interleukin-6 (IL-6) increase. —Lindsay Curtis, Health, 1 Dec. 2024

Examples of those markers include interleukin-6 (IL-6) and C-reactive protein (hs-CRP) in people with conditions known to increase inflammation in the body, like type 2 diabetes.4 2. —Jillian Kubala, Health, 28 Oct. 2024

The nutrients in whole grains like bulgur wheat may help lower inflammatory markers such as interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factors (TNF). —Lauren O'Connor, Ms, Health, 2 Oct. 2024

This immune malfunction is typically accompanied by the release of inflammatory molecules called cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and granulocyte-macrophage colony-stimulating factor (GM-CSF). —Devineé Lingo, M.s., Rdn, Health, 6 Sep. 2024

Word History

First Known Use

1987, in the meaning defined above

Medical Definition

interleukin-6

noun

-ˈsiks 

: an interleukin that is produced by various cells (as macrophages, fibroblasts, T cells, and tumor cells) and that acts as a pyrogen, induces maturation of B cells and growth of myeloma cells, activates and induces proliferation of T cells, and stimulates synthesis of plasma proteins (as fibrinogen)

—abbreviation IL-6