THUNDER® Human CCL17 assay helps Pfizer scientists advance their drug discovery research

BioAuxilium products continue to support cutting-edge drug discovery research. Recently, scientists from Pfizer have published patent WO2025133961 describing novel signal transducer and activator of transcription 6 (STAT6) inhibitors. STAT6 is a transcription factor that selectively mediates signaling from IL-4 and IL-13, two cytokines that are central to type 2 inflammation. STAT6 activation is essential for the expression and secretion of CCL17/TARC (Thymus and Activation-Regulated Chemokine) in many immune and epithelial cells. To characterize the potency (IC50) of test compounds for the inhibition of CCL17/TARC secretion in peripheral human whole blood (HWB), the investigators used the first-to-market THUNDER® Human CCL17/TARC TR-FRET Biomarker Assay Kit.

Briefly, the high-throughput HWB assay protocol included the following key steps:

• nanoliter spotting of test compounds into a 384-well v-bottom polypropylene microplate
• addition of human whole blood and incubation with the test compounds for two hours at 37^oC
• addition of IL-13 to stimulate CCL17 production
• incubation of the plate at 37^oC for 48 hours
• centrifugation of the plate to obtain serum
• transfer of serum to a 384-well white low volume non-binding microplate containing the THUNDER CCL17/TARC antibody mix
• centrifugation of the microplate
• sealing of the plate and incubation for 16 hours at room temperature
• reading of the TR-FRET signals at both 665 and 615 nm

The patent reports that several compounds reduced IL-13-induced CCL17 secretion in HWB with nanomolar potency.

A big thank you to the Pfizer scientists who continue to trust our THUNDER TR-FRET assay kits. These discoveries inspire us to keep developing high-quality, reproducible TR-FRET tools that advance biomedical research.