Human myeloid differentiation in the humanized CSF-1 mice. (A) Single-cell suspension of BM (top), spleen (middle), and peripheral blood (PB) from human CD34⁺ cells engrafted CSF1^m/m, CSF1^h/m, and CSF1^h/h mice were prepared, stained with CD45, CD14, and CD33 human antibodies, and analyzed by flow cytometry. Cells that are human CD45⁺ were pregated and discriminated based on CD14 and CD33 expression. (B-C) Percentages (B) and absolute numbers (C) of human CD45⁺ CD14⁺CD33⁺ cells of BM (top), spleen (middle), and peripheral blood (PB) were calculated. Absolute numbers of BM cells were determined as average per animal (2 tibia and fibula) and of peripheral blood were determined per milliliter volume of blood. Each group contains n = 20 mice. Each symbol represents an individual mouse; horizontal bars indicate the mean values. Data are representative of 5 independent experiments.