Barbas and his team developed a two-stage chemical strategy that first puts the body’s antibodies on alert, and then gives them instructions on which targets to destroy. In the first stage, Barbas designed a chemical that, once injected, enables antibodies to form covalent bonds. Normally, antibodies cannot form such bonds. The second stage involves injecting a small adapter molecule with two parts: one that bonds covalently with antibodies, and the other that binds with a specific epitope, or cancer marker. When injected, this adapter molecule links with antibodies and then seeks out and attaches to a target’s specific epitope. The method is essentially like handing antibodies a beeper and putting them on standby. They wait around for a “call,” in the form of the adapter molecule, which, once connected, instantly leads them directly to a target’s weak spot, where the antibody can attack and deactivate the pathogen.