FIGURE 6.

Stat3 overexpression reduces the sensitivity to GM-CSF stimulation in Shp2E76K-transduced cells. A, bone marrow low density mononuclear cells were isolated and co-transduced with WT Shp2 or Shp2E76K pMIEG3-EGFP in combination with pMIEG3-hCD4 or pMIEG3-Stat3CA-hCD4. Following transduction, cells were sorted for EGFP or human CD4 antigen expression using FACS to enrich for transduced double positive cells. B, Western blotting showing Shp2 and Stat3 overexpression in virus-transduced and FACS-enriched EGFP and CD4 expressing cells. C, methylcellulose-based colony forming assay demonstrating that Stat3CA expression corrects the gain-of-function Shp2-induced hematopoietic progenitor hypersensitivity to GM-CSF. Shown are representative data from two independent experiments that demonstrate similar results. GAPDH, glyceraldehyde-3-phosphate dehydrogenase. Error bars represent S.D.