Figure I.

Scheme of the Communication Channel between an Input (Sender) and an Output (Receiver). A communication channel can be visualized as a ‘box’ through which information is transmitted. For example, in intracellular communication, the channel may be the JAK/STAT signaling pathway, or, for intercellular communication, one cell may be a sender and another the receiver. Information theory allows quantification and analysis of communication systems such as these found between and within cells in the functional – and dysfunctional – immune system.