Binding of Sclerostin to the LRP5-Frizzled receptor contributes to osteoporosis as it blocks the interaction of Wnt with the receptor and thereby inhibits Wnt-driven bone remodeling. Therefore, inhibitors of Sclerostin are a target for treatment of osteoporosis. For screening inhibitors, Enzo® Life Sciences developed the chemiluminescent-based Leading Light™ Sclerostin-LRP Interaction Screening System. The LRP5-Sclerostin interaction can be manipulated by addition of the provided inhibitor Acid Green 25.
The assay performed on a CLARIOstar® microplate reader provides robust results as indicated by high Z' values. Furthermore, the LVF Monochromator™ allows for bandwidths up to 100 nm which correlate with a slight increase of the assay window. Addition of the Acid Green 25 inhibitor reduced the luminescent signal and allowed determination of its IC50 value.