Immune checkpoints serve a critical role in the immune system to prevent autoimmunity and manage the degree and duration of an immune response. Cytotoxic T-Lymphocyte-associated protein 4 (CTLA-4 or CD152) is an inhibitory transmembrane protein involved in an immune checkpoint of significant interest for therapeutic development. When CTLA-4 is expressed and competes with CD28, the immune system response is downregulated. As a result of this immune system response balance, immune checkpoints provide an opportunity for therapeutic intervention to modulate immune system activity.
There is a high demand for new drugs to block CTLA-4 and modulate immune system activity. In this application note, we demonstrate how to screen for novel CTLA-4 blocking drugs by utilizing the AlphaLISA CTLA-4/CD80 binding assay.