Expression of cannabinoid receptors CB₂ in human BM HSPCs by flow cytometry. (A) Analysis of the surface expression of CB₂ in human BM MNCs and CD34⁺ cells isolated from human BM. This is a representative experiment of 5 experiments. (B) Analysis of CB₂ mRNA expression in BM MNCs compared with isolated CD34⁻, CD34⁺, CD133⁻, or CD133⁺ cells. RNA was isolated from the indicated populations of BM cells, and the expression of cannabinoid receptor mRNA was evaluated using the RT-PCR technique. GAPDH was used as an internal control. (C) Western blot analysis of CB₂ expression in CD34⁺ cells derived from human BM. Jurkat cell line was used as a positive control of CB₂ expression. (D) Analysis of surface expression of CB₂ in total peripheral blood MNCs and CD34⁺ cells isolated from G-CSF-mobilized peripheral blood. This is a representative experiment of 5 experiments. (E) Expression of CB2 in human CD34⁺CD38⁻ cells. A representative fluorescence-activated cell sorter profile of the CB₂ surface receptor expression in human BM CD34⁺CD38⁻ cells is shown.