High Fidelity Detection of Endogenous PD-L1 at Low Picogram Levels with Simple Plex Assays

Enlisting a patient's own immune system to fight cancer has been a longstanding dream for cancer biologists. Immune checkpoint inhibitors targeting molecules like programmed death-ligand 1 (PD-L1) help make the dream a reality and are now transforming today's cancer therapy. PD-L1 therapy has gained interest as a paradigm shifting approach to cancer treatment due to its durable effects, and its ability to target a broad range of cancers with manageable toxicity compared to traditional chemotherapy.

Current diagnostic tests for PD-L1 use immunohistochemistry (IHC) to score the tumor microenvironment, but results can be really variable. And traditional, high-quality ELISAs don't always have the sensitivity to detect endogenous levels of PD-L1 in primary patient samples. Ella's Simple Plex™ PD-L1 assay gets rid of these downsides, letting you detect single-digit picogram levels of endogenous PD-L1 with single-digit CVs. Reproducibility at that level means you can have confidence in your data. Plus, you'll only need 25 µL of neat sample and your results are ready in an hour. For these reasons, researchers at the NIH recently used all the advantages of Simple Plex assays to monitor immunotherapy responses in humans.

Simple Plex assays also give you single plex and multiplex options so you can measure levels of just PD-L1 alone or PD-L1 in a panel with three other proteins in your sample.

In this application note, we compare endogenous PD-L1 detection in PTEN mutated glioma cell supernatant and blood cells using the Simple Plex assay and a commercially available sandwich ELISA assay to demonstrate data equivalency and the added sensitivity you'll get with a Simple Plex assay.