A network theory of the immune system.

The fact that every antibody also has antigenic properties leads to the existence of a functional network of interacting antibodies and lymphocytes in the immune system. With a minimum set of assumptions about the nature of these interactions some of the principal features of the immune response such as normal primary and secondary response, low and high zone tolerance induction, and memory can be reproduced. The low zone tolerance phenomenon plays a central role in our theory, as it is the simplest nontrivial mode of response to an antigenic stimulus. It may be understood as the defeat of the stimulated lymphocyte species against their internal adversaries. The normal response and high zone tolerance induction may be characterized as low zone tolerance on a second and third level of a hierarchy of lymphocyte populations. In particular, the weakness of the primary response is explained in terms of internal struggles which lead to a final suppression of the aggressors, thereby opening the way for an unhindered secondary response.