IGEM:MIT/2005/Secondary/Primary antibody communication system
The second way we might build such a system is to introduce an additional level of modularity, in which there will be a secondary antibody fused to our cellular system, as in the first design, but in addition we will be able to swap in and out a primary antibody, that on the one end binds to our secondary antibody, and on the other end will bind to an antigen of choice. This system appears to be somewhat better for most in vitro applications, in which adding a primary antibody along with the antigen should not be an issue. It also should be applicable for systems that rely on feedback or intercellular signalling (see applications page). This system is not feasible, for example, for many environmental applications.