Skip to main content
. Author manuscript; available in PMC: 2011 May 11.
Published in final edited form as: Biochem Biophys Res Commun. 2002 Apr 26;293(1):463–469. doi: 10.1016/S0006-291X(02)00238-3

Figure 5. A differentiation-stage dependency of GM-CSF cell signaling model.

Figure 5

GM-CSF activates the Ras/MAPK and the PI3-K/p70S6K pathways in hematopoietic cells, but at different rates. In rapidly dividing cells (e.g., myeloid progenitors, leukemic cells) the former pathway is favored, while in mature cells (e.g., neutrophils) the latter pathway is more relevant. According to the data presented here, the MAPK pathway exerts a positive feedback on the p70S6K pathway, leading to an increased chemotaxis response in terminally differentiated cells. This molecular crosstalk becomes important in cells incapable of mitotic division (such as the neutrophil).