as antiapoptotic agents by competing with the trimers for binding to the death receptors the present invention discloses how to generate death ligands consisting of stable tetramers and deliver these ligands either as purified proteins or exposed on the surface of apcs to induce apoptosis in lymphocytes expressing the counter death receptors we hypothesize that death ligands are more effective in inducing apoptosis when in trimers or higher order of structures based upon the available data from similar biological systems the preferred embodiment for the formation of tetramers and higher order of structures is streptavidin or avidin both of which form tetramers and higher structure under physiological conditions a modified form of streptavidin has been chosen as the preferred molecule in this patent application and is referred to as csa throughout this document apoptosis of activated t cells results in tolerance to allografts and xenografis including bone marrow and other organ transplantation purging of activated t cells also relieves the symptoms of allergies and other immune induced diseases included in the latter are autoimmune disorders such as multiple sclerosis lupus erythematosus sarcoidosis diabetes and rheumatoid arthritis many disorders including some tumors are dependent on lymphocyte functions that lead to persistence of the disorder many hematological disorders could be treated with bone marrow stem cell transplants if the immune response could be regulated so as to induce tolerance to the foreign stem cells among these disorders are leukemias lymphomas aplastic anemia sickle cell and cooley 39 s anemia and the like all.