Cayman Chemical Bile Acid Nuclear Receptor FXR (NR1H4) Reporter Assay Kit

Cayman Chemical’s Bile Acid Nuclear Receptor FXR (NR1H4) Reporter Assay Kit is a cell-based assay for easy assessment of potential modulators of the bile acid receptor FXR. The kit consists of a 96-well plate coated with a transfection complex containing DNA constructs for expressing FXR and a BSEP promoter-regulated secreted alkaline phosphatase (SEAP) reporter.

Cells grown on the transfection complex will express FXRα2 inside the cells within 24 h from an engineered plasmid construct. To screen for agonists, antagonists or other modulators of the FXR nuclear receptors expressed on these cells, candidate compounds are added to the culture medium.

Agonist binding to FXR will trigger its transcription factor activity by activating the BSEP promoter on the reporter construct. This results in the expression of SEAP, which is secreted into the cell culture medium. Aliquots of media are collected 6–24 h after stimulation, and SEAP activity is measured following the addition of a luminescence-based alkaline phosphatase substrate.

Cayman’s reverse transfection reporter assays have overcome many of the disadvantages of other transfection approaches. Using solid-phase immobilised transfection, the uptake of the DNA complex by the cell is said to be increased compared to solution-phase transfection, enhancing both the transfection efficiency and co-transfection efficiency for multiple plasmids.

The system is suitable for rapid assay development and can be readily applied to high-throughput screening for therapeutic compounds regulating the activation of FXR.