A Unified Model of Immune Response II: Continuum Approach

In an earlier paper in this journal (1990, J. theor. Biol.145 , 207-215) we developed a unified model for normal immune response, autoimmune response and AIDS, where the concentration of each type of cell involved in the immune response is represented by a discrete automaton and the population dynamics of the relevant cells are formulated in terms of dynamical maps in discrete time. In this paper we study the continuum version of this unified model where the cell concentrations are represented by real variables whose evolution with continuous time is described by differential equations. We discuss possible ways to extend this model incorporating new experimental results and to generalize it along the new emerging trends in network theories of immune response. Our work also illustrates some of the relative advantages and disadvantages of the discrete and continuum formulations of the models of immune response.