Interleukin-18 (IL-18) is cytokine that plays a role in regulating immune responses.
It is produced by various immune cells, including macrophages and dendritic cells, as well as non-immune cells like epithelial cells.
It stimulates the production of interferon-gamma (IFN-gamma), which is an important cytokine involved in immune responses against infections, autoimmune diseases, and cancer.
Like IL-12, IL-18 also promotes the differentiation of T helper type 1 (Th1) cells and enhances their ability to secrete IFN-gamma.
Additionally, IL-18 contributes to the activation of natural killer (NK) cells, promoting their cytotoxicity against infected or cancerous cells.
It contributes to the maturation and activation of dendritic cells, enhancing their antigen-presenting abilities.
IL-18 has been studied in various disease contexts, including inflammatory conditions like rheumatoid arthritis, inflammatory bowel disease, and certain types of cancer.
IL-18 stimulates IFN-γ production by T cells and NK cells.
It acts either independently or synergizes with IL-12, promoting activation of the monocyte / macrophage system.
IL-18 and IL-12 inhibits IL-4 dependent production of IgE and IgG1 and, in turn, promotes IgG2 production by B cells.
IL-18 is involved in several serious inflammatory reactions.
The amount of IL-18 receptor mRNA in the endometrium as well as the ratio of the amount of binding protein to interleukin is demonstrably increased in patients with endomyosis compared to individuals without endomyosis.
IL-18 is also amplified in Hashimoto’s thyroiditis.
This interleukin has been shown to increase β amyloid production in neurons in Alzheimer’s disease.