GM-CSF secreted from TF-1 cells on CMo incubation activates STAT5.

(A) EMSA using the PRE probe and 8 μg WCE from TF-1 cells inoculated with CMo for 2, 6, and 24 hours in the absence (lanes 1-3) or in the presence (lanes 4-6) of neutralizing anti–GM-CSF antibodies. (B) GM-CSF production measured by ELISA in culture supernatants of TF-1 cells incubated for different times with CMo in the absence (gray bars) or in the presence (black bars) of neutralizing anti–GM-CSF antibodies. Exp indicates exposed.