Some representative examples of flow cytometric measurements of Notch receptors expression by both B-ALL cells and hBM-MSCs. Representative cases of the expression of Notch receptors by both B-ALL cells and hBM-MSCs cultured alone and cocultured for 3 and 7 days, after electronic gating either on CD19⁺ B-ALL cells or CD45⁻ hBM-MSCs in 2-color flow cytometric analysis. Filled histograms indicate the staining with control human IgG.