Optimization and utilization of the SureFire phospho-STAT5 assay for a cell-based screening campaign

Area of Science:

• Cellular signaling and molecular biology
• Biochemistry and immunology

Background:

• Signal transducers and activators of transcription (STATs) are key transcription factors activated by tyrosine phosphorylation, primarily mediated by Janus kinases (JAKs).
• The JAK/STAT pathway is crucial for hematopoietic and immune cell function, with STAT5 playing essential roles in T cell development and its dysregulation linked to hematologic malignancies.

Purpose of the Study:

• To evaluate the utility of the SureFire pSTAT5 assay, based on AlphaScreen technology, for detecting STAT5 phosphorylation.
• To assess the suitability of this assay for high-throughput screening (HTS) applications in drug discovery.

Main Methods:

• Utilized the homogeneous SureFire pSTAT5 assay with AlphaScreen technology to detect phosphorylated STAT5 in cell lysates.
• Evaluated erythropoietin (EPO)-induced STAT5 phosphorylation in HEL cells.
• Conducted a small-scale screening campaign to identify inhibitors of EPO-induced STAT5 phosphorylation.

Main Results:

• The SureFire pSTAT5 assay successfully detected EPO-induced STAT5 phosphorylation in HEL cells.
• The assay demonstrated robustness and reliability in a small-scale screening campaign.
• The assay format proved amenable to high-throughput screening (HTS) applications.

Conclusions:

• The SureFire pSTAT5 assay is a reliable and robust method for detecting phosphorylated STAT5.
• This assay is well-suited for high-throughput screening (HTS) to identify modulators of the JAK/STAT pathway, particularly STAT5 phosphorylation.