Introduction Interleukin-1α (IL-1α) is a member of the IL-1 superfamily containing IL-1α, IL-1β, and IL-1Ra receptor antagonist. IL-1α is known as hematopoietin (IL-1F1) and IL-1β as catabolin (IL-1F2). IL-1α and IL-1β correspond to two different isoelectric forms, acidic pI 5 and neutral pI 7, respectively. IL-1α has a molecular mass of 17 kDa and consists of 159 amino acids having 26 - 33% homology with IL-1β (1 - 6). They are produced mainly by macrophages and monocytes, processed and released during apoptosis, and bind with high affinity to specific receptors on target cells. While only the mature form of IL-1β has biological activity, both the pro and mature forms of IL-1α are active (7). IL-1α and IL-1β are pro-inflammatory cytokines involved in immune responses, inflammatory reactions, and hematopoiesis (8 - 9). IL-1α is an epidemal cytokine that is constitutively produced by epithelial cells and plays an important role in the maintenance of skin barrier function (10). The polymorphism of increased IL-1 production in patients is associated with rheumatoid arthritis, coagulation, solid tumors, leukemias, Alzheimer’s disease, autoimmune disorders, and myocardial infarction (11).
Principle of the Assay The AssayMax Human Interleukin-1α ELISA (Enzyme-Linked Immunosorbent Assay) kit is designed for detection of human IL-1α in plasma, serum, and cell culture supernatants. This assay employs a quantitative sandwich enzyme immunoassay technique, which measures IL-1α in less than 5 hours. A murine monoclonal antibody specific for IL-1α has been pre-coated onto a microplate. IL-1α in standards and samples is sandwiched by the immobilized antibody and a biotinylated polyclonal antibody specific for IL-1α, which is recognized by a streptavidin-peroxidase conjugate. All unbound material is then washed away and a peroxidase enzyme substrate is added. The color development is stopped and the intensity of the color is measured.