A model of T cell-target interaction leading to lymphokine release

Binding of antigenic cells by activated T lymphocytes can trigger the release of a number of soluble factors, including the lymphokine interleukin 3 (IL3). The cellular interaction between T cells and allogeneic cells which are involved in the triggering of lymphokine release from T cells are still poorly understood. We have examined the relationship between antigenic cell number, T cell number and IL3 release and have derived a steady state binding model which adequately accounts for the experimental data if it is assumed that triggering is an all or none phenomenon. We find that binding of at least two antigenic cells by an allo-reactive T cell is necessary to trigger lymphokine release.