This IgG fraction antibody of anti-Human IL-1 Receptor Type II (IL-1RII) has been tested for use in ELISA, radioimmunoassays, flow cytometry, immunoblot, and immunoprecipitation. Reactivity in other immunoassays is unknown. IL-1RII has been termed p68 or CD121 in some laboratories. IL-1RII has been shown to bind IL-1, IL-1a and IL-1b. This product has been assayed for the ability to immunoprecipitate antigen. A dilution range of 1:400 to 1:800 is suggested for this immunoassay. For immunoprecipitation, pre-clearing with a non-specific rabbit IgG is helpful to reduce background. This product has been assayed by immunoblot using HRP Goat-anti-Rabbit IgG [H&L] (code # 611-1302) and TMB as a substrate. A working dilution range of 1:200 to 1:400 is suggested for this application. This product has been assayed by ELISA against soluble (extracellular) IL-1RII using HRP Conjugated Anti-Rabbit IgG [H&L] (Goat) (code # 611-1302) and ABTS as a substrate for 30 minutes at room temperature. A working dilution range of 1:1,000 to 1:2000 is suggested for this product. For use in ELISA formats, this antibody is best used as the second antibody in combination with a monoclonal antibody as a capture antibody. This product has been assayed by radioimmunoassay against antigen. A dilution of 1:8,000 is suggested for this immunoassay.