Communication between cells is a crucial part of the immune response. The importance of cytokines and immunological synapses for this purpose has long been recognized. Connexin-based gap junctions that allow exchange of molecules between adjacent cells also seem to have an important role. Recent work suggests that gap junction-mediated antigen transport might be a mechanism of immune-response regulation. Here, we discuss this idea in more detail and suggest possible ways in which this mechanism might have both positive and negative impacts during an immune response.