A QUANTITATIVE MODEL SUGGESTS IMMUNE MEMORY INVOLVES THE COLOCALIZATION OF B-CELLS AND TH-CELLS

A prominent and essential feature of the humoral immune response of vertebrates is immunologic memory: the ability to recall previous exposure to antigen. We present a mathematical model of the growth and interactions of the major cell populations involved in the humoral immune response. Our analysis of this model predicts that the formation of a dynamic association between small numbers of antigen-specific B and Th cells, "colocalization', is sufficient to account for memory and the kinetics of the secondary response-neither specifically differentiated Th or B memory cells nor networks of antigen and anti-idiotypes are required. The colocalization hypothesis explains a number of existing experimental observations and can be tested by straightforward experiments which we describe. © 1991 Academic Press Limited.