Figure 4.

Illustration of aptamer involvement in cancer immunotherapy. (A) Two most crucial (most known) immune checkpoints. (B) Antagonistic aptamers, selected against either receptor or ligand, inhibit their interaction. Therefore, the downstream pathway is not triggered. Agonistic aptamers dimerize receptor dimers that result in switching on respective signaling. (C) Selected immune system receptors that have already been targeted by aptamers. (D) Whereas standard approaches use aptamers as targeting agents to deliver therapeutic cargo to cells, aptamer-engineered NK cells are directed by cell-membrane-embedded aptamers to lymphoma cells.