FACS analysis of mobilized CD34⁺ enriched PBMC transduced with MFG-GC. Nontransduced (top panels) or MFG-GC transduced (bottom panels) CD34⁺ enriched PBMC were incubated at 37°C for 10 minutes in the absence (A) or presence (B) of 1 mmol/L CMFDGlu. Following substrate loading, FACS analysis was conducted as described for Gaucher fibroblasts. To approximate the fraction of GC positive cells in the transduced sample, logarithmic gating was applied to the substrate loaded samples. Fifty-thousand events were collected per sample. Results are displayed as 2% probability contour plots. Substrate loading did not decrease viability as measured by PI staining (data not shown).