IL-1 refers to two proteins, IL-1α and IL-1β which are the products of distinct genes, but which are recognized by the same cell surface receptors. IL-1 binds to the cell surface type I and II IL-1 receptors (IL-1RI and IL-1RII). IL-1α, IL-1β, and IL-1RA can compete for binding to these receptors. IL-1 is a pyrogen, and it is an activating factor for lymphocytes. It also damages joints and influences liver proteins.The BioLegend ELISA MAX? Deluxe Set is a sandwich Enzyme-Linked Immunosorbent Assay (ELISA). A human IL-1α specific mouse monoclonal antibody is first coated on a 96-well plate. Standards and samples are added to the wells, and IL-1α binds to the immobilized capture antibody. Next, a biotinylated goat polyclonal anti-human IL-1α detection antibody is added, producing an antibody-antigen-antibody “sandwich”. Avidin horseradish peroxidase is subsequently added, followed by TMB Substrate Solution, producing a blue color in proportion to the concentration of IL-1α present in the sample. Finally, the Stop Solution changes the reaction color from blue to yellow, and the microwell absorbance is read at 450 nm with a microplate reader.