Differences in GM-CSF production from mouse peripheral blood and spleen cells stimulated by different lectins

The capacity of mouse peripheral blood and spleen mononuclear cells to produce GM-CSF or CSA, in response to the stimulation by different mitogens (PHA, PWM and ConA) was studied. Each different kind conditioned medium was tested on target bone marrow from BALB/C mice. A significant decrease in the number of CFU-GM, was observed using peripheral blood conditioned medium stimulated by PHA or ConA in comparison with spleen conditioned medium in response to identical mitogens. When PWM is used as source of GM-CSF, significant differences between spleen and blood conditioned media were not observed. The possible significance of these findings is discussed.