CBMCs cocultured with 3T3 fibroblasts increased their expression of G_i3α protein.

(A) SDS-PAGE immunoblot was performed with lysates of CBMCs maintained in suspension or cocultured with 3T3 fibroblasts for 4 days in the presence of soluble SCF (100 ng/mL). G_i3α purified from bacterial lysates was used as positive control. Confocal microscopy images of G_i3α protein under orange fluorescence (FITC) showing: (B) membrane localization in CBMCs maintained in coculture with 3T3 fibroblasts for 4 days in the presence of SCF (100 ng/mL), (C) no expression in CBMCs maintained in suspension for 4 days in the presence of SCF (100 ng/mL), and (D) perinuclear localization in freshly isolated rat peritoneal mast cells. The displayed figures are from a representative single experiment of 3. Arrows indicate G_i3α expression with the mast cells. Original magnification B-D, × 63.