Self-nonself discrimination due to immunological nonlinearities: the analysis of a series of models by numerical methods

Abstract

In a set of models incorporating a varying amount of immunological complexity, we investigate processes by which T lymphocytes 'learn' to discriminate self from nonself. The models all incorporate the following immunological data: (1) T lymphocytes produce their own growth factor (IL2), (2) T lymphocyte effectors proliferate in response to IL2 and antigen. and (3) T lymphocyte effectors become memory cells whenever antigenic restimulation is poor. The first two facts are sufficient to generate a proliferation treshold; the (self-reinforcing) proliferation process only starts when IL2 concentrations are sufficiently high.