Studies on T-cell colony formation in chronic renal failure (CRF) patients

In order to study the possibility of abnormal differentiation and proliferation of T-cell precursors in chronic renal failure (CRF), we studied T-cell colony formation in CRF patients. The two-step monolayer method, with phytohemagglutinin-P as the inducer, was used for T-cell colony formation. In our results, colony formation was markedly reduced in CRF patients in comparison with normal controls, with about half of the former showing no colony growth. All cases showed a significant increase in colony numbers with in vitro plasmapheresis (the replacement of autologous plasma in the culture system with normal AB plasma). A significant increase in colony numbers was also seen with the addition of exogenous interleukin-2 (IL-2). The addition of IL-2 in the presence of normal plasma, in particular, induced an increase in colony numbers to near the levels in normal subjects. These results suggest that T-cell precursors exist in near normal numbers in CRF patients and that there are uremic inhibitors in the plasma. A reduced production of IL-2 is also indicated. These factors may be involved in the pathogenesis of immunodeficiency in CRF patients.