Interleukin 1 (IL-1) is essentially a family of proteins, which includes IL-1a, IL-1a, IL-1RA (interleukin 1 receptor antagonist), IL-18, and IL-33.
IL-1b is synthesized as a 269-amino acid pro-cytokine which is then enzymatically cleaved to its active form with a molecular weight of 17 kDa (154 amino acids). IL-1b is produced by many cell types including macrophages, monocytes, astrocytes, epithelial and endothelial cells, keratinocytes, adipocytes, smooth muscle fibers, T cells, and eosinophils. Although IL-1a and IL-1b show only 27% homology to their amino acids, they bind to the same cellular receptors, IL-1 RI (CD121a, mainly in T cells), and IL-1 RII (CD121b, mainly in B-lymphocytes, neutrophils, and macrophages), which are found in a variety of cells involved in immune or inflammatory reactions. Normal production of IL-1 is critical for mediating the body's responses to infections and injuries.
IL-1 is usually not produced by unstimulated cells of healthy individuals with the exception of keratinocytes, some epithelial cells, and some cells of the central nervous system. However, in response to various inflammatory factors, infections, or microbial endotoxins, a very large increase in the production of IL-1 by macrophages and various other cell types occurs. IL-1 plays a central role in immune and inflammatory responses, bone remodeling, fever, carbohydrate metabolism, and growth hormone physiology (GH/IGF-I). Inappropriate or prolonged production of IL-1 has been observed in a variety of pathological conditions, including sepsis, rheumatoid arthritis, inflammatory bowel diseases, acute and chronic myelogenous leukemia, insulin-dependent diabetes mellitus, arteriosclerosis, neuronal damage, and in diseases related to the aging of the organism.
Elevated levels of IL-1b have been found in various infections and non-infectious inflammatory conditions, such as Crohn's disease. In addition to elevated serum levels, IL-1b has been found in the synovial fluid of rheumatoid arthritis patients and in the cerebrospinal fluid following inflammation of the nervous system. On the other hand, low levels of IL-1b have been found in malnutrition and advanced tumors.
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.
