Abstract

There are several new emerging modalities within drug discovery that require new types of assays for screening and mechanistical studies. Two examples that expands rapidly are PROTACs and ASOs, both targeting the level of the protein of interest through different mode of action. To meet the demands of protein detection assays we have used the AlphaLISA technology in several projects. The assay is a homogenous, proximity assay. This approach does not require cell line engineering and can be applied on a wide range of cell types provided that the endogenous expression level is sufficient. The assay development is relatively quick and by using design of experiment (DoE) the identification of an antibody pair and defining the optimal assay conditions can be done in as few as three experiments.

We have established AlphaLISA assays in both adherent and suspension cells and for a range of different target classes. In many of the assays we have used anti-species AlphaLISA beads, but we have also used biotinylated antibodies together with streptavidin beads or direct conjugation of antibodies to the beads. As with any type of assay the AlphaLISA relies on high quality reagents, in this case antibodies, and the challenge of the assay build can be the quality or the limitation of the available antibodies. Apart from screening and characterization, the final assay can be used to translate results between different cell lines and for analysis of in vivo samples.