"The TRAIL R4 (Human) ELISA Kit is a solid phase sandwich ELISA for the in-vitro qualitative and quantitative determination of TRAIL R4/DcR2 in cell culture supernatants, buffered solutions or human serum, plasma, or other body fluids. This assay will recognize both natural and recombinant human TRAIL R4/DcR2. This kit has been configured for research use only."