New Transcreener CD73 Assay for Discovery of Therapeutics to Enhance Tumor Immunity

Researchers at BellBrook Labs have developed a high throughput screening (HTS) assay to discover small molecule modulators for the immunosuppressive ectonucleotidase, CD73.  The Transcreener ADO CD73 Assay detects adenosine (ADO), the product of a CD73 reaction, allowing researchers to monitor CD73 activity with simple, mix-and-read fluorescent detection.

Also known as ecto-5’ nucleotidase or 5’-nucleotidase, CD73 is an anchored cell surface protein that plays a critical role in purinergic signaling by catalyzing the hydrolysis of AMP into adenosine and phosphate. Multiple lines of research have shown that adenosine is immunosuppressive in the tumor microenvironment, and ectonucleotidase enzymes have emerged as promising immuno-oncology targets.

The Transcreener CD73 Assay is a competitive immunoassay that uses a coupling enzyme to convert AMP to ADP, which is then detected by the proven Transcreener ADP² Assay.  The assay is designed for HTS in miniaturized 384 or 1536 well formats.  It provides a quantitative measurement of CD73 enzyme velocity and thus has excellent utility for all aspects of screening and hit-to-lead, including dose-response measurements and mechanistic studies, as well as basic research on CD73 enzymology and regulation.

Targeting the CD73 pathway, in combination with other potentially complementary immune pathways, is a potential strategy to help activate an anti-tumor immune response. The availability of HTS-compatible Transcreener assay methods from BellBrook Labs is intended to help accelerate the discovery of inhibitors for enzymes such as CD73, which play a role in tumor immunity and other diseases impacted by adenosine signaling.