Species Human Entrez 3553 | Human Mouse Ensembl ENSG00000125538 | |
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Aliases IL1B, IL-1, IL1-BETA, IL1F2, interleukin 1 beta External IDs OMIM: 147720 MGI: 96543 HomoloGene: 481 GeneCards: IL1B | ||
Interleukin 1 beta (IL1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the IL1B gene. There are two genes for interleukin-1 (IL-1): IL-1 alpha and IL-1 beta (this gene). IL-1β precursor is cleaved by cytosolic caspase 1 (interleukin 1 beta convertase) to form mature IL-1β.
Contents
Function
The fever-producing property of human leukocytic pyrogen (interleukin 1) was purified by Dinarello in 1977 (PNAS) with a specific activity of 10–20 nanograms/kg. In 1979, Dinarello reported that purified human leukocytic pyrogen was the same molecule that was described by Igal Gery in 1972. He named it lymphocyte-activating factor (LAF) because it was a lymphocyte mitogen. It was not until 1984 that interleukin 1 was discovered to consist of two distinct proteins, now called interleukin-1 alpha and interleukin-1 beta.
IL-1β is a member of the interleukin 1 family of cytokines. This cytokine is produced by activated macrophages as a proprotein, which is proteolytically processed to its active form by caspase 1 (CASP1/ICE). This cytokine is an important mediator of the inflammatory response, and is involved in a variety of cellular activities, including cell proliferation, differentiation, and apoptosis. The induction of cyclooxygenase-2 (PTGS2/COX2) by this cytokine in the central nervous system (CNS) is found to contribute to inflammatory pain hypersensitivity. This gene and eight other interleukin 1 family genes form a cytokine gene cluster on chromosome 2.
Properties
The molecular weight of the proteolytically processed IL1B is 17.5 kDa. IL1B has the following amino acid sequence:
The physiological activity determined from the dose dependent proliferation of murine D10S cells is 2.5 x 108 to 7.1 x 108 units/mg.
Clinical significance
Increased production of IL-1B causes a number of different autoinflammatory syndromes, most notably the monogenic conditions referred to as CAPS, due to mutations in the inflammasome receptor NLRP3 which triggers processing of IL-1B.
Intestinal dysbiosis has been observed to induce osteomyelitis through a IL-1β dependent manner.
Therapies targeting interleukin 1 beta
Canakinumab is a human monoclonal antibody targeted at IL-1B, and approved in many countries for treatment of cryopyrin-associated periodic syndromes.
Orthographic note
Because many authors of scientific manuscripts make the minor error of using a homoglyph, sharp s (ß), instead of beta (β), mentions of "IL-1ß" [sic] often become "IL-1ss" [sic] upon automated transcoding (because ß transcodes to ss). This is why so many mentions of the latter appear in web search results.