Figure 6.

Working mechanisms of PD-1 and PD-L1 blockade in cancer therapy. Without treatment, PD-L1 expressed on tumor cells will be able to bind with PD-1 and activate the co-inhibitory signal to prevent the immune response. Using antibodies targeted against the receptor or its ligand, this interaction can be blocked in favor of immune activation. Adapted from “PD-1 Blocking Antibodies: Potential Repurposed Drug Candidate for COVID-19” by BioRender.com (2024). Retrieved from https://app.biorender.com/biorender-templates (accessed on 4 January 2024).