Interleukin 1 alpha (IL-1a) is expressed by epithelial cells, activated macrophages, neutrophils, and endothelial cells to regulate immune responses. IL-1a signals through the IL-1 receptor, type 1 (IL-1R1) to activate the myeloid differentiation primary response 88 (MYD88) signaling pathway, which contains the cytoplasmic Toll/IL-1 receptor (TIR) domain adapter. IL-1a and the independently regulated IL-1ß protein have overlapping proinflammatory activities to induce adhesion molecule expression on epithelial cells, control fever induction, initiate rheumatoid arthritis, and promote septic shock.
Bioactivity Assay:D10.G4.1 cell proliferation; ED50 =0.05 ng/mL; Bioactivity =2.0 x 10^7 units/mg