IL-2 effects on allogeneic and autologous transplant haemopoietic progenitors in long-term cultures

IL-2 therapy may be useful in situations with a low tumour burden, such as after autologous transplantation. However, conflicting reports about the deleterious effects of this cytokine on haemopoiesis have precluded its widespread use. To study IL-2 effects on haemopoietic transplant progenitors we established long-term cultures (Dexter-type) with cells from allogeneic marrow and marrow/peripheral blood cell infusates of autologous transplants with different concentrations of IL-2 (0-1000 IU/ml). Percentage of CD56+ cells was also determined in cultures. IL-2 induced an inhibitory effect on stroma and an increase in the percentage of CD56+ cells compared with controls. No deleterious effect either in the production of BFU-E or CFU-GM weekly or over the whole period of culture was observed. Our results suggest that IL-2 is able to induce an increase in CD56+ cells early after transplantation without a deleterious effect on long-term haemopoiesis.