Calibrator 23 is a frozen blend of LAG3, Granzyme A, and Granzyme B. 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. LAG3 was expressed in a human cell line, Granzyme A and Granzyme B were expressed in a mouse cell line. Instructions on using Calibrator 23 are provided in U-PLEX Immuno-Oncology Group 1 Human Product Inserts.