Considerable work needs to be done in order to understand the immunosuppressive effect of 'uremia' and the lymphocyte changes induced by hemodialysis. For example, the lymphocyte population dynamics can be further defined using monoclonal antibodies specific for lymphocyte subgroups. In vitro assays are available for lymphokine detection (i.e. IL-1, IL-2 which are important for T cell function) and may be correlated with both the clinical state and overall immunobiological status of hemodialyzed patients. The possibility of specifically delineating the extent of the immune system dysfunction in renal failure patients (on or off dialysis) is at hand. With this knowledge it will be possible to manipulate their management so as to minimize function alterations.