Interleukin-1β （IL-1β） is a major cytokine involved in monocyte activation and activation of proinflammatory signaling pathways in peripheral tissues and brain. IL-1β expression and its secretion are tightly regulated. IL-1β is released by several cell types, including activated macrophages, monocytes, and cells within the hypothalamus, where it can stimulate its own expression.IL-1β is present and active in the luteinized ovary as shown by its expression in human granulosa lutein cells and in follicular fluid macrophages that are natural components of the corpus luteum tissue. IL-1β, its corresponding receptor antagonist Interleukin Receptor Antagonist-1 （IL-1RA）, and Interleukin 1 alpha （IL-1α） are encoded by the genes IL-1B, IL-1RN, and IL-1A respectively, as constituents of the Interleukin 1 （IL-1） gene cluster. IL-1β is a crucial candidate due to its dual role as both a proinflammatory signaling molecule and an inhibitor of gastric acid secretion. IL-1β can promote tumor growth, but also antitumor activities. The presence of IL-1β and other inflammatory cytokines also has been noted at an early phase of plaque formation in the brains of patients with Alzheimer's disease.