cross linking the agents attached to cell surface moieties on the t cells causing a signal to be transduced to the t cells 3 concentrating of the mixture by centrifugation 4 continued culture of the t cells at high cell density and 5 removal of media from the cultures at least daily and the dialysis of the media for retention of endogenous cytokines and replacement with fresh media and 6 repeat of the process as necessary with the same or different agents for labeling of the t cells in order to generate both the quantities of t cells necessary for infusion and the optimal function of the t cells for clinical effect the ability to design more efficient and effective t cell activation expansion and differentiation methods will be a direct result of the selection and timing of application of second materials second materials are agents which are capable of ligating t cell surface moieties and delivering a signal to the t cell upon cross linking these materials are preferably monoclonal antibodies or fractions or genetically manipulated versions thereof such as fusion proteins the selection of second materials will be as a result of understanding of the t cell activation expansion and differentiation process and the requirements for the type and duration of signals at any one time in the life of the responding t cells it is known that at least.