BiKE- and TriKE-mediated NK cell targeting to tumor-associated antigens. (A) BiKEs or TriKEs are generated from the variable single-chain region of a specific monoclonal antibody containing the component capable of recognizing specific antigen. The anti-CD16 component recognizing NK cells can be combined with the single-chain component of 1 or 2 tumor-specific regions to create BiKE- or TriKE-targeted agents, respectively. (B) These drugs specifically enhance the immunologic synapse by specific recognition of tumor-associated antigens and delivery of a potent activating signal through CD16 on NK cells.