Interleukin-1 alpha

Interleukin-1 alpha (IL-1 alpha, IL-1a) is a soluble protein produced by monocytes, macrophages, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. IL-1 consists of two distinct forms, IL-1 alpha and IL-1 beta, which perform the same functions but are distinct proteins. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation. Interleukin-1 alpha is a potent immuno-modulator which mediates a wide range of immune and inflammatory responses. Peripheral blood mononuclear cells of patients with aplastic anemia show markedly decreased IL-1 production. Aplastic patients with low IL-1 production are distinguished by the severity of their disease and the degree of neutropenia while myelodysplastic patients with comparable degrees of pancytopenia have normal IL-1 production. It has been shown that IL-1 also promotes wound healing. This activity is thought to involve effects on angiogenesis, the promotion of fibroblast proliferation, and the chemotactic activity on neutrophils. Elevated amounts of IL-1 are found in the synovial fluid of patients with rheumatoid arthritis and osteoarthritis. IL-1 alpha may be a pathogenetic factor in the complex processes leading to vascular occlusion and an important in situ indicator of, and a potential participant in, vascular injury. It is consistently present in all vessels with sclerotic histopathologic changes following aortocoronary bypass grafting of saphenous veins and internal mammary arteries.

Swiss-Prot Accession Number: P01583