(T1230-06-37) Expansion of the Human Immuno-Oncology Assay Portfolio on a Multiplexed Electrochemiluminescence Platform

Purpose: Novel developments in immuno-oncology research have driven an increased demand for the sensitive measurements of biomarkers associated with cancer, immune responses, and targets of therapeutic drugs. The levels of these biomarkers are frequently altered in samples from cancer patients and can be evaluated by measuring their concentrations in blood and tissue lysate samples. We had previously developed and launched 27 immuno-oncology assays targeting both traditional and emergent cancer biomarkers. We now report expansion of this group with the introduction of 24 additional assays. The assays are available on the U-PLEX platform and can be multiplexed with 80 other U-PLEX assays. The combined group of 131 assays allows for flexible and simultaneous measurements of immuno-oncology, inflammation, and metabolic analytes.

Methods: Unbiased, pairwise antibody screening for immuno-oncology targets was performed on U-PLEX plates using biotinylated capture antibodies and SULFO-TAG labeled detection antibodies. Optimal antibody pairs were identified using assay performance parameters such as dynamic range, sensitivity, specificity, sample recognition, and matrix tolerance. Spike recovery, dilution linearity, and sample recognition were evaluated in tissue lysates, serum, and plasma. The precision and accuracy of each assay were determined from at least 17 experimental runs using assay-specific controls. Singleplex and multiplex assay performance were well correlated for all analytes.

Results: Twenty-four new assays were developed to measure human immuno-oncology targets. The assays demonstrated 3-4 logs of dynamic range and low to sub-pg/mL lower limits of detection (LLOD) for most. Control samples for each assay showed expected precision and accuracy, with intra-run %CVs less than 10%, inter-run %CVs less than 25%, and recoveries largely within 80-120% of target concentrations. Dilution linearity and spike recovery studies demonstrated matrix tolerance and accurate measurement across the matrices tested, with recoveries typically between 80-120%. All assays were able to measure the target analyte in most matrices tested.

Conclusion: The U-PLEX immuno-oncology assay portfolio has expanded to 51 assays with the addition of 24 human assays. U-PLEX assays allow sensitive and reliable measurement of traditional and emergent biomarkers associated with cancer and cancer immunotherapies. They can be run in singleplex and multiplex formats and include many important immuno-oncology analytes including CTLA-4, BCMA, MIG, Perforin, Granzyme A, and Granzyme B. Markers of angiogenesis and cancer metastasis such as VEGFR-1, proMMP-9, and MMP-9 (total) have been added to the immuno-oncology group. In addition, there are therapeutic antibody-sensitive and -insensitive assays that target different epitopes on PD-1 and PD-L1. Moreover, these assays can be run in combination with 80 other U-PLEX assays, enabling researchers and drug developers to simultaneously measure immuno-oncology, cytokine, chemokine, and metabolic biomarkers.