Calibrator 27 is a lyophilized blend of APRIL/TNFSF13, E-Selectin, Galectin-9, HVEM/TNFRSF14, MIG, Pentraxin 3, and RAGE (soluble). It is intended for use as an assay calibrator for MSD U-PLEX human assays that measure any of the included proteins. The utility of this product has not been evaluated in other applications. Individual analyte concentrations are provided in the lot-specific certificates of analysis. E-Selectin and Pentraxin 3 were expressed in hamster cells; APRIL/TNFSF13, Galectin-9, HVEM/TNFRSF14, MIG, and RAGE (soluble) were expressed in a human cell line. Instructions on using Calibrator 27 are provided in U-PLEX Immuno-Oncology Group 1 Human Product Inserts.